COGENERATION CORP OF AMERICA
SC 13D, 1999-09-07
COGENERATION SERVICES & SMALL POWER PRODUCERS
Previous: ADDISON CAPITAL SHARES INC, N-30D, 1999-09-07
Next: KAUFMAN & BROAD HOME CORP, 4/A, 1999-09-07



<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549


                                  SCHEDULE 13D
                                 (Rule 13d-101)

             Information to be included in statements filed pursuant
            to Rule 13d-1(a) and amendments thereto filed pursuant to
                                  Rule 13d-2(a)

                       COGENERATION CORPORATION OF AMERICA
                                (Name of Issuer)

                     COMMON STOCK, PAR VALUE $.01 PER SHARE
                         (Title of Class of Securities)

                                   628950 10 7
                                 (CUSIP Number)

                                  Ann B. Curtis
                               Calpine Corporation
                           50 West San Fernando Street
                               San Jose, CA 95113
                                 (408) 995-5115
            (Name, Address and Telephone Number of Person Authorized
                     to Receive Notices and Communications)

                                 With a copy to:

                            William R. Collins, Esq.
                            Howard, Smith & Levin LLP
                           1330 Avenue of the Americas
                               New York, NY 10019
                                 (212) 841-1000

                                 August 26, 1999
             (Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition which is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box
[ ].



<PAGE>   2
                                  SCHEDULE 13D


CUSIP No.   628950 10 7


1)                 Name of Reporting Persons:  Calpine Corporation
                   I.R.S. Identification Nos. of Above Person:  77-0498817

2)                 Check the Appropriate Box if a Member of a Group.
                   [  ]  (a)
                   [  ]  (b)

3)                 SEC Use Only

4)                 Source of Funds.  AF, WC, BK

5)                 [  ]  Check if Disclosure of Legal Proceedings is Required
                   pursuant to Items 2(d) or 2(e).

6)                 Citizenship or Place of Organization.
                   Delaware

Number of Shares   7)         sole voting power           0
beneficially
owned by each      8)         shared voting power         3,106,612
reporting person
with               9)         sole dispositive power      0

                   10)        shared dispositive power    3,106,612

11)                Aggregate amount beneficially owned by each reporting person
                   3,106,612

12)                [  ]  Check if the Aggregate Amount in Row (11) Excludes
                   Certain Shares.

13)                Percent of Class Represented by Amount in Row (11).
                   45.30%

14)                Type of Reporting Person.
                   CO



                                      -2-
<PAGE>   3

                                  SCHEDULE 13D


CUSIP No.  628950 10 7


1)                 Name of Reporting Persons:  Calpine East Acquisition Corp.
                   I.R.S. Identification Nos. of Above Person:  77-0520358

2)                 Check the Appropriate Box if a Member of a Group.
                   [  ]  (a)
                   [  ]  (b)

3)                 SEC Use Only

4)                 Source of Funds.  AF, WC

5)                 [  ]  Check if Disclosure of Legal Proceedings is Required
                   pursuant to Items 2(d) or 2(e).

6)                 Citizenship or Place of Organization.
                   Delaware

Number of Shares   7)       sole voting power           0
beneficially
owned by each      8)       shared voting power         3,106,612
reporting person
with               9)       sole dispositive power      0

                   10)      shared dispositive power    3,106,612

11)                Aggregate amount beneficially owned by each reporting person
                   3,106,612

12)                [  ]  Check if the Aggregate Amount in Row (11) Excludes
                   Certain Shares.

13)                Percent of Class Represented by Amount in Row (11).
                   45.30%

14)                Type of Reporting Person.
                   CO





                                      -3-
<PAGE>   4
ITEM 1.  SECURITY AND ISSUER.

                  This Statement on Schedule 13D (the "Statement") relates to
the common stock, par value $.01 per share (the "Common Stock"), of Cogeneration
Corporation of America (the "Company"). The principal executive offices of the
Issuer are located at One Carlson Parkway, Suite 240, Minneapolis, Minnesota
55447.

ITEM 2.  IDENTITY AND BACKGROUND.

                  (a)-(c) and (f) This Statement is filed by Calpine East
Acquisition Corp., a Delaware corporation ("Merger Subsidiary"), and Calpine
Corporation, a Delaware corporation ("Calpine"). Merger Subsidiary, a
wholly-owned subsidiary of Calpine, was organized to acquire the Company and has
not conducted any unrelated activities since its organization on August 23,
1999. Calpine is a leading independent power company engaged in the development,
acquisition, ownership and operation of power generation facilities and the sale
of electricity predominantly in the United States. The principal executive
offices of Calpine and Merger Subsidiary are located at 50 West San Fernando
Street, San Jose, California 95113. The name, age, business address, present
principal occupation or employment, five-year employment history and citizenship
of each director and executive officer of Merger Subsidiary and Calpine are set
forth in Schedule I hereto.

                  (d) and (e) None of Merger Subsidiary, Calpine or, to the best
knowledge of such corporations, any of the persons listed on Schedule I, has
during the last five years (i) been convicted in a criminal proceeding
(excluding traffic violations or similar misdemeanors) or (ii) been a party to a
civil proceeding of a judicial or administrative body of competent jurisdiction
and as a result of such proceeding was or is subject to a judgment, decree or
final order enjoining future violations of, or prohibiting activities subject
to, Federal or state securities laws or finding any violation of such laws.

ITEM 3.  SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.

                  The total amount of funds required by Merger Subsidiary to
consummate the Merger (as defined below) (including refinancing, if necessary,
certain indebtedness of the Company and its subsidiaries, and paying related
fees and expenses) is expected to be approximately $233 million. Merger
Subsidiary will obtain all funds needed for the Merger from Calpine by means of
a capital contribution, loan or a combination thereof. Calpine will obtain such
funds (i) from its general corporate funds and/or (ii) by borrowing under its
existing Credit Agreement, dated as of September 25, 1996, as amended as of May
15, 1998 (as amended, the "Credit Agreement"), among Calpine, as borrower, the
banks and other financial institutions party thereto, as lenders, and the Bank
of Nova Scotia, as agent. The Credit Agreement provides for borrowings of up to
an aggregate of $100,000,000 of loans on an unsecured basis. Borrowings under
the Credit Agreement bear interest at the Bank of Nova Scotia's base rate plus
an applicable margin or at LIBOR plus an applicable margin. The Credit Agreement
includes customary covenants including financial covenants.

                                      -4-
<PAGE>   5
                  As of August 30, 1999, Calpine had (i) cash-on-hand (including
cash equivalents and marketable securities) of approximately $250 million and
(ii) availability to borrow up to an additional $79 million of loans under the
Credit Agreement.

                  The foregoing summary of the source and amount of funds is
qualified in its entirety by reference to the text of the Credit Agreement, a
copy of which is filed as an exhibit to Calpine's Current Report on Form 8-K,
dated May 1, 1996, filed with the Securities and Exchange Commission and is
incorporated in this Statement by reference.

                  Although no definitive plan or arrangement for repayment of
borrowings under the Credit Agreement have been made, Calpine anticipates such
borrowings will be repaid with internally generated funds (including, if the
Merger is accomplished, those of the Company) and from other sources which may
include the proceeds of future bank refinancings or the public or private sale
of debt or equity securities. No decision has been made concerning the method
Calpine will use to repay the borrowings under the Credit Agreement. Such
decision will be made based on Calpine's review from time to time of the
advisability of particular actions, as well as prevailing interest rates,
financial and other economic conditions and such other factors as Calpine may
deem appropriate.

ITEM 4.  PURPOSE OF TRANSACTION.

                  On August 26, 1999, Calpine and Merger Subsidiary entered into
an Agreement and Plan of Merger (the "Merger Agreement") with the Company which
provides that, subject to the terms and conditions thereof, Merger Subsidiary
will merge with and into the Company with the Company continuing as the
surviving corporation (the "Merger"). Upon consummation of the Merger, all
outstanding shares of Common Stock (other than shares held by Calpine or Merger
Subsidiary) will be converted into the right to receive $25.00 per share in
cash.

                  Concurrently with the execution of the Merger Agreement,
Calpine, Merger Subsidiary and NRG Energy, Inc., a Delaware corporation ("NRG"),
have entered into a Contribution and Stockholders Agreement, dated as of August
26, 1999 (the "Stockholders Agreement"). The Stockholders Agreement provides
that, subject to the terms and conditions thereof, immediately prior to the
consummation of the Merger (i) NRG will contribute to Merger Subsidiary a number
of shares of Common Stock equal in value to (A) at least 20% of the total equity
value of the Company less (B) the value of certain stock options held by NRG
employees which are currently directors of the Company which have been or will
be cancelled prior to the Merger, for 20% of the ownership interest in Merger
Subsidiary and (ii) Calpine will contribute to Merger Subsidiary sufficient cash
equal to 80% of the total equity value of the Company. Upon consummation of the
Merger, NRG will own 20% and Calpine will own 80% of the outstanding shares of
Common Stock of the Company. The total equity value of the Company is defined as
the sum of (i) the total number of outstanding shares of Common Stock multiplied
by $25.00 (the "Merger Price") and (ii) the aggregate amount of the excess of
the Merger Price over the exercise price of each of the outstanding stock
options of the Company which are currently exercisable or will become
exercisable upon consummation of the Merger. Calpine has also agreed to
contribute cash, in the form of a loan, sufficient to satisfy certain

                                      -5-
<PAGE>   6
obligations of the Company.

                  The Stockholders Agreement provides that the Board of
Directors of the Company following the Merger shall consist of no more than
seven directors with one director being appointed by NRG. In addition, the
consent of NRG is required for the Company or its subsidiaries to take certain
actions including, without limitation, actions relating to (i) the issuance of
securities, (ii) the sale or disposition of subsidiaries or assets, (iii)
amendments to its certificate of incorporation or by-laws, (iv) mergers or
consolidations with third parties and (v) certain agreements with affiliates.
The Stockholders Agreement prohibits Calpine and NRG from transferring their
respective shares of Common Stock of the Company following the Merger for a
period of three years without the prior written consent of the other
stockholder, which consent cannot be unreasonably withheld or delayed.

                  In addition, pursuant to the Stockholders Agreement, NRG has
granted Calpine an irrevocable proxy with respect to all of the shares of Common
Stock held by it (constituting 45.3% of the outstanding shares) to vote such
shares in favor of approval of the Merger Agreement at a duly convened meeting
of the Company's stockholders for such purpose. In the Merger Agreement, the
Company has represented that the affirmative vote of the holders of two-thirds
of the outstanding shares of the Company's Common Stock is required to approve
the Merger.

                  The Stockholders Agreement provides that following the Merger
Calpine shall have the right to acquire NRG's 20% interest in the Company during
the 365-day period commencing on the third anniversary of the closing of the
Merger for the fair market value of the interest as determined by an independent
investment bank. In addition, at the closing of the Merger, certain existing
operating and management and service agreements between NRG and its affiliates,
on the one hand, and the Company and its affiliates, on the other hand, will be
terminated at the effective time of the Merger and will be replaced by
agreements between the Company and Calpine.

                  The foregoing summary of the Stockholders Agreement is
qualified in its entirety by reference to the Stockholders Agreement which is
attached hereto as Exhibit 3. There can be no assurances that there will be any
transaction resulting from the foregoing.

ITEM 5.  INTEREST IN SECURITIES OF THE ISSUER.

                  As a result of entering into the Stockholders Agreement,
Calpine and Merger Subsidiary beneficially own 3,106,612 shares of Common Stock
which represents 45.3% of the outstanding shares of Common Stock. See Item 4 of
this Statement for a description of the Stockholders Agreement. Except as
described in this Statement, neither Calpine, Merger Subsidiary nor, to their
knowledge, any of the persons listed in Schedule I or any associate or
majority-owned subsidiary of any of the foregoing, beneficially owns or has the
right to acquire any equity securities of the Company, nor has Calpine, Merger
Subsidiary or, to their knowledge, any of the persons or entities referred to
above or any of the respective executive officers, directors or subsidiaries of
any of the foregoing, effected any transaction in the equity securities

                                      -6-
<PAGE>   7
of the Company during the past 60 days.

ITEM 6.  CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT
             TO SECURITIES OF THE ISSUER.


                  See Item 4 for a description of the Stockholders Agreement
among Calpine, Merger Subsidiary and NRG. Except as described in this Statement,
neither Calpine, Merger Subsidiary nor, to their knowledge, any of the persons
listed in Schedule I, has any contract, arrangement, understanding or
relationship with any other person with respect to any securities of the
Company, including, but not limited to, any contract, arrangement, understanding
or relationship concerning the transfer or the voting of any securities of the
Company, joint ventures, loan or option arrangements, puts or calls, guaranties
of loans, guaranties against loss or the giving or withholding of proxies.

ITEM 7.  MATERIAL TO BE FILED AS EXHIBITS.


(1)      Joint Filing Agreement, dated September 7, 1999, between Calpine and
         Merger Subsidiary.

(2)      Agreement and Plan of Merger, dated as of August 26, 1999, among the
         Company, Calpine and Merger Subsidiary.

(3)      Contribution and Stockholders Agreement, dated as of August 26, 1999,
         among Calpine, Merger Subsidiary and NRG.

(4)      Confidentiality Agreement, dated May 17, 1999, between Calpine and the
         Company.

(5)      Credit Agreement, dated September 25, 1996, among Calpine and the Bank
         of Nova Scotia (previously filed as an exhibit to Calpine's Current
         Report on Form 8-K dated May 1, 1996 and incorporated herein by
         reference).



                                      -7-
<PAGE>   8
                                    SIGNATURE

                  After reasonable inquiry and to the best of my knowledge and
belief, the undersigned certifies that the information set forth in this
statement is true, complete and correct.

Dated:  September 7, 1999



                       CALPINE EAST ACQUISITION CORP.


                       By: /s/  Ann B. Curtis
                                -------------
                           Name:     Ann B. Curtis
                           Title:    Vice President, Chief Financial Officer and
                                     Secretary


                       CALPINE CORPORATION


                       By: /s/  Ann B. Curtis
                                -------------
                           Name:     Ann B. Curtis
                           Title:    Executive Vice President







                                      -8-
<PAGE>   9
                                  EXHIBIT INDEX

(1)      Joint Filing Agreement, dated September 7, 1999, between Calpine and
         Merger Subsidiary.

(2)      Agreement and Plan of Merger, dated as of August 26, 1999, among the
         Company, Calpine and Merger Subsidiary.

(3)      Contribution and Stockholders Agreement, dated as of August 26, 1999,
         among Calpine, Merger Subsidiary and NRG.

(4)      Confidentiality Agreement, dated May 17, 1999, between Calpine and the
         Company.

(5)      Credit Agreement, dated September 25, 1996, among Calpine and the Bank
         of Nova Scotia (previously filed as an exhibit to Calpine's Current
         Report on Form 8-K dated May 1, 1996 and incorporated herein by
         reference).





                                      -9-
<PAGE>   10
                                                                      SCHEDULE I

               INFORMATION CONCERNING THE DIRECTORS AND EXECUTIVE
                    OFFICERS OF CALPINE AND MERGER SUBSIDIARY




1. DIRECTORS AND EXECUTIVE OFFICERS OF CALPINE. The following table sets forth
the name, age, business address and present principal occupation or employment,
and material occupations, positions, offices or employment for the past five
years of each director and executive officer of Calpine. Each such person is a
citizen of the United States of America. Unless otherwise indicated below, the
business address of each person is c/o Calpine Corporation, 50 West San Fernando
Street, San Jose, California, 95113. Unless otherwise indicated, each occupation
set forth opposite an individual's name refers to employment with Calpine.

<TABLE>
<CAPTION>
                                                                        Present Principal Occupation
              Name and                                                or Employment; Material Positions
          Business Address               Age                            Held During Past Five Years
          ----------------               ---                            ---------------------------
<S>                                      <C>             <C>
Peter Cartwright.....................    69              Director  of  Calpine  since  1984,  Chairman  of the Board
                                                         since  September   1996,   President  and  Chief  Executive
                                                         Officer since 1984.

Ann B. Curtis........................    48              Director  of Calpine  since  September  1996 and  Executive
                                                         Vice  President  since August  1998.  From  September  1992
                                                         until August 1998, Ms. Curtis was Senior Vice President.

Jeffrey E. Garten....................    52              Director of Calpine since  January  1997.  Dean of the Yale
Dean, School of Management                               School of Management  and William S. Beinecke  Professor in
Yale University                                          the  Practice  of  International  Trade and  Finance  since
Box 208200                                               November  1995.  From November  1993 to October  1995,  Mr.
New Haven, CT 06520-8200                                 Garten   served   as    Undersecretary   of   Commerce   of
                                                         International Trade.

Susan C. Schwab......................    44              Director  of  Calpine  since  January  1997.  Dean  of  the
Dean, School of Public Affairs                           School of Public  Affairs  at the  University  of  Maryland
University of Maryland                                   since  August  1995.  From July 1993 to  August  1995,  Dr.
Room 2101 Van Munching Hall                              Schwab served as Director,  Corporate Business  Development
College Park, MD 20742                                   at Motorola, Inc.
</TABLE>

                                      I-1
<PAGE>   11

<TABLE>
<S>                                      <C>             <C>
George J. Stathakis..................    68              Director  of  Calpine  since   September  1996  and  Senior
                                                         Advisor  since  December  1994.  Mr.   Stathakis  has  been
                                                         providing  financial,   business  and  management  advisory
                                                         services to numerous  corporations since 1985.  Chairman of
                                                         the  Board  and  Chief   Executive   Officer   of   Ramtron
                                                         International   Corporation,    an   advanced   technology
                                                         semiconductor company, from 1990 to 1994.

John O. Wilson.......................    60              Director of Calpine  since January  1997.  Senior  Research
Senior Research Fellow                                   Fellow,  Berkeley  Roundtable on the International  Economy
Berkeley Roundtable on the                               and  Executive  Vice  President  and Chief  Economist,  SDR
    International Economy (BRIE)                         Capital  Management,  Inc.  since January 1999.  Mr. Wilson
2234 Piedmont Avenue                                     served as Executive Vice  President and Chief  Economist at
University of California, Berkeley                       Bank of America from August 1984 to January 1999.
Berkeley, CA 94720

V. Orville Wright....................    78              Director of Calpine since  January 1997.  Mr. Wright served
                                                         in  various  positions  with  MCI   Communications   Corp.,
                                                         including  Vice  Chairman  and Co-Chief  Executive  Officer
                                                         from  1988 to  1991,  Vice  Chairman  and  Chief  Executive
                                                         Officer  from  1985  to  1987,   and  President  and  Chief
                                                         Operating Officer from 1975 to 1985.

Robert D. Kelly......................    41              Senior Vice  President - Finance of Calpine  since  January
                                                         1998  and Vice  President  -  Finance  from  April  1994 to
                                                         January 1998.
</TABLE>





                                      I-2
<PAGE>   12
2. DIRECTORS AND EXECUTIVE OFFICERS OF MERGER SUBSIDIARY. The following table
sets forth the name, age, business address and present principal occupation or
employment, and material occupations, positions, offices or employments for the
past five years of each director and executive officer of Calpine. Each such
person is a citizen of the United States of America. Unless otherwise indicated
below, the business address of each person is c/o Calpine Corporation, 50 West
San Fernando Street, San Jose, California, 95113. Unless otherwise indicated,
each occupation set forth opposite an individual's name refers to employment
with Calpine.


<TABLE>
<CAPTION>
                                                                      Present Principal Occupation
            Name and                                               or Employment; Material Positions
        Business Address            Age                               Held During Past Five Years
        ----------------            ---                               ---------------------------
<S>                                <C>               <C>
Peter Cartwright................   69                Chairman of Board,  President and Chief  Executive  Officer of
                                                     Merger  Subsidiary  since  its  incorporation  on  August  23,
                                                     1999.  Director of Calpine  since 1984,  Chairman of the Board
                                                     of  Calpine  since   September   1996,   President  and  Chief
                                                     Executive Officer of Calpine since 1984.

Ann B. Curtis...................   48                Vice  President,  Chief  Financial  Officer and  Secretary  of
                                                     Merger  Subsidiary  since  its  incorporation  on  August  23,
                                                     1999.  Director of Calpine since  September 1996 and Executive
                                                     Vice  President of Calpine since August 1998.  From  September
                                                     1992 until August 1998,  Ms. Curtis was Senior Vice  President
                                                     of Calpine.

Thomas R. Mason.................   55                Executive  Vice  President  of  Merger  Subsidiary  since  its
                                                     incorporation  on August 23, 1999.  Executive  Vice  President
                                                     of Calpine  since  August  1998.  From March 1998 until August
                                                     1998,  Mr. Mason was Senior Vice  President of Calpine.  Prior
                                                     to  joining  Calpine,   Mr.  Mason  was  President  and  Chief
                                                     Operating  Officer of CalEnergy  Operating  Services,  Inc., a
                                                     wholly-owned   subsidiary  of  MidAmerican   Energy   Holdings
                                                     Company.

John T. King....................   34                Vice President of Merger  Subsidiary  since its  incorporation
                                                     on  August  23,  1999.  Vice  President-Business   Development
                                                     since  September  1997 and employee of Calpine since  February
                                                     1995.   From  1994  to  February  1995,  Mr.  King  was  Chief
                                                     Operating Officer of Charter Media, Inc.
</TABLE>

                                      I-3
<PAGE>   13

<TABLE>
<S>                                <C>               <C>
Robert D. Kelly.................   41                Vice President of Merger  Subsidiary  since its  incorporation
                                                     on August  23,  1999.  Senior  Vice  President  -  Finance  of
                                                     Calpine  since  January 1998 and Vice  President-Finance  from
                                                     April 1994 to January 1998.

Charles B. Clark, Jr............   51                Controller of Merger  Subsidiary  since its  incorporation  on
                                                     August 23, 1999.  Vice  President and Corporate  Controller of
                                                     Calpine  since May 1999.  From  February  1999 to April  1999,
                                                     Director   of   Business   Services   for   Geysers,   Calpine
                                                     Corporation.  From March 1998 to November  1998, Mr. Clark was
                                                     Chief  Financial  Officer of Hobbs Group,  LLC.  From February
                                                     1997  to   February   1998,   Mr.   Clark  was   Senior   Vice
                                                     President-Finance  and Administration of CNF Industries,  Inc.
                                                     and  from  May  1988 to  January  1997,  Mr.  Clark  was  Vice
                                                     President and Chief Financial  Officer of Century  Contractors
                                                     West, Inc. (a predecessor of CNF Industries, Inc.)

Lisa M. Bodensteiner............   37                Assistant   Secretary   of   Merger   Subsidiary   since   its
                                                     incorporation  on August 23, 1999,  Vice President and General
                                                     Counsel of Calpine  since April 1999.  From  February  1998 to
                                                     March 1999, Ms.  Bodensteiner was Calpine's  Assistant General
                                                     Counsel and from  February 1996 to February 1998 was Associate
                                                     Counsel.  Prior to joining  Calpine,  Ms.  Bodensteiner was an
                                                     attorney  for Thelen,  Marrin,  Johnson & Bridges (now Thelen,
                                                     Reid & Priest).
</TABLE>

         None of the executive officers and directors of Calpine or Merger
Subsidiary currently is a director of, or holds any position with, the Company
or any of its subsidiaries. To the knowledge of Calpine and Merger Subsidiary,
none of Calpine's or Merger Subsidiary's directors, executive officers,
affiliates or associates beneficially owns any equity securities, or rights to
acquire any equity securities, of the Company and none has been involved in any
transactions with the Company or any of its directors, executive officers,
affiliates or associates which are required to be disclosed pursuant to the
rules and regulations of the Commission.



                                      I-4

<PAGE>   1
                                                                     Exhibit (1)


                             Joint Filing Agreement

                  The undersigned acknowledge and agree that the foregoing
statement on Schedule 13D is filed on behalf of each of the undersigned and that
all subsequent amendments to this statement shall be filed on behalf of each of
the undersigned without the necessity of filing additional joint filing
agreements. The undersigned acknowledge that each shall be responsible for the
timely filing of such amendments, and for the completeness and accuracy of the
information concerning it contained therein, but shall not be responsible for
the completeness and accuracy of the information concerning the others, except
to the extent that it knows or has reason to believe that such information is
inaccurate.

                  This Agreement may be executed counterparts and each of such
counterparts taken together shall constitute one and the same instrument.

Dated:  September 7, 1999


                         CALPINE EAST ACQUISITION CORP.


                         By: /s/  Ann B. Curtis
                             ------------------
                           Name:      Ann B. Curtis
                           Title:     Vice President, Chief Financial Officer
                                      and Secretary


                         CALPINE CORPORATION


                         By: /s/  Ann B. Curtis
                             ------------------
                           Name:      Ann B. Curtis
                           Title:     Executive Vice President




<PAGE>   1
                                                                     Exhibit (2)










                          AGREEMENT AND PLAN OF MERGER



                              DATED AUGUST 26, 1999



                                      AMONG



                              CALPINE CORPORATION,



                         CALPINE EAST ACQUISITION CORP.



                                       AND



                       COGENERATION CORPORATION OF AMERICA



<PAGE>   2
                                TABLE OF CONTENTS

                          AGREEMENT AND PLAN OF MERGER

<TABLE>
<S>                                                                                               <C>
ARTICLE I        THE MERGER                                                                        4
   Section 1.1    The Merger                                                                       5
   Section 1.2    Effective Time                                                                   5
   Section 1.3    Effects of the Merger                                                            5
   Section 1.4    Charter and By-Laws; Directors and Officers                                      5
   Section 1.5    Conversion of Securities                                                         5
   Section 1.6    Payment Agent                                                                    7
   Section 1.7    Transfer Taxes; Withholding                                                      7
   Section 1.8    Return of Payment Fund                                                           8
   Section 1.9    No Further Ownership Rights in Company Common Stock                              8
   Section 1.10   Closing of Company Transfer Books                                                8
   Section 1.11   Lost Certificates                                                                8
   Section 1.12   Further Assurances                                                               8
   Section 1.13   Closing                                                                          9
ARTICLE II       REPRESENTATIONS AND WARRANTIES OF PARENT AND SUB                                  9
   Section 2.1    Organization, Standing and Power                                                 9
   Section 2.2    Authority                                                                        9
   Section 2.3    Consents and Approvals; No Violation                                            10
   Section 2.4    Information Supplied                                                            11
   Section 2.5    Actions and Proceedings                                                         11
   Section 2.6    Operations of Sub                                                               12
   Section 2.7    Brokers                                                                         12
   Section 2.8    Financing                                                                       12
ARTICLE III      REPRESENTATIONS AND WARRANTIES OF THE COMPANY                                    12
   Section 3.1    Organization, Standing and Power                                                12
   Section 3.2    Capital Structure                                                               12
   Section 3.3    Authority                                                                       13
   Section 3.4    Consents and Approvals; No Violation                                            14
   Section 3.5    SEC Documents and Other Reports                                                 15
   Section 3.6    Information Supplied                                                            15
   Section 3.7    Absence of Certain Changes or Events                                            16
   Section 3.8    Permits and Compliance                                                          16
   Section 3.9    Tax Matters                                                                     17
   Section 3.10   Actions and Proceedings                                                         19
   Section 3.11   Certain Agreements                                                              19
   Section 3.12   ERISA                                                                           19
   Section 3.13   Compliance with Worker Safety and Environmental Laws                            21
   Section 3.14   Labor Matters                                                                   21
   Section 3.15   State Takeover Statute                                                          21
   Section 3.16   Required Vote of Company Stockholders                                           21
   Section 3.17   Brokers                                                                         22
   Section 3.18   Opinion of Financial Advisor                                                    22
   Section 3.19   Utility Regulation                                                              22
   Section 3.20   Insurance                                                                       22
   Section 3.21   Related Party Transactions                                                      22
ARTICLE IV       COVENANTS OF THE COMPANY                                                         23
   Section 4.1    Conduct of Business Pending the Merger                                          23
   Section 4.2    No Solicitation                                                                 25
</TABLE>



<PAGE>   3

<TABLE>
<S>                                                                                              <C>
ARTICLE V       ADDITIONAL AGREEMENTS                                                             27
   Section 5.1    Stockholder Meeting                                                             27
   Section 5.2    Preparation of the Proxy Statement and Schedule 13e-3                           27
   Section 5.3    Access to Information                                                           28
   Section 5.4    Fees and Expenses                                                               28
   Section 5.5    Best Efforts                                                                    29
   Section 5.6    Public Announcements                                                            30
   Section 5.7    Real Estate Transfer and Gains Tax                                              30
   Section 5.8    Indemnification; Directors and Officers Insurance                               30
   Section 5.9    Notification of Certain Matters                                                 31
   Section 5.10   Employee Benefit Plans and Agreements                                           32
   Section 5.11   Performance by Sub                                                              32
   Section 5.12   Additional Consents and Approvals                                               32
ARTICLE VI      CONDITIONS PRECEDENT TO THE MERGER                                                33
   Section 6.1    Conditions to Each Party's Obligation to Effect the Merger                      33
   Section 6.2    Conditions to Obligation of the Company to Effect the Merger                    34
   Section 6.3    Conditions to Obligations of Parent and Sub to Effect the Merger                34
ARTICLE VII     TERMINATION, AMENDMENT AND WAIVER                                                 35
   Section 7.1    Termination                                                                     35
   Section 7.2    Effect of Termination                                                           36
   Section 7.3    Amendment                                                                       36
   Section 7.4    Waiver                                                                          37
ARTICLE VIII    GENERAL PROVISIONS                                                                37
   Section 8.1    Non-Survival of Representations and Warranties                                  37
   Section 8.2    Notices                                                                         37
   Section 8.3    Interpretation                                                                  38
   Section 8.4    Counterparts                                                                    38
   Section 8.5    Entire Agreement; No Third-Party Beneficiaries                                  38
   Section 8.6    Governing Law                                                                   38
   Section 8.7    Assignment                                                                      38
   Section 8.8    Severability                                                                    38
   Section 8.9    Enforcement of this Agreement                                                   38
   Section 8.10   Consent to Jurisdiction                                                         39
</TABLE>



                                       3
<PAGE>   4
                          AGREEMENT AND PLAN OF MERGER


                  THIS AGREEMENT AND PLAN OF MERGER, dated as of August 26, 1999
(the "Agreement"), is executed by and among CALPINE CORPORATION, a Delaware
corporation ("Parent"), CALPINE EAST ACQUISITION CORP., a Delaware corporation
and a subsidiary of Parent ("Sub"), and COGENERATION CORPORATION OF AMERICA, a
Delaware corporation (the "Company") (Sub and the Company being hereinafter
collectively referred to as the "Constituent Corporations").


                                    RECITALS:


           WHEREAS, the respective Boards of Directors of Parent, Sub and the
  Company have approved the merger (the "Merger") of Sub with and into the
  Company, on the terms and subject to the conditions set forth in this
  Agreement, whereby each outstanding share of common stock, par value $.01 per
  share, of the Company (the "Company Common Stock") not owned by Parent, Sub or
  the Company will be converted into the right to receive $25.00 per share (the
  "Merger Price") in cash pursuant to this Agreement;

           WHEREAS, simultaneously with the execution and delivery of this
  Agreement, Parent and NRG Energy, Inc., a Delaware corporation (the "Principal
  Company Stockholder"), are entering into an agreement (the "Company
  Stockholder Agreement" and together with this Agreement, the "Transaction
  Documents") pursuant to which the Principal Company Stockholder and Parent or
  Sub have agreed to take specified actions in connection with the transactions
  contemplated by this Agreement;

           WHEREAS, the Board of Directors of the Company has duly and
  unanimously adopted resolutions approving the transactions contemplated by the
  Transaction Documents in form and substance sufficient to render Section 203
  of the Delaware General Corporation Law (the "DGCL") inapplicable to Parent
  and Sub; and

           WHEREAS, Parent, Sub and the Company desire to make certain
  representations, warranties, covenants and agreements in connection with the
  Merger and also to prescribe various conditions to the Merger.

           NOW, THEREFORE, in consideration of the premises, representations,
  warranties and agreements herein contained, the parties agree as follows:


                                    ARTICLE I

                                   THE MERGER

                                       4
<PAGE>   5
                  Section 1.1 The Merger. Upon the terms and subject to the
conditions hereof, and in accordance with the DGCL, Sub shall be merged with and
into the Company at the Effective Time (as hereinafter defined). Following the
Merger, the separate corporate existence of Sub shall cease and the Company
shall continue as the surviving corporation (the "Surviving Corporation") and
shall succeed to and assume all the rights and obligations of Sub in accordance
with the DGCL.

                  Section 1.2 Effective Time. The Merger shall become effective
when a Certificate of Merger (the "Certificate of Merger"), executed in
accordance with the relevant provisions of the DGCL, is filed with the Secretary
of State of the State of Delaware; provided, however, that, upon the mutual
consent of the Constituent Corporations, the Certificate of Merger may provide
for a later date or time of effectiveness of the Merger. When used in this
Agreement, the term "Effective Time" shall mean the date and time at which the
Certificate of Merger is accepted for record or such later date or time
established by the Certificate of Merger. The filing of the Certificate of
Merger shall be made on the date of the Closing (as hereinafter defined).

                  Section 1.3 Effects of the Merger. The Merger shall have the
effects set forth in Section 259 of the DGCL.

                  Section 1.4 Certificate of Incorporation and By-Laws;
Directors and Officers.

                  (a) Certificate of Incorporation and By-Laws. The Certificate
of Incorporation of the Company shall be amended as set forth in Exhibit A to
this Agreement (the "Amendment"), which amendment shall be effective as soon as
practicable after the Company's shareholders have approved the amendment and
prior to the Effective Time. At the Effective Time, the Certificate of
Incorporation of the Company, as in effect immediately prior to the Effective
Time, shall be amended and restated to read as did the Certificate of
Incorporation of Sub immediately prior to the Effective Time. At the Effective
Time, the By-Laws of the Company, as in effect immediately prior to the
Effective Time, shall be amended and restated to read as did the By-Laws of Sub
immediately prior to the Effective Time. As so amended and restated, such
Certificate of Incorporation and By-Laws of the Company shall be the Certificate
of Incorporation and By-Laws of the Surviving Corporation until thereafter
changed or amended as provided therein or by applicable law.

                  (b) Directors and Officers. From and after the Effective Time,
the directors of Sub at the Effective Time shall be the directors of the
Surviving Corporation, until the earlier of their resignation or removal or
until their respective successors are duly elected and qualified, as the case
may be. From and after the Effective Time, the officers of the Sub at the
Effective Time shall be the officers of the Surviving Corporation, until the
earlier of their resignation or removal or until their respective successors are
duly elected and qualified, as the case may be.

                  Section 1.5 Conversion of Securities. As of the Effective
Time, by virtue of the Merger and without any action on the part of Sub, the
Company or the holders of any securities of the Constituent Corporations:

                  (a) Each issued and outstanding share of common stock, without
par value, of Sub shall be converted into one validly issued, fully paid and
nonassessable share of common stock of the Surviving Corporation with the same
rights, powers and privileges as the shares so converted

                                       5
<PAGE>   6
and shall constitute the only outstanding shares of capital stock of the
Surviving Corporation.

                  (b) All shares of Company Common Stock that are held in the
treasury of the Company or owned by Parent, Sub or any Subsidiary (as defined in
Section 2.1) of either of them shall be canceled and no cash or other
consideration shall be delivered in exchange therefor.

                  (c) Each share of Company Common Stock issued and outstanding
immediately prior to the Effective Time (other than shares to be canceled in
accordance with Section 1.5(b) and Dissenting Shares (as defined in Section
1.5(e)) shall be converted into the right to receive an amount of cash equal to
the Merger Price without interest. All such shares of Company Common Stock, when
so converted, shall no longer be outstanding and shall automatically be canceled
and retired and each holder of a certificate (the "Certificate") formerly
representing any such shares shall cease to have any rights with respect
thereto, except the right to receive the cash to be paid to such holder pursuant
to Article I hereof (the "Merger Consideration") upon the surrender of a
Certificate or Certificates in accordance with Section 1.6 hereof.

                  (d) (i) At the Effective Time, each outstanding option to
purchase Company Common Stock (each a "Company Stock Option") granted under the
Company Stock Plans (as defined herein), whether or not then exercisable, shall
be cancelled and each holder of a cancelled Company Stock Option shall be
entitled to receive at the Effective Time or as soon as practicable thereafter
from the Company, upon execution and delivery to the Payment Agent (as defined
in Section 1.6 below) of an option termination agreement, in form and substance
reasonably acceptable to Parent in consideration for the cancellation of such
Company Stock Option an amount in cash (the "Option Consideration") equal to (x)
the number of shares of Company Common Stock previously subject to such Company
Stock Option that but for the cancellation thereof pursuant to the provisions of
this Section 1.5(d) would have been currently exercisable (after giving effect
to any acceleration of vesting pursuant to the terms of such Company Stock
Option as a result of the consummation of the Merger), multiplied by (y) the
excess, if any, of the Merger Price over the exercise price per share of Company
Common Stock previously subject to such Company Stock Option (such payment to be
net of applicable withholding taxes).

                      (ii) Except as provided herein or as otherwise agreed to
by the parties and to the extent permitted by the Company Stock Plans, (x) the
Company Stock Plans shall terminate as of the Effective Time and the provisions
in any other plan, program or arrangement providing for the issuance or grant of
any other interest in respect of the capital stock of the Company or any of its
Subsidiaries shall be deleted as of the Effective Time and (y) the Company shall
use all reasonable efforts to ensure that following the Effective Time no holder
of Company Stock Options or any participant in the Company Stock Plans or any
other plans, programs or arrangements shall have any right thereunder to acquire
any equity securities of the Company, the Surviving Corporation or any
subsidiary thereof.

                  (e) Notwithstanding anything in this Agreement to the
contrary, shares ("Dissenting Shares") of Company Common Stock that are
outstanding immediately prior to the Effective Time and that are held by Persons
who are entitled to demand and have properly demanded dissention rights with
respect to such Dissenting Shares pursuant to, and who comply in all respects
with, Section 262 of the DGCL ("Section 262") shall not be converted into the
Merger Consideration

                                       6
<PAGE>   7
as provided in Section 1.5(c), but rather the holders of Dissenting Shares shall
be entitled to payment of the fair market value of such Dissenting Shares in
accordance with Section 262; provided, however, that if any holder of Dissenting
Shares shall fail to perfect or otherwise shall waive, withdraw or lose the
right to Dissenting under Section 262, then the right of such holder to be paid
the fair value of such holder's Dissenting Shares shall cease and such
Dissenting Shares shall be treated as if they had been converted as of the
Effective Time into the Merger Consideration, as provided in Section 1.5(c). The
Company shall serve prompt notice to Parent of any demands received by the
Company for dissenter's rights with respect to any shares of Company Common
Stock, and Parent shall have the right to participate in and direct all
negotiations and proceedings with respect to such demands. The Company shall
not, except with the prior written consent of Parent, make any payment with
respect to, or settle or offer to settle, any such demands, or agree to do any
of the foregoing.

                  Section 1.6 Payment Agent.

                  (a) Exchange of Certificates. Parent shall authorize a
commercial bank or trust company (or such other Person or Persons as shall be
reasonably acceptable to Parent and the Company) to act as Payment Agent
hereunder (the "Payment Agent"). As soon as practicable after the Effective
Time, Parent shall deposit with the Payment Agent, in trust for the holders of
shares of Company Common Stock converted in the Merger and holders of Company
Stock Options, an amount of cash equal to or exceeding the aggregate Merger
Consideration to be paid to holders of Company Common Stock pursuant to Article
I hereof and any Option Consideration to be paid to holders of Company Stock
Options pursuant to the terms of Section 1.5(d) (such amount hereinafter the
"Payment Fund").

                  (b) Exchange Procedures. Parent shall instruct the Payment
Agent, as soon as practicable after the Effective Time, to mail to each record
holder of a Certificate or Certificates a letter of transmittal, which shall
specify that delivery shall be effected, and risk of loss and title to the
Certificates shall pass, only upon actual delivery of the Certificates to the
Payment Agent, and shall contain instructions for use in effecting the surrender
of the Certificates in exchange for the Merger Consideration. Upon surrender for
cancellation to the Payment Agent of all Certificates held by any record holder
of a Certificate, together with such letter of transmittal, duly executed, the
holder of such Certificate shall be entitled to receive in exchange therefor a
check representing the Merger Consideration, and any Certificate so surrendered
shall forthwith be canceled. Holders of Company Stock Options shall receive
payment, if any, for such Company Stock Options pursuant to Section 1.5(d).

                  Section 1.7 Transfer Taxes; Withholding. If any Merger
Consideration is to be paid to any Person other than to the Person named in the
Certificate surrendered in exchange therefor, it shall be a condition of such
exchange that the Certificate so surrendered shall be properly endorsed and
otherwise in proper form for transfer and that the Person requesting such
exchange shall pay to the Payment Agent any transfer or other taxes required by
reason of the payment of the Merger Consideration to a Person other than to the
Person named in the Certificate surrendered, or shall establish to the
satisfaction of the Payment Agent that such tax has been paid or is not
applicable. Parent or the Payment Agent shall be entitled to deduct and withhold
from the consideration otherwise payable pursuant to this Agreement to any
holder of shares of Company

                                       7
<PAGE>   8
Common Stock or holder of a Company Stock Option such amounts as Parent or the
Payment Agent is required to deduct and withhold with respect to the making of
such payment under the Internal Revenue Code of 1986, as amended (the "Code") or
under any provision of state, local or foreign tax law. To the extent that
amounts are so withheld by Parent or the Payment Agent, such withheld amounts
shall be treated for all purposes of this Agreement as having been paid to the
holder of the shares of Company Common Stock or the holder of a Company Stock
Option in respect of which such deduction and withholding was made by Parent or
the Payment Agent. For purposes of this Agreement, "Person" shall mean an
individual, corporation, partnership, limited liability company, joint venture,
association, trust, unincorporated organization or other entity.

                  Section 1.8 Return of Payment Fund. Any portion of the Payment
Fund which remains undistributed for six months after the Effective Time shall
be delivered to Parent, upon demand of Parent, and any such former stockholders
who have not theretofore complied with this Article I and holders of Company
Stock Options who have not yet received the Option Consideration shall
thereafter look only to Parent for payment of their claim for any Merger
Consideration or Option Consideration, as the case may be. Neither Parent nor
the Surviving Corporation shall be liable to any former holder of Company Common
Stock or holder of a Company Stock Option for any cash held in the Payment Fund
which is delivered to a public official pursuant to any applicable abandoned
property, escheat or similar law.

                  Section 1.9 No Further Ownership Rights in Company Common
Stock. The payment of the Merger Consideration upon surrender of any Certificate
shall be deemed to constitute full satisfaction of all rights pertaining to the
shares of Company Common Stock represented by such Certificate.

                  Section 1.10 Closing of Company Transfer Books. At the
Effective Time, the stock transfer books of the Company shall be closed and no
transfer of shares of Company Common Stock shall thereafter be made on the
records of the Company. If, after the Effective Time, Certificates are presented
to the Surviving Corporation, the Payment Agent or the Parent, such Certificates
shall be canceled and exchanged as provided in this Article I.

                  Section 1.11 Lost Certificates. If any Certificate shall have
been lost, stolen or destroyed, upon the making of an affidavit of that fact by
the Person claiming such Certificate to be lost, stolen or destroyed and, if
required by Parent or the Payment Agent, the posting by such Person of a bond,
in such reasonable amount as Parent or the Payment Agent may direct as indemnity
against any claim that may be made against them with respect to such
Certificate, the Payment Agent will pay the Merger Consideration in exchange for
such lost, stolen or destroyed Certificate.

                  Section 1.12 Further Assurances. If at any time after the
Effective Time the Surviving Corporation shall consider or be advised that any
deeds, bills of sale, assignments or assurances or any other acts or things are
necessary, desirable or proper (a) to vest, perfect or confirm, of record or
otherwise, in the Surviving Corporation its right, title or interest in, to or
under any of the rights, privileges, powers, franchises, properties or assets of
either of the Constituent Corporations, or (b) otherwise to carry out the
purposes of this Agreement, the Surviving Corporation and its proper officers
and directors or their designees shall be authorized to execute and deliver, in
the name and on behalf of either of the Constituent Corporations, all such
deeds, bills of sale, assignments and assurances and to do, in the name and on
behalf of either Constituent

                                       8
<PAGE>   9
Corporation, all such other acts and things as may be necessary, desirable or
proper to vest, perfect or confirm the Surviving Corporation's right, title or
interest in, to or under any of the rights, privileges, powers, franchises,
properties or assets of such Constituent Corporation and otherwise to carry out
the purposes of this Agreement.

                  Section 1.13 Closing. The closing of the transactions
contemplated by this Agreement (the "Closing") and all actions specified in this
Agreement to occur at the Closing shall take place at the offices of Kaplan,
Strangis and Kaplan, P.A., 5500 Norwest Center, 90 South Seventh Street,
Minneapolis, Minnesota, at 10:00 a.m., local time, no later than the second
business day following the day on which the last of the conditions set forth in
Article VI shall have been fulfilled or waived (if permissible) or at such other
time and place as Parent and the Company shall agree.


                                   ARTICLE II

                REPRESENTATIONS AND WARRANTIES OF PARENT AND SUB

                  Parent and Sub represent and warrant to the Company as
follows:

                  Section 2.1 Organization, Standing and Power. Each of Parent
and Sub is a corporation duly organized, validly existing and in good standing
under the laws of its place of incorporation and has the requisite corporate
power and authority to carry on its business as now being conducted. Parent is
duly qualified to do business, and is in good standing in each jurisdiction
where the character of the properties owned or held under lease by it or the
nature of its activities makes such qualification necessary, except where the
failure to be so qualified would not, individually or in the aggregate, have a
Material Adverse Effect (as hereinafter defined) on Parent. For purposes of this
Agreement (a) "Material Adverse Change" or "Material Adverse Effect" means, when
used with respect to Parent or the Company, as the case may be, any change or
effect that is or could reasonably be expected (as far as can be foreseen at the
time) to be materially adverse to the business, assets, liabilities, financial
condition or results of operations of Parent and its Subsidiaries, taken as a
whole, or the Company and its Subsidiaries, taken as a whole, as the case may
be; provided, however, that in determining whether a Material Adverse Change or
Material Adverse Effect has occurred with respect to either referenced party,
any change or effect, to the extent it is attributable to changes in prevailing
interest rates or to any change in general economic conditions affecting
companies in industries similar to the industries in which the Company and its
Subsidiaries or Parent and its Subsidiaries, as the case may be, operate, shall
not be considered when determining if a Material Adverse Change or Material
Adverse Effect has occurred; and (b) "Subsidiary" means any corporation,
partnership, limited liability company, joint venture or other legal entity of
which Parent or the Company, as the case may be (either alone or through or
together with any other Subsidiary), owns, directly or indirectly, 50% or more
of the stock or other equity interests the holders of which are generally
entitled to vote for the election of the board of directors or other governing
body of such corporation, partnership, limited liability company, joint venture
or other legal entity.

                  Section 2.2 Authority. On or prior to the date of this
Agreement, Parent and Sub

                                       9
<PAGE>   10
have each approved the Transactions and the Transaction Documents. Each of
Parent and Sub has the requisite corporate power and authority to enter into the
Transaction Documents and to consummate the transactions contemplated hereby.
The execution and delivery of the Transaction Documents by Parent and Sub to
which it is a party and the consummation by Parent and Sub of the transactions
contemplated hereby have been duly and validly authorized by all necessary
corporate action on the part of Parent or Sub, as the case may be, subject to
the filing of the Certificate of Merger with the Secretary of State of the State
of Delaware. The Transaction Documents to which it is a party have been duly
executed and delivered by Parent and Sub and constitute the valid and binding
obligations of each of Parent or Sub, as the case may be, enforceable against
them in accordance with its terms, except as the enforceability hereof may be
limited by bankruptcy, insolvency, moratorium or other similar laws affecting
the enforcement of creditors' rights generally and to judicial limitations on
the enforcement of specific performance and other equitable remedies.

                  Section 2.3 Consents and Approvals; No Violation. Assuming
that all consents, approvals, authorizations and other actions described in this
Section 2.3 have been obtained and all filings and obligations described in this
Section 2.3 have been made, the execution and delivery of the Transaction
Documents and the consummation of the transactions contemplated hereby and
compliance with the provisions hereof will not result in any violation of, or
default (with or without notice or lapse of time, or both) under, or give to
others a right of termination, cancellation or acceleration of any obligation or
the loss of a material benefit under, or result in the creation of any lien,
security interest, charge or encumbrance upon any of the properties or assets of
Parent or any of its Subsidiaries under, any provision of (i) the Certificate of
Incorporation or the By-Laws of Parent or the Certificate of Incorporation or
By-Laws of Sub, (ii) any provision of the comparable charter or organization
documents of any of Parent's Subsidiaries, (iii) any loan or credit agreement,
note, bond, mortgage, indenture, lease or other agreement, instrument, permit,
concession, franchise or license applicable to Parent or any of its Subsidiaries
or (iv) any judgment, order, decree, statute, law, ordinance, rule or regulation
applicable to Parent or any of its Subsidiaries or any of their respective
properties or assets, other than, in the case of clauses (ii), (iii) or (iv),
any such violations, defaults, rights, liens, security interests, charges or
encumbrances that, individually or in the aggregate, would not have a Material
Adverse Effect on Parent, materially impair the ability of Parent or Sub to
perform their respective obligations hereunder or prevent the consummation of
any of the transactions contemplated hereby. No filing or registration with, or
authorization, consent or approval of, any domestic (federal and state), foreign
or supranational court, commission, governmental body, regulatory agency,
authority or tribunal (a "Governmental Entity") is required by or with respect
to Parent or any of its Subsidiaries in connection with the execution, delivery
and performance of any Transaction Agreement by Parent or Sub or is necessary
for the consummation of the Transactions, except for (i) in connection, or in
compliance, with the provisions of the Hart-Scott-Rodino AntiTrust Improvement
Act of 1976 (the "HSR Act") and the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), (ii) the final order of the Federal Energy Regulatory
Commission ("FERC") approving the transfer of jurisdictional facilities under
Section 203 of the Federal Power Act in connection with the power generating
project of one of the Company's subsidiaries in Parlin, New Jersey (the
"Regulatory Approval"), (iii) in connection, or in compliance, with the
provisions of the New Jersey Industrial Site Recovery Act and the New Jersey
Environmental Cleanup Responsibility Act (the "Applicable New Jersey Law"), (iv)
the filing of the Certificate of Merger with the Secretary of State of the State
of Delaware and appropriate documents with the relevant authorities of other
states in which the Company or any of its Subsidiaries is

                                       10
<PAGE>   11

qualified to do business, (v) such filings, authorizations, orders, notices and
approvals as may be required by state takeover laws (the "State Takeover
Approvals"), and (vi) such consents, orders, authorizations, registrations,
declarations and filings the failure of which to be obtained or made would not,
individually or in the aggregate, have a Material Adverse Effect on Parent, or
materially impair the ability of Parent or Sub to perform its obligations
hereunder or prevent the consummation of any of the transactions contemplated
hereby. Neither the Parent nor the Sub is an electric utility or an electric
utility holding company or companies, or any affiliate of either, in each case
as those terms are utilized by the FERC in regulations or orders implementing
the Public Utility Regulatory Policies Act of 1978, as amended, and its
successors ("PURPA"). Consummation of the Merger will not result in the loss of
the status of any project as a "Qualifying Facility" as defined under PURPA in
which the Company or any of its Subsidiaries, directly or indirectly, have an
equity interest.

                  Section 2.4 Information Supplied. None of the information to
be supplied by Parent or Sub for inclusion or incorporation by reference in the
Schedule 13e-3 to be filed pursuant to the Exchange Act in connection with the
transactions contemplated by the Transaction Documents (together with any
amendments or supplements thereto, the "Schedule 13e-3") or the proxy statement
relating to the Stockholder Meeting (as hereinafter defined) (together with any
amendments or supplements thereto, the "Proxy Statement") will, (i) in the case
of the Schedule 13e-3, at the time of its filing, at the time of the
dissemination of the Schedule 13e-3 and until the Effective Time, contain any
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary in order to make the statements therein not
misleading or (ii) in the case of the Proxy Statement and at the time of the
mailing of the Proxy Statement and at the time of the Stockholder Meeting,
contain any untrue statement of a material fact or omit to state any material
fact required to be stated therein or necessary in order to make the statements
therein, in light of the circumstances under which they are made, not
misleading, except that no representation is made by Parent or Sub with respect
to statements made or incorporated by reference therein based on information
supplied by or on behalf of the Company or NRG Energy, Inc. for inclusion or
incorporation by reference therein.

                  Section 2.5 Actions and Proceedings. As of the date of this
Agreement, there are no outstanding orders, judgments, injunctions, awards or
decrees of any Governmental Entity against or involving Parent or any of its
Subsidiaries, or against or involving any of the present or former directors,
officers, employees, consultants, agents or stockholders of Parent or any of its
Subsidiaries, as such, or any of its or their properties, assets or business
that, individually or in the aggregate, would materially impair the ability of
Parent to perform its obligations hereunder. As of the date of this Agreement,
there are no actions, suits or claims or legal, administrative or arbitrative
proceedings or investigations pending or, to the Knowledge of Parent, threatened
against or involving Parent or any of its Subsidiaries or any of its or their
present or former directors, officers, employees, consultants, agents or
stockholders, as such, or any of its or their properties, assets or business
that, individually or in the aggregate, would materially impair the ability of
Parent to perform its obligations hereunder. As of the date hereof, there are no
actions, suits, labor disputes or other litigation, legal or administrative
proceedings or governmental investigations pending or, to the Knowledge of
Parent, threatened against or affecting Parent or any of its Subsidiaries or any
of its or their present or former officers, directors, employees, consultants,
agents or stockholders, as such, or any of its or their properties, assets or
business relating to the transactions contemplated by this Agreement. For
purposes of this Agreement, "Knowledge of Parent" means the actual knowledge of

                                       11
<PAGE>   12
the executive officers of Parent after due inquiry.

                  Section 2.6 Operations of Sub. Sub is a direct subsidiary of
Parent, was formed solely for the purpose of engaging in the transactions
contemplated hereby, has engaged in no other business activities and has
conducted its operations only as contemplated hereby.

                  Section 2.7 Brokers. No broker, investment banker or other
Person is entitled to any broker's, finder's or other similar fee or commission
in connection with the transaction contemplated by this Agreement based upon the
arrangements made by or on behalf of Parent or Sub.

                  Section 2.8 Financing. Parent has sufficient capital resources
necessary to perform its obligations under the Transaction Documents, including
but not limited to the advances under Section 5.11.


                                   ARTICLE III

                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

                  The Company represents and warrants to Parent and Sub that,
subject to the disclosures set forth in the letter dated as of the date hereof
and delivered on the date hereof by Company to Parent (the "Company Letter"):

                  Section 3.1 Organization, Standing and Power. The Company is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware and has the requisite corporate power and authority to
carry on its business as now being conducted. Each Subsidiary of the Company is
duly organized, validly existing and in good standing under the laws of the
jurisdiction in which it is organized and has the requisite corporate (in the
case of a Subsidiary that is a corporation) or other power and authority to
carry on its business as now being conducted, except where the failure to be so
organized, existing or in good standing or to have such power or authority would
not, individually or in the aggregate, have a Material Adverse Effect on the
Company. The Company and each of its Subsidiaries are duly qualified to do
business, and are in good standing, in each jurisdiction where the character of
their properties owned or held under lease or the nature of their activities
makes such qualification necessary, except where the failure to be so qualified
would not, individually or in the aggregate, have a Material Adverse Effect on
the Company. The Company has delivered or otherwise made available to Parent
true and complete and correct copies of the Company's Certificate of
Incorporation and By-laws and the certificate of incorporation, by-laws or other
constitutive documents of each of the Company's Subsidiaries, in each case as
amended to the date of this Agreement.

                  Section 3.2 Capital Structure. The authorized capital stock of
the Company consists of 50,000,000 shares of Company Common Stock and 20,000,000
shares of undesignated preferred stock, par value $.01 per share ("Company
Preferred Stock"). As of the date of this Agreement, (i) 6,857,269 shares of
Company Common Stock were issued and outstanding, all of which were duly
authorized, validly issued, fully paid and nonassessable and free of preemptive

                                       12
<PAGE>   13
rights, (ii) 39,800 shares of Company Common Stock were held in the treasury of
the Company or by Subsidiaries of the Company, (iii) 877,000 shares of Company
Common Stock were reserved for issuance pursuant to outstanding Company Stock
Options under the Company's stock plans described under Section 3.2 of the
Company Letter (collectively, the "Company Stock Plans"), and (iv) 797,000
Company Stock Options are currently exercisable or will become exercisable upon
consummation of the Transactions. A true and complete list of the options (and
their exercise prices) referred to in clause (iv) above that are entitled to
Option Consideration are set forth on Section 3.2 of the Company Letter. No
Company Stock Options have been granted since May 31, 1999. The Company Stock
Plans are the only benefit plans of the Company or its Subsidiaries under which
any securities of the Company or any of its Subsidiaries are issuable. No shares
of Company Preferred Stock are outstanding. As of the date of this Agreement,
except as set forth above no shares of capital stock or other voting securities
of the Company or any Subsidiary were issued, reserved for issuance or
outstanding. Except as set forth in this Section 3.2, there are no outstanding
equity equivalents or interests in the ownership or earnings of the Company or
any Subsidiary and there are no options, warrants, calls, rights or agreements
to which the Company or any of its Subsidiaries is a party or by which any of
them is bound obligating the Company or any of its Subsidiaries to issue,
deliver or sell, or cause to be issued, delivered or sold, additional shares of
capital stock or voting securities of the Company or any of its Subsidiaries or
obligating the Company or any of its Subsidiaries to grant, extend or enter into
any such option, warrant, call, right or agreement. Each outstanding share of
capital stock of each Subsidiary of the Company that is a corporation is duly
authorized, validly issued, fully paid and nonassessable and each such share is
owned by the Company or another Subsidiary of the Company, free and clear of all
security interests, liens, claims, pledges, options, rights of first refusal,
agreements, limitations on voting rights, charges and other encumbrances of any
nature whatsoever ("Claims"). With respect to the Grays Ferry Cogeneration
Partnership, which is the only Subsidiary of the Company which is a partnership
(the "Partnership"), CogenAmerica Schuylkill, Inc. has good and valid title to
the partnership interests owned by it in the Partnership, free and clear of all
Claims. There are no outstanding (i) subscriptions or other rights to purchase
or otherwise acquire any partnership interest in the Partnership, (ii)
securities convertible into or exchangeable for any partnership interest in the
Partnership, or (iii) obligations of the Partnership to issue, deliver or sell
any partnership interest, voting securities or securities convertible into or
exchangeable for partnership interests in the Partnership. Except for the
Subsidiaries of the Company disclosed in the Company SEC Documents (as defined
in Section 3.5 below), the Company does not own or control, directly or
indirectly, any capital stock or other securities of, or have any ownership
interest in, any Person. The Company does not have any outstanding bonds,
debentures, notes or other obligations the holders of which have the right to
vote (or convertible into or exercisable for securities having the right to
vote) with the stockholders of the Company on any matter. Exhibit 21 to the
Company's Annual Report on Form 10-K for the year ended December 31, 1998 (the
"Company Annual Report"), as filed with the Securities and Exchange Commission
("SEC"), is a true, accurate and correct statement in all material respects of
all of the information as of December 31, 1998 required to be set forth therein
by the regulations of the SEC.

                  Section 3.3 Authority. On or prior to the date of this
Agreement, the Board of Directors of the Company has approved this Agreement in
accordance with the DGCL, resolved to recommend the adoption of this Agreement
by the Company's stockholders and directed that this Agreement be submitted to
the Company's stockholders for adoption. The Company has all

                                       13
<PAGE>   14
requisite corporate power and authority to enter into each Transaction Document
to which it is a Party and, subject, in the case of the Merger, to approval by
the stockholders of the Company, to consummate the Merger. The execution and
delivery of this Agreement by the Company and the consummation by the Company of
the transactions contemplated hereby have been duly authorized by all necessary
corporate action on the part of the Company, subject to (x) approval of this
Agreement by the stockholders of the Company and (y) the filing of the
Certificate of Merger with the Secretary of State of the State of Delaware. This
Agreement has been duly executed and delivered by the Company and (assuming the
valid authorization, execution and delivery of this Agreement by Parent and Sub
and the validity and binding effect of the Agreement on Parent and Sub)
constitutes the valid and binding obligation of the Company enforceable against
the Company in accordance with its terms, except as the enforceability hereof
may be limited by bankruptcy, insolvency, moratorium or other similar laws
affecting the enforcement of creditors' rights generally and to judicial
limitations on the enforcement of specific performance and other equitable
remedies. The filing of the Proxy Statement with the SEC has been duly
authorized by the Company's Board of Directors.

                  Section 3.4 Consents and Approvals; No Violation. Assuming
that all consents, approvals, authorizations and other actions described in this
Section 3.4 have been obtained and all filings and obligations described in this
Section 3.4 have been made, the execution and delivery of this Agreement does
not, and the consummation of the transactions contemplated hereby and compliance
with the provisions hereof will not, result in any violation of, or default
(with or without notice or lapse of time, or both) under, or give to others a
right of termination, cancellation or acceleration of any obligation or the loss
of a material benefit under, or result in the creation of any Claim upon any of
the properties or assets of the Company or any of its Subsidiaries under, any
provision of (i) the Certificate of Incorporation or By-Laws of the Company,
(ii) any provision of the comparable charter or organization documents of any of
the Company's Subsidiaries, (iii) any loan or credit agreement, note, bond,
mortgage, indenture, lease or other agreement, instrument, permit, concession,
franchise or license applicable to the Company or any of its Subsidiaries or
(iv) any judgment, order, decree, statute, law, ordinance, rule or regulation
applicable to the Company or any of its Subsidiaries or any of their respective
properties or assets, other than, in the case of clauses (ii), (iii) or (iv),
any such violations, defaults, rights, liens, security interests, charges or
encumbrances that, individually or in the aggregate, would not have a Material
Adverse Effect on the Company, materially impair the ability of the Company to
perform its obligations hereunder or prevent the consummation of any of the
transactions contemplated hereby or thereby. No filing or registration with, or
authorization, consent or approval of, any Governmental Entity is required by or
with respect to the Company or any of its Subsidiaries in connection with the
execution and delivery of any Transaction Document to which it is a party or is
necessary for the consummation of the Transactions, except for (i) in
connection, or in compliance, with the provisions of the HSR Act, the Securities
Act and the Exchange Act, (ii) the filing of the Certificate of Merger with the
Secretary of State of the State of Delaware and appropriate documents with the
relevant authorities of other states in which the Company or any of its
Subsidiaries is qualified to do business, (iii) such filings, authorizations,
notices, orders and approvals as may be required to obtain the Regulatory
Approval, the State Takeover Approvals and in connection with the Applicable New
Jersey Laws (collectively, the "Governmental Approvals") and (iv) such other
consents, orders, authorizations, registrations, declarations and filings the
failure of which to be obtained or made would not, individually or in the
aggregate, have a Material Adverse Effect on the Company, or materially impair
the ability of the

                                       14
<PAGE>   15

Company to perform its obligations hereunder or prevent the consummation of any
of the transactions contemplated hereby.

                  Section 3.5  SEC Documents and Other Reports.

                  (a) The Company has filed all required documents with the SEC
since April 30, 1996 pursuant to Sections 13(a) and 15(d) of the Exchange Act
(the "Company SEC Documents"). As of their respective dates, the Company SEC
Documents complied in all material respects with the requirements of the
Securities Act or the Exchange Act, as the case may be, and, at the respective
times they were filed, none of the Company SEC Documents contained any untrue
statement of a material fact or omitted to state a material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading. The consolidated
financial statements (including, in each case, any notes thereto) of the Company
included in the Company SEC Documents (the "Financial Statements") complied as
to form in all material respects with applicable accounting requirements and the
published rules and regulations of the SEC with respect thereto, were prepared
in accordance with generally accepted accounting principles (except, in the case
of the unaudited statements, as permitted by Form 10-Q of the SEC) applied on a
consistent basis during the periods involved (except as may be indicated therein
or in the notes thereto), are in accordance with the books and records of the
Company and fairly presented in all material respects the consolidated financial
position of the Company and its consolidated Subsidiaries as at the respective
dates thereof and the consolidated results of their operations and their
consolidated cash flows for the periods then ended (subject, in the case of
unaudited statements, to normal year-end audit adjustments and to any other
adjustments described therein). Except as disclosed in the Company SEC Documents
or as required by generally accepted accounting principles, the Company has not,
since December 31, 1998, made any change in the accounting practices or policies
applied in the preparation of financial statements. Except as and to the extent
set forth in the Company Annual Report, neither the Company nor any of its
Subsidiaries had as of December 31, 1998 any liabilities or obligations of any
nature, whether or not accrued, contingent or otherwise, that would be required
by generally accepted accounting principles to be reflected on the consolidated
balance sheet of the Company and its Subsidiaries (including the notes thereto)
included in the Financial Statements that are not so reflected.

                  (b) The Company has provided to Parent true and complete
copies of the financial statements for its Subsidiaries described in Section 3.5
of the Company Letter (the "Project Financial Statements"). The Project
Financial Statements have been prepared in accordance with generally accepted
accounting principles applied on a consistent basis during the periods involved
(except as may be indicated therein or in the notes thereto), are in accordance
with the books and records of the relevant Subsidiary, and fairly present, in
all material respects, the financial position of such Subsidiary as at the
respective dates thereof and the results of its operations and its cash flows
for the periods then ended.

                  Section 3.6 Information Supplied. Each document required to be
filed by the Company with the SEC in connection with the transactions
contemplated by this Agreement, including, without limitation, the Proxy
Statement and the Schedule 13e-3, and any amendments or supplements thereto will
comply in all material respects with the provisions of the Exchange Act. Neither
the Proxy Statement (other than with respect to information contained in the
Proxy

                                       15
<PAGE>   16

Statement provided to the Company by Parent for inclusion in the Proxy
Statement) nor any of the information supplied by the Company for inclusion or
incorporation by reference in the Schedule 13e-3, together with any amendments
or supplements thereto, will (i) in the case of the Proxy Statement, at the time
of the mailing of the Proxy Statement and at the time of the Stockholder Meeting
contain any untrue statement of a material fact or omit to state any material
fact required to be stated therein or necessary in order to make the statements
therein, in light of the circumstances under which they are made, not
misleading, and (ii) in the case of information supplied by the Company for
inclusion or incorporation by reference in the Schedule 13e-3, at the time of
its filing, at the time of the dissemination of the Schedule 13e-3 and until the
Effective Time, contain any untrue statement of a material fact or omit to state
any material fact required to be stated therein or necessary in order to make
the statements therein not misleading.

                  Section 3.7 Absence of Certain Changes or Events. Except as
disclosed in the Company SEC Documents filed with the SEC prior to the date of
this Agreement, since December 31, 1998 to the date hereof, (A) the Company and
its Subsidiaries have not incurred any material liability or obligation
(indirect, direct or contingent), or entered into any material oral or written
agreement or other transaction, that is not in the ordinary course of business
or that would result in a Material Adverse Effect on the Company, (B) there has
been no change in the capital stock of the Company except for the issuance of
shares of the Company Common Stock pursuant to the exercise of Company Stock
Options and no dividend or distribution of any kind declared, paid or made by
the Company on any class of its stock, (C) there has not been (x) any granting
by the Company or any of its Subsidiaries to any executive officer of the
Company or any of its Subsidiaries of any increase in compensation, except in
the ordinary course of business consistent with prior practice or as was
required under employment agreements in effect as of the date of the most recent
audited financial statements included in the Company SEC Documents, (y) any
granting by the Company or any of its Subsidiaries to any such executive officer
of any increase in severance or termination agreements in effect as of the date
of the most recent audited financial statements included in the Company SEC
Documents or (z) any entry by the Company or any of its Subsidiaries into any
employment, deferred compensation, severance or termination agreement with any
such executive officer, and (D) there has been no event causing a Material
Adverse Effect on the Company, nor any development that would, individually or
in the aggregate, result in a Material Adverse Effect on the Company.

                  Section 3.8 Permits and Compliance. Each of the Company and
its Subsidiaries is in possession of all franchises, grants, authorizations,
licenses, permits, easements, variances, exceptions, consents, certificates,
approvals and orders of any Governmental Entity necessary for the Company or any
of its Subsidiaries to own, lease and operate its properties or to carry on its
business as it is now being conducted (the "Company Permits"), except where the
failure to have any of the Company Permits would not, individually or in the
aggregate, have a Material Adverse Effect on the Company, and as of the date of
this Agreement no suspension or cancellation of any of the Company Permits is
pending or, to the Knowledge of the Company (as hereinafter defined),
threatened, except where the suspension or cancellation of any of the Company
Permits would not, individually or in the aggregate, have a Material Adverse
Effect on the Company. Neither the Company nor any of its Subsidiaries is in
violation of (A) its Certificate of Incorporation, by-laws or other
organizational documents, (B) any applicable law, ordinance, administrative or
governmental rule or regulation or (C) any order, decree or judgment of any
Governmental Entity having jurisdiction over the Company or any of its
Subsidiaries, except, in the case of clauses (B) and (C), for any violations
that,

                                       16
<PAGE>   17

individually or in the aggregate, would not have a Material Adverse Effect on
the Company. Except as disclosed in the Company SEC Documents filed prior to the
date of this Agreement, as of the date of this Agreement none of the Company or
any of its Subsidiaries is a party to any Material Contract. For purposes of
this Agreement, "Material Contract" shall mean any contract or agreement filed
as an exhibit to the Company SEC Documents or any other contract or agreement
that is material to the business, properties, assets, liabilities, condition
(financial or otherwise) or results of operations of the Company and its
Subsidiaries, taken as a whole. Except as set forth in the Company SEC Documents
filed prior to the date of this Agreement, no event of default or event that,
but for the giving of notice or the lapse of time or both, would constitute an
event of default exists or, upon the consummation by the Company of the
transactions contemplated by this Agreement, will exist under any indenture,
mortgage, loan agreement, note or other agreement or instrument for borrowed
money, any guarantee of any agreement or instrument for borrowed money, or any
lease, contractual license or other agreement or instrument to which the Company
or any of its Subsidiaries is a party or by which the Company or any such
Subsidiary is bound or to which any of the properties, assets or operations of
the Company or any such Subsidiary is subject, other than any defaults that,
individually or in the aggregate, would not have a Material Adverse Effect on
the Company. All Material Contracts (other than the Affiliate Arrangements (as
defined in Section 3.21 below) which will be terminated at the Effective Time)
to which the Company or any of its Subsidiaries is a party are in full force and
effect and are the valid and binding obligations of the Company or the
applicable Subsidiary, enforceable in accordance with their respective terms,
subject to bankruptcy, insolvency, moratorium or other similar laws affecting
the enforcement of creditors' rights generally and to judicial limitations on
the enforcement of specific performance and other equitable remedies. The
Company has made available or delivered to Parent true and complete copies of
the Material Contracts and all other documents referred to in the Company
Letter, in each case as amended to the date of this Agreement. As of the date of
this Agreement, set forth in Section 3.8 of the Company Letter is a description
of any material changes to the amount and terms of the indebtedness of the
Company and its Subsidiaries as described in the Company Annual Report. For
purposes of this Agreement, "Knowledge of the Company" means the actual
knowledge of the executive officers of the Company after due inquiry.

                  Section 3.9 Tax Matters. (i) The Company and each of its
Subsidiaries have timely filed all federal, and all material state, local,
foreign and provincial, Tax Returns required to have been filed or appropriate
extensions therefor have been properly obtained, and such Tax Returns are
correct and complete, except to the extent that any failure to so file or any
failure to be correct and complete would not, individually or in the aggregate,
have a Material Adverse Effect on the Company; (ii) all Taxes shown to be due on
such Tax Returns have been timely paid, taking into account extensions for
payment that have been properly obtained, or such Taxes are being timely and
properly contested which contests as of the date of this Agreement have been
disclosed in Section 3.9 of the Company Letter; (iii) the Company and each of
its Subsidiaries have complied in all material respects with all rules and
regulations relating to the withholding of Taxes except to the extent that any
failure to comply with such rules and regulations would not, individually or in
the aggregate, have a Material Adverse Effect on the Company; (iv) neither the
Company nor any of its Subsidiaries has waived any statute of limitations in
respect of its Taxes; (v) any Tax Returns referred to in clause (i) relating to
federal and state income Taxes have been examined by the IRS or the appropriate
state taxing authority or the period for assessment of the Taxes in respect of
which such Tax Returns were required to be filed has expired; (vi) no material
issues that have been raised


                                       17
<PAGE>   18
in writing by the relevant taxing authority in connection with the examination
of the Tax Returns referred to in clause (i) are currently pending and each such
examination has been completed; (vii) all deficiencies asserted or assessments
made as a result of any examination of such Tax Returns by any taxing authority
have been paid in full or are being timely and properly contested which contests
as of the date of this Agreement have been disclosed in Section 3.9 of the
Company Letter; and (viii) no withholding is required under Section 1445 of the
Code in connection with the Merger; (ix) neither the Company nor any of its
Subsidiaries is party to or bound by any tax-sharing agreement, tax indemnity
obligation or similar agreement, arrangement or practice with respect to Taxes
(including any advance pricing agreement, closing agreement or other agreement
relating to Taxes with any taxing authority); (x) neither the Company nor any of
its Subsidiaries nor any affiliated group that includes any of them shall be
required to include in a taxable period ending after the Closing Date any
material amount of taxable income attributable to income that accrued in a prior
taxable period but was not recognized in any prior taxable period as a result of
the installment method of accounting, the long-term contract method of
accounting, the cash method of accounting or Section 481 of the Code or any
comparable provision of state, local, or foreign Tax law, or for any other
reason; (xi) neither the Company nor any of its Subsidiaries has made any
consent under Section 341 of the Code, no property of the Company or of any of
its Subsidiaries is "tax exempt use property" within the meaning of Section
168(h) of the Code, neither the Company nor any of its Subsidiaries is a party
to any lease made pursuant to Section 168(f)(8) of the Internal Revenue Code of
1954 and none of the assets of the Company or of any of its Subsidiaries is
subject to a lease under Section 7701(h) of the Code or under any predecessor
section thereof; (xii) neither the Company nor any of its Subsidiaries has
requested any extension of time within which to file any Tax return, which
return has not yet been filed; and (xiii) no power of attorney with respect to
any Taxes has been executed or filed with any taxing authority by or on behalf
of the Company or any of its Subsidiaries. The Company has delivered or made
available to Parent for inspection (A) true and complete copies of all material
Tax returns of the Company and any affiliated group of which the Company is a
member and of any of the Company's Subsidiaries relating to Taxes for all
taxable periods for which the applicable statute of limitations has not yet
expired and (B) complete and correct copies of all material private letter
rulings, revenue agent reports, information document requests, notices of
proposed deficiencies, deficiency notices, protests, petitions, closing
agreements, settlement agreements, pending ruling requests and any similar
documents, submitted by, received by or agreed to by or on behalf of the Company
or any such group or Subsidiary, or, to the extent related to the income,
business, assets, operations, activities or status of the Company or any such
group or Subsidiary, submitted by, received by or agreed to by or on behalf of
any affiliated group of which the Company is or has ever been a member, and
relating to Taxes for all taxable periods for which the statute of limitations
has not yet expired. No material liens exist for Taxes (other than liens for
Taxes not yet due and payable) with respect to any of the assets or properties
of the Company or any of its Subsidiaries. The Federal income Tax returns of the
Company and its Subsidiaries and any affiliated group that includes any of them
have expressly disclosed any Tax positions of the Company, such Subsidiaries or
such group that, if not disclosed, could give rise to material penalties under
Section 6662 of the Code. For purposes of this Agreement: (i) "Taxes" means any
federal, state, local, foreign or provincial income, gross receipts, property,
sales, use, license, excise, franchise, employment, payroll, withholding,
alternative or added minimum, ad valorem, value-added, transfer or excise tax,
or other tax, custom, duty, governmental fee or other like assessment or charge
of any kind whatsoever, together with any interest or penalty imposed by any
Governmental Entity, and (ii) "Tax Return" means any return, report or similar
statement


                                       18
<PAGE>   19
(including the attached schedules) required to be filed with respect to any Tax,
including, without limitation, any information return, claim for refund, amended
return or declaration of estimated Tax.

                  Section 3.10 Actions and Proceedings. Except as set forth in
the Company SEC Documents filed prior to the date of this Agreement, there are,
as of the date of this Agreement, no outstanding orders, judgments, injunctions,
awards or decrees of any Governmental Entity against or involving (i) the
Company or any of its Subsidiaries, (ii) to the Knowledge of the Company, any of
the present or former directors, officers, employees, consultants, agents or
stockholders of the Company or any of its Subsidiaries, as such, (iii) any of
the properties, assets or businesses of the Company or any of its Subsidiaries
or (iv) any Company Plan (as hereinafter defined) that, individually or in the
aggregate, would have a Material Adverse Effect on the Company or materially
impair the ability of the Company to perform its obligations hereunder. As of
the date of this Agreement, there are no actions, suits or claims or legal,
administrative or arbitrative proceedings or investigations pending or, to the
Knowledge of the Company, threatened against or involving (i) the Company or any
of its Subsidiaries, (ii) to the Knowledge of the Company, any of its or their
present or former directors, officers, employees, consultants, agents or
stockholders, as such, (iii) any of the properties, assets or businesses of the
Company or any of its Subsidiaries or (iv) any Company Plan (as hereinafter
defined) that, individually or in the aggregate, would have a Material Adverse
Effect on the Company or materially impair the ability of the Company to perform
its obligations hereunder. As of the date hereof, there are no actions, suits,
labor disputes or other litigation, legal or administrative proceedings or
governmental investigations pending or, to the Knowledge of the Company,
threatened against or affecting (i) the Company or any of its Subsidiaries, (ii)
to the Knowledge of the Company, any of its or their present or former officers,
directors, employees, consultants, agents or stockholders, as such, (iii) any of
the properties, assets or businesses of the Company or any of its Subsidiaries
or (iv) any Company Plan, in each case relating to the transactions contemplated
by this Agreement. The Company is not in default with respect to any material
final judgment, order or decree of any court or any governmental agency or
instrumentality.

                  Section 3.11 Certain Agreements. Except as set forth in
Section 3.11 of the Company Letter or as provided pursuant to Section 1.7(d)
hereof, neither the Company nor any of its Subsidiaries is a party to any oral
or written agreement or plan, including any employment agreement, severance
agreement, stock option plan, stock appreciation rights plan, restricted stock
plan or stock purchase plan, any of the benefits of which will be increased, or
the vesting of the benefits of which will be accelerated, by the occurrence of
any of the transactions contemplated by this Agreement or the value of any of
the benefits of which will be calculated on the basis of any of the transactions
contemplated by this Agreement. No holder of any option to purchase shares of
Company Common Stock, or shares of Company Common Stock granted in connection
with the performance of services for the Company or its Subsidiaries, is or will
be entitled to receive cash from the Company or any Subsidiary in lieu of or in
exchange for such option or shares as a result of the transactions contemplated
by this Agreement, other than as provided in Section 1.5(d).

                  Section 3.12 ERISA

                  (a) Company Plans. Each Company Plan (as hereinafter defined)
is listed in Section 3.12(a) of the Company Letter. Except as would not have a
Material Adverse Effect on the


                                       19
<PAGE>   20
Company, each Company Plan complies in all respects with the Employee Retirement
Income Security Act of 1974, as amended ("ERISA"), the Code and all other
applicable statutes and governmental rules and regulations, and (i) no
"reportable event" (within the meaning of Section 4043 of ERISA) has occurred
with respect to any Company Plan that is likely to have individually or in the
aggregate, a Material Adverse Effect on the Company, and (ii) no action has been
taken, or is currently being considered, to terminate any Company Plan subject
to Title IV of ERISA. No Company Plan, nor any trust created thereunder, has
incurred any "accumulated funding deficiency" (as defined in Section 412 of the
Code or Section 302 of ERISA), whether or not waived.

                  (b) Plan Liabilities. With respect to the Company Plans, no
event has occurred and, to the Knowledge of the Company, there exists no
condition or set of circumstances in connection with which the Company or any
ERISA Affiliate or Company Plan fiduciary could be subject to any liability
under the terms of such Company Plans, ERISA, the Code or any other applicable
law, other than liabilities for benefits payable in the normal course, which
would have a Material Adverse Effect on the Company. All Company Plans that are
intended to be qualified under Section 401(a) of the Code have been determined
by the IRS to be so qualified, or a timely application for such determination is
now pending or a request for such a determination filed within the remedial
amendment period of Section 401(b) of the Code is pending, and the Company is
not aware of any reason why any such Company Plan is not so qualified in
operation. Neither the Company nor any entity which is treated as a single
employer along with the Company under Section 414(b), (c), (m) or (o) of the
Code maintains or contributes to, or has ever maintained or contributed to, or
been required to contribute to or has otherwise incurred any liability with
respect to a "multiemployer plan" within the meaning of Section 3(37) of ERISA
or any plan subject to Title IV of ERISA. Except as disclosed in Section 3.12(b)
of the Company Letter, neither the Company nor any of its ERISA Affiliates has
any liability or obligation under any welfare plan to provide benefits after
termination of employment to any employee or dependent other than as required by
Section 4980B of the Code.

                  (c) Definitions. As used herein, (i) "Company Plan" means a
"pension plan" (as defined in Section 3(2) of ERISA), a "welfare plan" (as
defined in Section 3(1) of ERISA), or any bonus, profit sharing, deferred
compensation, incentive compensation, stock ownership, stock purchase, stock
option, phantom stock, holiday pay, vacation, severance, death benefit, sick
leave, fringe benefit, personnel policy, insurance or other plan, arrangement or
understanding, in each case established or maintained by the Company or any of
its ERISA Affiliates or as to which the Company or any of its ERISA Affiliates
has contributed or otherwise may have any liability, and (iii) "ERISA Affiliate"
means any corporation or trade or business controlled by, controlling or under
common control with the Company within the meaning of Section 414 of the Code or
Section 4001(a)(14) or 4001(b) of ERISA.

                  (d) Employment Agreements. Section 3.12(d) of the Company
Letter contains a true and complete list of all (i) severance and employment
agreements with the current and former directors, officers, employees,
independent contractors and consultants of the Company and each ERISA Affiliate
containing any obligation or liability on or after the date of this Agreement,
(ii) severance programs and policies of the Company and each ERISA Affiliate
with or relating to its current and former directors, officers, employees,
independent contractors and consultants containing any obligation or liability
on or after the date of this Agreement, and (iii) plans,


                                       20
<PAGE>   21
programs, agreements and other arrangements of the Company and each ERISA
Affiliate with or relating to its current and former directors, officers,
employees, independent contractors and consultants containing change of control,
acceleration of the time of payment or vesting of benefits or similar provisions
currently in effect (collectively, the "Employee Agreements").

                  Section 3.13 Compliance with Worker Safety and Environmental
Laws. The properties, assets and operations of the Company and its Subsidiaries
are in compliance with all applicable federal, state, local and foreign laws,
rules and regulations, orders, decrees, judgments, permits and licenses relating
to public and worker health and safety (collectively, "Worker Safety Laws") and
the protection and clean-up of the environment and activities or conditions
related thereto, including, without limitation, those relating to the
generation, handling, disposal, transportation or release of hazardous materials
(collectively, "Environmental Laws"), except for any violations that,
individually or in the aggregate, would not have a Material Adverse Effect on
the Company. With respect to such properties, assets and operations, including
any previously owned, leased or operated properties, assets or operations, there
are no events, conditions, circumstances, activities, practices, incidents,
actions or plans of the Company or any of its Subsidiaries that may interfere
with or prevent compliance or continued compliance with applicable Worker Safety
Laws and Environmental Laws, other than any such interference or prevention as
would not, individually or in the aggregate with any such other interference or
prevention, have a Material Adverse Effect on the Company. None of the Company
or any of its Subsidiaries has received or is aware of any claim or notice of
violations of any applicable Environmental Laws or Worker Safety Laws other than
such claims or violations as would not individually or in the aggregate have a
Material Adverse Effect on the Company.

                  Section 3.14 Labor Matters. Neither the Company nor any of its
Subsidiaries is a party to any collective bargaining agreement or labor
contract. Neither the Company nor any of its Subsidiaries has engaged in any
unfair labor practice with respect to any Persons employed by or otherwise
performing services primarily for the Company or any of its Subsidiaries (the
"Company Business Personnel"), and there is no unfair labor practice complaint
or grievance against the Company or any of its Subsidiaries by the National
Labor Relations Board or any comparable state agency pending or threatened in
writing with respect to the Company Business Personnel, except where such unfair
labor practice, complaint or grievance would not have a Material Adverse Effect
on the Company. There is no labor strike, dispute, slowdown or stoppage pending
or, to the Knowledge of the Company, threatened against or affecting the Company
or any of its Subsidiaries which may interfere with the respective business
activities of the Company or any of its Subsidiaries, except where such dispute,
strike or work stoppage would not have a Material Adverse Effect on the Company.

                  Section 3.15 State Takeover Statute. Section 203 of the DGCL
is not applicable to the Transactions.

                  Section 3.16 Required Vote of Company Stockholders. The
affirmative vote of the holders of two-thirds of the outstanding shares of
Company Common Stock is required to approve the Merger. No other vote of the
security holders of the Company is required by law, the Certificate of
Incorporation or By-laws of the Company or otherwise in order for the Company to
consummate the Transactions.



                                       21
<PAGE>   22
                  Section 3.17 Brokers. No broker, investment banker or other
Person, other than Donaldson, Lufkin & Jenrette Securities Corporation (the
"Financial Advisor"), is entitled to any broker's, finder's or other similar fee
or commission in connection with the transactions contemplated by this Agreement
based upon arrangements made by or on behalf of the Company. The Company has
furnished Parent a true and correct copy of the engagement agreement with the
Financial Advisor.

                  Section 3.18 Opinion of Financial Advisor. The Company has
received the opinion of the Financial Advisor addressed to the Company's Board
of Directors, dated the date of this Agreement, to the effect that, as of such
date, the consideration to be received in the Merger by the holders of the
shares of Company Common Stock is fair from a financial point of view to the
Company's stockholders, other than NRG Energy, Inc. A signed copy of such
opinion has been delivered to Parent.

                  Section 3.19 Utility Regulation. None of the Company or any of
its Subsidiaries is (i) subject to regulation under the Public Utility Holding
Company Act of 1935 ("PUHCA") (other than any such regulation contemplated by
Section 9(a)(2), 32 or 33 of PUHCA), (ii) subject to regulation as an "electric
utility" or a "public utility" as such terms are defined in the Federal Power
Act (other than as contemplated by 18 C.F.R. Section 292.601(c) or Section 32 or
33 of PUHCA), or (iii) subject to regulation by any state respecting the rates
of electric utilities or the financial and organizational regulation of electric
utilities as those terms are used in Section 210(e) of the Public Utility
Regulatory Policies Act of 1978 ("PURPA"), except with respect to participation
in, or ownership of, an "exempt wholesale generator" as such term is defined in
Section 32 of PUHCA. Not more than 50% of the ultimate ownership of the projects
operated by the Subsidiaries is held by Persons primarily engaged in the
generation or sale of electric power (other than electric power solely from
qualifying cogeneration facilities, qualifying small power production
facilities, exempt wholesale generators or foreign utilities companies (as
defined in Section 33 of PUHCA)) within the meaning of the Federal Power Act.
Each such project has self-certified itself to be in compliance with such
requirements without objection by FERC or FERC has issued a final order stating
that each such project is a facility which complies with the definition of
"cogeneration facility" as set forth in 18 C.F.R. Section 292.202(c) and which
meets all of the requirements for qualification set forth in 18 C.F.R. Section
292.203(b).

                  Section 3.20 Insurance. Section 3.20 of the Company Letter
contains a true and complete list of all material insurance policies held by the
Company or any of its Subsidiaries. All such policies are in full force and
effect and all related premiums have been paid to date. As of the date of this
Agreement, there are no pending or, to the Knowledge of the Company, threatened
disputes or communications with or from any insurance carrier denying or
disputing any claim or regarding cancellation or non-renewal of any such policy
which if determined adversely to the Company, would have a Material Adverse
Effect on the Company.

                  Section 3.21 Related Party Transactions. No director or
officer of the Company or any of its Subsidiaries or any Person which as of the
date of this Agreement has a Schedule 13D or 13G on file with the Securities and
Exchange Commission with respect to the Company Common Stock (each such Person,
a "Significant Holder"), or any member of the immediate family of any


                                       22
<PAGE>   23
such director, officer, Significant Holder or any Person in which any such
director, officer, Significant Holder, or any member of the immediate family of
any such director or officer, is an officer, director, trustee, partner or
holder of more than 50% of the outstanding capital stock or equity interests, is
a party to any material executory transaction with the Company or any of its
Subsidiaries. There are not loans, guarantees, letters of credit or other forms
of credit support provided by or on behalf of any director or officer of the
Company or any of its Subsidiaries to or in favor of the Company or any of its
Subsidiaries. For purposes of this Agreement, "Affiliate Arrangements" shall
mean the arrangements identified on Section 3.21 of the Company Letter that will
terminate at the Effective Time.


                                   ARTICLE IV

                            COVENANTS OF THE COMPANY

                  Section 4.1 Conduct of Business Pending the Merger. Except as
expressly permitted by clauses (i) through (xvi) of this Section 4.1 or as set
forth in the Company Letter, during the period from the date of this Agreement
through the Effective Time, the Company shall, and shall cause each of its
Subsidiaries to carry on its business in the ordinary course of its business as
currently conducted and, to the extent consistent therewith, use best efforts to
preserve intact its current business organizations, keep available the services
of its current officers and employees and preserve its relationships with
customers, suppliers and others having business dealings with it to the end that
its goodwill and ongoing business shall be unimpaired at the Effective Time.
Without limiting the generality of the foregoing, and except as otherwise
expressly contemplated by this Agreement or as set forth in the Company Letter,
the Company shall not, and shall not permit any of its Subsidiaries to, without
the prior written consent of Parent (which consent shall not be unreasonably
withheld or delayed):

                  (i) (A) declare, set aside or pay any dividends on, or make
         any other actual, constructive or deemed distributions in respect of,
         any of its capital stock, or otherwise make any payments to its
         stockholders in their capacity as such (other than dividends and other
         distributions by Subsidiaries), (B) split, combine or reclassify any of
         its capital stock or issue or authorize the issuance of any other
         securities in respect of, in lieu of or in substitution for shares of
         its capital stock or (C) purchase, redeem or otherwise acquire any
         shares of capital stock of the Company or any of its Subsidiaries or
         any other interests or securities thereof or any rights, warrants or
         options to acquire any such shares or other interests or securities;

                  (ii) issue, deliver, sell, pledge, dispose of or otherwise
         encumber any shares of its capital stock or partnership interests, any
         other voting securities or equity equivalent or any securities
         convertible into, or any rights, warrants or options to acquire any
         such shares or interests, voting securities, equity equivalent or
         convertible securities, other than the issuance of shares of Company
         Common Stock upon the exercise of Company Stock Options outstanding on
         the date of this Agreement in accordance with their current terms.

                  (iii) amend its Certificate of Incorporation or charter or
         By-Laws;



                                       23
<PAGE>   24
                  (iv) acquire or agree to acquire by merging or consolidating
         with, or by purchasing a substantial portion of the assets of or equity
         in, or by any other manner, any business or any corporation, limited
         liability company, partnership, association or other business
         organization or division thereof or otherwise acquire or agree to
         acquire any assets, other than transactions that are in the ordinary
         course of business consistent with past practice and that have a
         transaction value less than $250,000 individually or $1,000,000 in the
         aggregate and not material to the Company and its Subsidiaries taken as
         a whole;

                  (v) sell, lease or otherwise dispose of, or agree to sell,
         lease or otherwise dispose of, any of its assets, other than
         transactions that are in the ordinary course of business consistent
         with past practice and that have a transaction value less than $250,000
         individually or $1,000,000 in the aggregate;

                  (vi) incur any indebtedness for borrowed money, guarantee any
         such indebtedness or make any loans, advances or capital contributions
         to, or other investments in, any other Person, other than (A) any such
         obligations incurred in the ordinary course of business consistent with
         past practices and that are less than $500,000 in the aggregate, and
         (B) indebtedness, loans, advances, capital contributions and
         investments between the Company and any of its Subsidiaries or between
         any of such Subsidiaries;

                  (vii) alter (through merger, liquidation, reorganization,
         restructuring or in any other fashion) the corporate structure or
         ownership of the Company or of any of its Subsidiaries;

                  (viii) enter into or adopt any, or amend any existing,
         severance plan, agreement or arrangement or enter into or amend any
         Company Plan or employment or consulting agreement, except in the case
         of any amendments to any Company Plan, for any immaterial changes as
         required by applicable law;

                  (ix) increase the compensation payable or to become payable to
         its current or former directors, officers, employees, independent
         contractors or consultants or grant any severance or termination pay
         to, or enter into or amend any employment or severance agreement with,
         any current or former director, officer, employee, independent
         contractor or consultant of the Company or any of its Subsidiaries, or
         establish, adopt, enter into, or, except in the case of any amendments
         to any Company Plan, for any immaterial changes as may be required to
         comply with applicable law, amend in any material respect or take
         action to enhance in any material respect or accelerate the payment or
         vesting of any rights or benefits under, any labor, collective
         bargaining, bonus, profit sharing, thrift, compensation, stock option,
         restricted stock, pension, retirement, deferred compensation,
         employment, termination, severance or other plan, agreement, trust,
         fund, policy or arrangement for the benefit of any director, officer,
         employee, consultant or independent contractor;

                  (x) violate or fail to perform any obligation or duty imposed
         upon it or any of its Subsidiaries by any applicable material federal,
         state or local law, rule, regulation, guideline or ordinance;



                                       24
<PAGE>   25
                  (xi) make any change to accounting policies or procedures
         (other than actions required to be taken by generally accepted
         accounting principles);

                  (xii) prepare or file any Tax Return inconsistent with past
         practice or, on any such Tax Return, take any position, make any
         election, or adopt any method that is inconsistent with positions
         taken, elections made or methods used in preparing or filing similar
         Tax Returns in prior periods;

                  (xiii) make any tax election or settle or compromise any
         material federal, state, local or foreign income tax liability;

                  (xiv) enter into any contract which involves aggregate
         payments in excess of $250,000 for individual contracts or $1,000,000
         in the aggregate for all contracts or amend, terminate, renew or waive
         any rights of material value under, any Material Contract of the
         Company or any of its Subsidiaries; or other than as described in
         Section 4.1(xiv) of the Company Letter, make or agree to make any new
         capital expenditure or expenditures in excess of $250,000 individually
         or $500,000 in the aggregate;

                  (xv) pay, discharge or satisfy any claims, liabilities or
         obligations (absolute, accrued, asserted or unasserted, contingent or
         otherwise), other than (a) the payment, discharge or satisfaction, in
         the ordinary course of business consistent with past practice or in
         accordance with their terms, of liabilities reflected or reserved
         against in, or contemplated by, the most recent financial statements
         (or the notes thereto) of the Company included in the Company SEC
         Documents or incurred in the ordinary course of business consistent
         with past practice or (b) payments of principal and interest and
         related fees on indebtedness owed by the Company or any of its
         Subsidiaries under existing revolving credit facilities and scheduled
         payments of principal and interest and related fees on any other
         indebtedness owed by the Company or any of its Subsidiaries under any
         existing credit facility;

                  (xvi) take any write-down of the value of any asset or take
         any write-off as uncollectible of any accounts or notes receivable or
         any portion thereof, except to the extent such write-down or write-off
         is required by generally accepted accounting principles or is
         consistent with the historic accounting policies adhered to by the
         Company or its Subsidiaries, as applicable; or

                  (xvii) authorize, recommend, propose or announce an intention
         to do any of the foregoing, or enter into any contract, agreement,
         commitment or arrangement to do any of the foregoing.

                  Section 4.2 No Solicitation.

                  (a) Takeover Proposals. The Company shall not, nor shall it
permit any of its Subsidiaries to, nor shall it authorize or permit any officer,
director or employee of or any financial advisor, attorney or other advisor or
representative of, the Company or any of its Subsidiaries to, (i) solicit,
initiate or encourage the submission of, any Takeover Proposal (as hereafter
defined), (ii) enter into any agreement with respect to any Takeover Proposal or
(iii) participate in any discussions


                                       25
<PAGE>   26
or negotiations regarding, or furnish to any Person any information with respect
to, or take any other action to facilitate any inquiries or the making of any
proposal that constitutes, or may reasonably be expected to lead to, any
Takeover Proposal; provided, however, that, if the Board of Directors of the
Company reasonably determines the Takeover Proposal constitutes a Superior
Proposal (as defined below), then, to the extent required by the fiduciary
obligations of the Board of Directors of the Company, as determined in good
faith by a majority of the disinterested members thereof after receiving the
advice of independent legal counsel, the Company may, in response to an
unsolicited request therefor, furnish information with respect to the Company
to, and enter into discussions with, any Person that has made such Takeover
Proposal pursuant to a customary confidentiality agreement. For purposes of this
Agreement, (i) "Takeover Proposal" means any proposal for, offer or indication
of interest in a merger or other business combination involving the Company or
any of its Subsidiaries or any proposal or offer to acquire in any manner,
directly or indirectly, a substantial equity interest in, a substantial portion
of the voting securities of, or a substantial portion of the assets of the
Company or any of its Subsidiaries, other than the transactions contemplated by
this Agreement, and (ii) "Superior Proposal" means a bona fide Takeover Proposal
made by a third party which a majority of the disinterested members of the Board
of Directors of the Company determines in its reasonable good faith judgment to
be more favorable to the Company's stockholders than the Merger (after receiving
the opinion, with only customary qualifications, of the Company's independent
financial advisor of nationally recognized reputation that the value of the
consideration provided for in such proposal exceeds the value of the
consideration provided for in the Merger) and for which financing, to the extent
required, is then committed or which, in the reasonable good faith judgment of a
majority of such disinterested members (after receiving the advice of the
Company's independent financial advisor), is highly likely to be financed by
such third party.

                  (b) Recommendation of the Board of Directors. Except as
expressly permitted by this Section 4.2, neither the Board of Directors of the
Company nor any committee thereof shall (i) withdraw or modify, or propose to
withdraw or modify, in a manner adverse to Parent or Sub, the approval or
recommendation by such Board of Directors or any such committee of the Merger or
(ii) approve or recommend, propose to approve or recommend, or cause the Company
to enter into any letter of intent, agreement in principle or legally binding
acquisition agreement (the "Company Acquisition Agreement") relating to any
Takeover Proposal. Notwithstanding the foregoing, if the Company has received a
Superior Proposal, the Board of Directors of the Company may (subject to this
and the following sentences) terminate this Agreement, but only at a time that
is more than four (4) business days following Parent's receipt of written notice
advising Parent that the Company's Board of Directors is prepared to accept such
Superior Proposal, specifying the material terms and conditions of such Superior
Proposal and identifying the Person making such Superior Proposal; provided,
however, that (x) at the time of such termination, such proposal continues to be
a Superior Proposal, taking into account any amendment of the terms of the
Merger by Parent or any proposal by Parent to amend the terms of this Agreement,
the Merger or any other Takeover Proposal made by Parent (a "New Parent
Proposal"), and (y) concurrently with or immediately after such termination, the
Company's Board of Directors shall cause the Company to enter into a definitive
agreement with respect to such Superior Proposal.

                  (c) Notice of Takeover Proposal. The Company shall advise
Parent orally (within one business day) and in writing (as promptly as
practicable) of (i) any Takeover Proposal or any inquiry with respect to or
which could lead to any Takeover Proposal, (ii) the material terms of


                                       26
<PAGE>   27
such Takeover Proposal and (iii) the identity of the Person making any such
Takeover Proposal or inquiry. The Company will keep Parent fully informed of the
status and details of any such Takeover Proposal or inquiry.

                  (d) Permitted Actions or Disclosures by the Company. Nothing
contained in this Section 4.2 shall prohibit the Company from taking and
disclosing to its stockholders a position contemplated by Rule 14e-2(a)
promulgated under the Exchange Act or from making any disclosure to the
Company's stockholders if, in the good faith judgment of the Board of Directors
of the Company, after consultation with independent counsel, failure so to
disclose would be inconsistent with its obligations under applicable law;
provided, however, that, except as expressly provided in this Section 4.2,
neither the Company nor its Board nor any committee thereof shall withdraw or
modify, or propose publicly to withdraw or modify, its position with respect to
this Agreement or in connection with the Merger, or approve or recommend, or
propose publicly to approve or recommend, a Takeover Proposal.


                                    ARTICLE V

                              ADDITIONAL AGREEMENTS

                  Section 5.1 Stockholder Meeting. The Company will, as soon as
practicable following the date of this Agreement, duly call, give notice of,
convene and hold a stockholder meeting (the "Stockholder Meeting") for the
purpose of considering the approval of this Agreement and the transactions
contemplated hereby. The Company has, through its Board of Directors,
recommended to its stockholders the adoption or approval of this Agreement, the
Merger and the Amendment, shall use all reasonable efforts to solicit such
approvals by its stockholders and shall not withdraw such recommendation.
Without limiting the generality of the foregoing, the Company agrees that its
obligations pursuant to the first sentence of this Section 5.1 shall not be
affected by the commencement, public proposal, public disclosure or
communication to the Company of a Takeover Proposal.

                  Section 5.2 Preparation of the Proxy Statement and Schedule
13e-3. The Company shall promptly prepare and, after consultation with Parent,
file with the SEC the Proxy Statement and shall use its reasonable best efforts
to obtain and furnish the information required to be included in the Proxy
Statement and, after consultation with Parent, respond promptly to any comments
made by the SEC. In connection with the Company consulting with Parent
concerning the Proxy Statement, the Company shall provide Parent a reasonable
opportunity to review and comment on the Proxy Statement and amendment or
modification thereto prior to filing with the SEC, shall reasonably consider the
comments and suggestions of Parent, shall not change without Parent's consent
any information provided by Parent for inclusion in the Proxy Statement that the
Company requests of Parent, shall promptly notify Parent of the receipt of any
comments or other communications from the SEC regarding the Proxy Statement and
shall provide Parent a reasonable opportunity to review and comment on any
response by the Company to any comments or other communications from the SEC
that requires a response. The Company shall mail the Proxy Statement to its
stockholders at the earliest practical date. Parent, Sub and (to the extent
required by law) their respective affiliates shall promptly prepare and file,
concurrent with the filing of the Proxy


                                       27
<PAGE>   28
Statement and after consultation with the Company, with the SEC the Schedule
13e-3 and the Company shall reasonably cooperate with Parent in connection with
the preparation of the Schedule 13e-3. If at any time prior to the Effective
Time any event with respect to Parent, its officers and directors or Sub shall
occur, which is required to be described in the Schedule 13e-3 or the Proxy
Statement, such event shall be so described, and, in the case of the Schedule
13e-3, Parent will promptly give notice of such event to the Company and an
appropriate amendment or supplement shall be promptly filed with the SEC and, as
required by law, disseminated to the stockholders of the Company. If at any time
prior to the Effective Time any event with respect to the Company, its officers
and directors or any of its Subsidiaries shall occur which is required at that
time to be described in the Proxy Statement or the Schedule 13e-3, such event
shall be so described, and, in the case of the Proxy Statement, the Company
shall promptly notify Parent of such event and an appropriate amendment or
supplement shall be promptly filed with the SEC and, as required by law,
disseminated to the stockholders of the Company.

                  Section 5.3 Access to Information. Subject to currently
existing contractual and legal restrictions applicable to the Company or any of
its Subsidiaries, the Company shall, and shall cause each of its Subsidiaries
to, afford to the accountants, counsel, financial advisors and other
representatives of Parent hereto reasonable access to, and permit them to make
such inspections as they may reasonably require of, during normal business hours
during the period from the date of this Agreement through the Effective Time,
all their respective properties, books, contracts, commitments and records
(including, without limitation, the work papers of independent accountants, if
available and subject to the consent of such independent accountants) and,
during such period, the Company shall, and shall cause each of its Subsidiaries
to, furnish promptly to Parent (i) a copy of each report, schedule, registration
statement and other document filed by it during such period pursuant to the
requirements of federal or state securities laws and (ii) all other information
concerning its business, properties and personnel as Parent may reasonably
request. No investigation pursuant to this Section 5.3 shall affect any
representation or warranty in this Agreement of any party hereto or any
condition to the obligations of the parties hereto. All information obtained by
Parent pursuant to this Section 5.3 shall be kept confidential in accordance
with the Confidentiality Agreement, dated May 17, 1999, between Parent and the
Company (the "Confidentiality Agreement").

                  Section 5.4 Fees and Expenses.

                  (a) Expenses. Except as provided below, all fees and expenses
incurred in connection with the Transactions shall be paid by the party
incurring such fees or expenses, whether or not the Merger is consummated.

                  (b) Termination Fee. The Company shall pay to Parent a
termination fee of $7,500,000 if:

                  (i) the Company terminates this Agreement pursuant to Section
         7.1(d);

                  (ii) (A) after the date of this Agreement and prior to the
         termination of this Agreement, any Person makes a Takeover Proposal,
         (B) this Agreement is terminated pursuant to Section 7.1(b)(iii) or (c)
         and (C) within 12 months of the date of termination of


                                       28
<PAGE>   29
         this Agreement, the Company executes a legally binding definitive
         agreement or an agreement in principle pursuant to which any Person,
         entity or group (other than Parent, Sub or any of their affiliates), in
         one transaction or a series of transactions, will acquire more than 50%
         of the outstanding Company Common Stock or assets of the Company
         through any open market purchases, merger, consolidation, tender or
         exchange offer, recapitalization, reorganization or other business
         combination and such transaction or series of transactions have been
         consummated (an "Third Party Acquisition Event"); or

                  (iii) (A) after the date of this Agreement and prior to the
         termination of this Agreement, any Person makes a Takeover Proposal,
         (B) this Agreement is terminated by Parent pursuant to Section 7.1(e)
         or (f), and (C) a Third Party Acquisition Event occurs within 12 months
         of the date of termination of this Agreement.

Any termination fee due under this Section 5.4(b) shall be paid by wire transfer
of same-day funds on the date of termination of this Agreement in the case of a
fee due under clause (i) of the preceding sentence, or on the date such Third
Party Acquisition Event is consummated in the case of a fee due under clause
(ii) or (iii) of the preceding sentence. The payment of the termination fee
pursuant to this Section 5.4(b) shall constitute liquidated damages and shall be
the sole and exclusive remedy of Parent and Sub if this Agreement is terminated
under the circumstances described above in this Section 5.4(b).

                  Section 5.5 Best Efforts.

                  (a) Consummation of the Merger. Upon the terms and subject to
the conditions set forth in this Agreement, each of the parties agrees to use
best efforts to take, or cause to be taken, all actions, and to do, or cause to
be done, and to assist and cooperate with the other parties in doing, all things
necessary, proper or advisable to consummate and make effective, in the most
expeditious manner practicable, the transactions contemplated by this Agreement,
including, but not limited to: (i) the obtaining of all necessary actions or
non-actions, waivers, consents and approvals from all Governmental Entities and
the making of all necessary registrations and filings (including filings with
Governmental Entities) and the taking of all reasonable steps as may be
necessary to obtain an approval or waiver from, or to avoid an action or
proceeding by, any Governmental Entity (including those in connection with the
HSR Act, the Regulatory Approval, the Applicable New Jersey Laws, and State
Takeover Approvals), (ii) the defending of any lawsuits or other legal
proceedings, whether judicial or administrative, challenging this Agreement and
the consummation of the transactions contemplated hereby, including seeking to
have any stay or temporary restraining order entered by any court or other
Governmental Entity vacated or reversed, (iii) the taking of all reasonable
actions to minimize the effects of any State Takeover Approval on the
transactions contemplated hereby, and (iv) the execution and delivery of any
additional instruments necessary to consummate the transactions contemplated by
this Agreement. No party to this Agreement shall consent to any voluntary delay
of the consummation of the Merger at the behest of any Governmental Entity
without the consent of the other parties to this Agreement, which consent shall
not be unreasonably withheld.

                  (b) Representations and Warranties. Each party shall not take
any action, or enter into any transaction, which would cause any of its
representations or warranties contained in


                                       29
<PAGE>   30
this Agreement to be untrue or result in a breach of any covenant made by it in
this Agreement.

                  (c) Divestiture. Notwithstanding anything to the contrary
contained in this Agreement, in connection with any filing or submission
required or action to be taken by either Parent or the Company to effect the
Merger and to consummate the other transactions contemplated hereby, the Company
shall not, without Parent's prior written consent, commit to any divestiture
transaction, and neither Parent nor any of its Affiliates shall be required to
divest or hold separate or otherwise take or commit to take any action that
limits its freedom of action with respect to, or its ability to retain, the
Company or any of the material businesses, product lines or assets of Parent or
any of its Subsidiaries or that otherwise would have a Material Adverse Effect
on Parent.

                  (d) Company Stock Option Termination Notices. At least sixty
(60) days prior to the Effective Time, the Company will give the "Acceleration
Notice" as defined in and contemplated by the Company Plans pursuant to which
Company Stock Options were granted, provided that the holders of the Company
Stock Options shall be entitled to the Option Consideration pursuant to Section
1.5(d) if such holder executes and delivers the option termination agreement as
contemplated by Section 1.5(d) above.

                  Section 5.6 Public Announcements. Parent and the Company will
not issue any press release with respect to the transactions contemplated by
this Agreement or otherwise issue any written public statements with respect to
such transactions without prior consultation with the other party, except as may
be required by applicable law or by obligations pursuant to any listing
agreement with any national securities exchange or the Nasdaq National Market.

                  Section 5.7 Real Estate Transfer and Gains Tax. Parent and the
Company agree that either the Company or the Surviving Corporation will pay any
state or local tax which is attributable to the transfer of the beneficial
ownership of the Company's or its Subsidiaries' real property, if any
(collectively, the "Gains Taxes"), and any penalties or interest with respect to
the Gains Taxes, payable in connection with the consummation of the Merger. The
Company and Parent agree to cooperate with the other in the filing of any
returns with respect to the Gains Taxes, including supplying in a timely manner
a complete list of all real property interests held by the Company and its
Subsidiaries and any information with respect to such property that is
reasonably necessary to complete such returns. The portion of the consideration
allocable to the real property of the Company and its Subsidiaries shall be
determined by Parent in its reasonable discretion.

                  Section 5.8 Indemnification; Directors and Officers Insurance.

                  (a) For six years from and after the Effective Time, Parent
agrees to cause the Surviving Corporation to, and shall guarantee the obligation
of the Surviving Corporation to, indemnify and hold harmless all past and
present officers and directors of the Company and of its Subsidiaries to the
same extent such Persons are indemnified as of the date of this Agreement by the
Company pursuant to the Company's Certificate of Incorporation, By-Laws or
agreements in existence on the date hereof for acts or omissions occurring at or
prior to the Effective Time.

                  (b) Parent shall provide, or shall cause the Surviving
Corporation to provide, for an aggregate period of not less than six years from
the Effective Time, the Company's current


                                       30
<PAGE>   31
directors and officers an insurance and indemnification policy that provides
coverage for events occurring prior to the Effective Time (the "D&O Insurance")
that is substantially similar (with respect to limits and deductibles) to the
Company's existing policy or, if substantially equivalent insurance coverage is
unavailable, the best available coverage; provided, however, that the Surviving
Corporation shall not be required in any year to expend more than $360,000 for
such coverage (the "Maximum Premium"), and provided, further, that if the
Surviving Corporation is unable to obtain the amount of such insurance required
by this Section 5.8(b) for such aggregate premiums, the Surviving Corporation
shall purchase as much insurance as is obtainable for an aggregate annual
premium of $360,000.

                  (c) From and after the Effective Time, to the full extent
permitted by the law, Parent shall, and shall cause the Company (or any
successor to the Company) to, indemnify, defend and hold harmless the present
officers and directors of the Company and its Subsidiaries (each an "Indemnified
Party") against all losses, claims, damages, liabilities, fees and expenses
(including reasonable attorneys' fees and disbursements), judgments, fines and
amounts paid in settlement (collectively, "Losses") arising out of actions or
omissions occurring at or prior to the Effective Time in connection with this
Agreement, the Company Stockholder Agreement and the Transactions; provided,
however, that an Indemnified Party shall not be entitled to indemnification
under this Section 5.8(c) for Losses arising out of actions or omissions by the
Indemnified Party constituting (i) a breach of this Agreement or the Company
Stockholder Agreement, (ii) grossly negligent or criminal conduct or fraud, or
(iii) any violation of federal, state or foreign securities laws. In order to be
entitled to indemnification under this Section 5.8(c), an Indemnified Party must
give Parent and the Company prompt written notice of any third party claim which
may give rise to any indemnify obligation under this Section 5.8(c), and Parent
and the Company shall have the right to assume the defense of any such claim
through counsel of their own choosing, subject to such counsel's reasonable
judgment that separate defenses that would create a conflict of interest on the
part of such counsel are not available. If Parent and the Company do not assume
any such defense, they shall be liable for all reasonable costs and expenses of
defending such claim incurred by the Indemnified Party, including reasonable
fees and disbursements of counsel, and shall advance such reasonable costs and
expenses to the Indemnified Party; provided, however, that such advance shall be
made only after receiving an undertaking from the Indemnified Party that such
advance shall be repaid if it is determined that such Indemnified Party is not
entitled to indemnification therefor. Neither Parent nor the Company shall be
liable under this Section 5.8(c) for any Losses resulting from any settlement,
compromise or offer to settle or compromise any such claim or litigation or
other action, without the prior written consent of Parent and the Company.

                  (d) In the event the Surviving Corporation or any successor to
the Surviving Corporation (i) consolidates with or merges into any other Person
and shall not be the continuing or surviving corporation or entity in such
consolidation or merger or (ii) transfers all or substantially all its
properties and assets to any Person, then, and in each case, proper provision
shall be made so that the successors of the Surviving Corporation honor the
obligations of the Company set forth in this Section 5.8.

                  Section 5.9 Notification of Certain Matters. Parent shall use
its best efforts to give prompt notice to the Company, and the Company shall use
its best efforts to give prompt notice to Parent, of: (i) the occurrence, or
non-occurrence, of any event the occurrence, or non-occurrence,


                                       31
<PAGE>   32
of which it is aware and which would be reasonably likely to cause (x) any
representation or warranty by it contained in this Agreement to be untrue or
inaccurate in any material respect or (y) any covenant, condition or agreement
contained in this Agreement not to be complied with or satisfied in all material
respects by it, (ii) any failure of Parent or the Company, as the case may be,
to comply in a timely manner with or satisfy any covenant, condition or
agreement to be complied with or satisfied by it hereunder or (iii) any change
or event which would be reasonably likely to have a Material Adverse Effect on
the Company; provided, however, that the delivery of any notice pursuant to this
Section 5.9 shall not limit or otherwise affect the remedies available hereunder
to the party receiving such notice.

                  Section 5.10 Employee Benefit Plans and Agreements

                  (a) Company Plans. Parent shall cause the Surviving
Corporation to perform the obligations of the Company under, and comply with,
the Employee Agreements and to maintain through December 31, 1999 the Company
Plans (other than plans providing for the issuance of Company Common Stock or
based on the value of Company Common Stock) in effect on the date of this
Agreement; provided, however, that Parent shall have no obligation to continue
or renew any Employee Agreement or Company Plan that may be terminated in
accordance with its terms; and provided, further, however, that nothing in this
Agreement shall confer on any individual any right to employment, compensation
for employment, or employee benefits. Notwithstanding the foregoing, Parent
shall have the right, at its option, to replace the Company Plans with its own
benefit plans provided such plans are in the aggregate comparable (taking into
account all relevant factors) with the Company Plans.

                  (b) Credit for Prior Service; Waiver of Pre-existing
Conditions. In the event that Parent shall merge any Company Plan with any
benefit plan of Parent or otherwise modify any Company Plan, prior service with
the Company or any of its Subsidiaries will be counted for purposes of employee
eligibility, seniority and vesting under such benefit plan, and any pre-existing
condition shall be waived for each employee so long as such employee has had
medical coverage under the Company Plans for at least six months immediately
prior to the Effective Time.

                  (c) Change of Control. Parent agrees that for purposes of any
of the Company Plans conferring rights on a current or former employee, officer
or director as a result of a change of control of the Company, the consummation
of the Merger shall be deemed to constitute a "Change of Control" (as that term
is defined in such Company Plans).

                  Section 5.11 Performance by Sub. Parent shall cause Sub to
comply with each of its obligations hereunder and pursuant to the Company
Stockholder Agreement, including, without limitation, causing Sub to consummate
the Merger as contemplated herein, and Parent hereby guarantees the performance
by Sub of such obligations. Parent shall cause Sub to vote any shares of Common
Stock owned by the Sub on the record date for the Stockholder Meeting to be
voted for approval of this Agreement and the Merger.

                  Section 5.12 Additional Consents and Approvals. The Company
and Parent agree that they will cooperate and use their commercially reasonable
efforts to seek any waiver and/or consent required such that consummation of the
Transactions will not constitute a default under the


                                       32
<PAGE>   33
terms of (1) that certain Credit Agreement, by and among NRG Generating (Newark)
Cogeneration Inc. and NRG Generating (Parlin) Cogeneration Inc., Credit Suisse,
Greenwich Funding Corporation and any Purchasing Lender as Lender and Credit
Suisse as Agent, dated as of May 17, 1996, as amended by Amendment Number 1,
dated June 28, 1996 and (2) that certain Construction and Term Loan Agreement,
by and among NRG (Morris) Cogen, L.L.C., The Chase Manhattan Bank and other
Banks as Lenders, The Chase Manhattan Bank as Agent and The Chase Manhattan Bank
as Collateral Agent, dated September 15, 1997, as amended by the Amendment and
Consent, dated December 10, 1997.

                                   ARTICLE VI

                       CONDITIONS PRECEDENT TO THE MERGER

                  Section 6.1 Conditions to Each Party's Obligation to Effect
the Merger. The respective obligations of each party to effect the Merger shall
be subject to the fulfillment at or prior to the Effective Time of the following
conditions:

                  (a) Stockholder Approval. This Agreement shall have been duly
approved by the requisite vote of stockholders of the Company in accordance with
applicable law and the Certificate of Incorporation and By-laws of the Company.

                  (b) HSR and Other Approvals. (i) The waiting period (and any
extension thereof) applicable to the consummation of the Merger under the HSR
Act shall have expired or been terminated.

                           (ii) All authorizations, consents, orders,
declarations or approvals of, or filings with, or terminations or expirations of
waiting periods imposed by, any Governmental Entity, which the failure to
obtain, make or occur would have the effect of making the Merger or any of the
transactions contemplated hereby illegal or would have, individually or in the
aggregate, a Material Adverse Effect on Parent (assuming the Merger had taken
place), shall have been obtained, shall have been made or shall have occurred.

                  (c) Governmental Actions. No statute, rule, regulation,
legislation, interpretation, judgment, order or injunction shall be enacted,
entered, enforced, promulgated, amended or become applicable to this Agreement
or the Merger and no other action shall have been taken by any court or other
Governmental Entity other than the application to the Merger of the waiting
period under the HSR Act, that, in each case, would be reasonably expected to
result in any of the following effects: (i) challenging the acquisition by
Parent or Sub of any Company Common Stock, seeking to restrain or prohibit the
making or consummation of the Merger or any other Transaction, (ii) seeking to
prohibit or limit the ownership or operation by the Company, Parent or any of
their respective Subsidiaries of any material portion of the business or assets
of the Company, Parent or any of their respective Subsidiaries, or to compel the
Company, Parent or any of their respective Subsidiaries to dispose of or hold
separate any material portion of the business or assets of the Company, Parent
or any of their respective Subsidiaries, (iii) seeking to impose limitations on
the ability of Parent or Sub to acquire or hold, or exercise full rights of
ownership of, any shares of Company Common Stock, including the right to vote
the Company Common Stock purchased by it on all matters properly


                                       33
<PAGE>   34
presented to the stockholders of the Company, (iv) seeking to prohibit Parent or
any of its Subsidiaries from effectively controlling in any material respect the
business or operations of the Company and its Subsidiaries in connection with
the Offer, the Merger or the Agreement, or (v) which otherwise is reasonably
likely to have a Material Adverse Effect on the Company.

                  Section 6.2 Conditions to Obligation of the Company to Effect
the Merger. The obligation of the Company to effect the Merger shall be subject
to the fulfillment at or prior to the Effective Time of the following additional
conditions:

                  (a) Performance of Obligations. Each of Parent and Sub shall
have performed in all material respects each of its agreements contained in this
Agreement required to be performed on or prior to the Effective Time.

                  (b) Representations and Warranties. Each of the
representations and warranties of Parent and Sub contained in this Agreement
shall be true and correct, provided that such representations and warranties
shall be deemed to be true and correct unless the failure of such
representations and warranties to be so true and correct would have a Material
Adverse Effect on Parent or would prevent Parent from consummating the
transactions contemplated by the Agreement, in each case as if such
representations and warranties were made at the time of such termination (except
to the extent such representations or warranties expressly relate to an earlier
date).

                  (c) Certain Consents. In obtaining any approval or consent
required to consummate any of the transactions contemplated herein, no
Governmental Entity shall have imposed or shall have sought to impose any
condition, penalty or requirement which, in the reasonable opinion of the
Company, individually or in the aggregate, would have a Material Adverse Effect
on Parent (assuming the consummation of the Merger).

                  Section 6.3 Conditions to Obligations of Parent and Sub to
Effect the Merger. The obligations of Parent and Sub to effect the Merger shall
be subject to the fulfillment at or prior to the Effective Time of the following
additional conditions:

                  (a) Performance of Obligations. The Company shall have
complied with the provisions of Section 4.1 of the Agreement, and the Company
shall have complied with any agreement or covenant in any material respect of
the Company to be performed or complied with by it under the Agreement.

                  (b) Representations and Warranties. Each of the
representations and warranties of the Company contained in this Agreement shall
be true and correct, provided that such representations and warranties shall be
deemed to be true and correct unless the failure of such representations and
warranties to be so true and correct would have a Material Adverse Effect on the
Company or would prevent the Company from consummating the transactions
contemplated by the Agreement, in each case as if such representations and
warranties were made at the time of such termination (except to the extent such
representations or warranties expressly relate to an earlier date).

                  (c) Litigation. There shall not be instituted or pending any
suit, action or proceeding by any Governmental Entity or by any other Person
initiated as a result of this Agreement


                                       34
<PAGE>   35
or any transactions contemplated hereby (i) challenging the acquisition by
Parent or Sub of any Company Common Stock, seeking to restrain or prohibit the
making or consummation of the Merger or any other Transaction, (ii) seeking to
prohibit or limit the ownership or operation by the Company, Parent or any of
their respective Subsidiaries of any material portion of the business or assets
of the Company, Parent or any of their respective Subsidiaries, or to compel the
Company, Parent or any of their respective Subsidiaries to dispose of or hold
separate any material portion of the business or assets of the Company, Parent
or any of their respective Subsidiaries, (iii) seeking to impose limitations on
the ability of Parent or Sub to acquire or hold, or exercise full rights of
ownership of, any shares of Company Common Stock, including the right to vote
the Company Common Stock purchased by it on all matters properly presented to
the stockholders of the Company, (iv) seeking to prohibit Parent or any of its
Subsidiaries from effectively controlling in any material respect the business
or operations of the Company and its Subsidiaries in connection with the Merger
or the Agreement, or (v) which otherwise is reasonably likely to have a Material
Adverse Effect on the Company.

                  (d) Material Adverse Effect. Since the date of the Agreement,
there shall not have occurred any event, change, effect or development that,
individually or in the aggregate, has had or would be reasonably expected to
have a Material Adverse Effect on the Company.


                                   ARTICLE VII

                        TERMINATION, AMENDMENT AND WAIVER

                  Section 7.1 Termination. This Agreement may be terminated at
any time prior to the Effective Time, whether before or after any approval of
the matters presented in connection with the Merger by the stockholders of the
Company or Parent:

                  (a) by mutual written consent of Parent and the Company;

                  (b) by either Parent or the Company:

                  (i) if the Merger has not been effected on or prior to the
         close of business on February 28, 2000 (the "Outside Date"); provided,
         however, that the right to terminate this Agreement pursuant to this
         Section 7.1(b)(i) shall not be available to any party whose material
         and willful failure to fulfill any of its obligations contained in this
         Agreement has been the cause of, or resulted in, the failure of the
         Merger to have occurred on or prior to the Outside Date; provided;
         however that if the sole reason that the Merger shall not have been
         consummated by the Outside Date is the failure to hold the Stockholder
         Meeting by February 28, 2000, the Outside Date shall be extended to
         March 31, 2000;

                  (ii) if any court or other Governmental Entity having
         jurisdiction over a party hereto shall have issued an order, decree or
         ruling or taken any other action permanently enjoining, restraining or
         otherwise prohibiting the transactions contemplated by this Agreement
         and such order, decree, ruling or other action shall have become final
         and nonappealable; or



                                       35
<PAGE>   36
                  (iii) if the stockholders of the Company fail to approve this
         Agreement and the Merger at the Stockholder Meeting or any adjournment
         or postponement thereof;

                  (c) by Parent if prior to the Effective Time, the Company's
Board of Directors or any committee thereof shall have withdrawn or modified in
a manner adverse to Sub or Parent its approval or recommendation of the
Transactions or shall have recommended or approved a Company Superior Proposal,
or shall have resolved to do any of the foregoing;

                  (d) by the Company, upon approval of its Board of Directors in
accordance with Section 4.2(b); provided, however, that any termination of this
Agreement pursuant to this Section 7.1(d) shall not be effective until the
Company has made full payment of all amounts provided under Section 5.4(b);

                  (e) by either Parent or the Company if the other party shall
have breached or failed to comply in any material respect with any of its
covenants or agreements other than Section 4.1 contained in this Agreement
required to be performed or complied with prior to the date of such termination,
which failure to comply has not been cured within thirty business days following
receipt by such other party of written notice from the non-breaching party of
such failure to comply or by Parent if the Company shall have breached or failed
to comply with Section 4.1; or

                  (f) by either Parent or the Company if there has been a breach
by the other party (in the case of Parent, including any material breach by Sub)
of any representation or warranty that individually or in the aggregate has a
Material Adverse Effect on the breaching party or would prevent such breaching
party from consummating the transactions contemplated by this Agreement.

                  The right of any party hereto to terminate this Agreement
pursuant to this Section 7.1 shall remain operative and in full force and effect
regardless of any investigation made by or on behalf of any party hereto, any
Person controlling any such party or any of their respective officers or
directors, whether prior to or after the execution of this Agreement.

                  Section 7.2 Effect of Termination. In the event of termination
of this Agreement by either Parent or the Company, as provided in Section 7.1,
this Agreement shall forthwith become void and there shall be no liability
hereunder on the part of the Company, Parent, Sub or their respective officers
or directors (except for the last sentence of Section 5.3 and the entirety of
Sections 5.4, 8.6, 8.7, 8.9 and 8.10, which shall survive the termination);
provided, however, that nothing contained in this Section 7.2 shall relieve any
party hereto from any liability for any willful breach of a representation or
warranty contained in this Agreement or the breach of any covenant contained in
this Agreement.

                  Section 7.3 Amendment. This Agreement may be amended by the
parties hereto, by or pursuant to action taken by their respective Boards of
Directors, at any time before or after approval of the matters presented in
connection with the Merger by the stockholders of the Company, but, after any
such approval, no amendment shall be made which by law requires further approval
by such stockholders without such further approval. This Agreement may not be
amended except by an instrument in writing signed on behalf of each of the
parties hereto.



                                       36
<PAGE>   37
                  Section 7.4 Waiver. At any time prior to the Effective Time,
the parties hereto may (i) extend the time for the performance of any of the
obligations or other acts of the other parties hereto, (ii) waive any
inaccuracies in the representations and warranties of the other parties
contained herein or in any document delivered pursuant hereto and (iii) waive
compliance with any of the agreements or conditions contained herein which may
legally be waived. Any agreement on the part of a party hereto to any such
extension or waiver shall be valid only if set forth in an instrument in writing
signed on behalf of such party.

                                  ARTICLE VIII

                               GENERAL PROVISIONS

                  Section 8.1 Non-Survival of Representations and Warranties.
The representations and warranties in this Agreement or in any instrument
delivered pursuant to this Agreement shall terminate at the Effective Time.

                  Section 8.2 Notices. All notices and other communications
hereunder shall be in writing and shall be deemed given when delivered
personally, one day after being delivered to an overnight courier or when sent
via facsimile (with a confirmatory copy sent by overnight courier) to the
parties at the following addresses (or at such other address for a party as
shall be specified by like notice):

                  (a)      if to Parent or Sub, to

                           Calpine Corporation
                           50 West San Fernando Street
                           San Jose, CA  95113
                           Attention:  John T. King, Vice President
                           Fax:  (408) 995-0505

                           with a copy to:

                           Howard, Smith & Levin LLP
                           1330 Avenue of the Americas
                           New York, NY  10019
                           Attention:  William R. Collins
                           Fax:  (212) 841-1010

                  (b)      if to the Company, to

                           Cogeneration Corporation of America.
                           One Carlson Parkway, Suite 240
                           Minneapolis, Minnesota 55447-4454
                           Attention:      Julie A. Jorgensen
                                           President and Chief Executive Officer
                           Facsimile No.:  (612) 745-7901



                                       37
<PAGE>   38
                           with a copy to:

                           Kaplan, Strangis and Kaplan, P.A.
                           5500 Norwest Center
                           Minneapolis, Minnesota 55402
                           Attention: Bruce J. Parker
                           Facsimile No.: (612) 375-1143

                  Section 8.3 Interpretation. When a reference is made in this
Agreement to a Section, such reference shall be to a Section of this Agreement
unless otherwise indicated. The table of contents and headings contained in this
Agreement are for reference purposes only and shall not affect in any way the
meaning or interpretation of this Agreement. Whenever the words "include,"
"includes" or "including" are used in this Agreement, they shall be deemed to be
followed by the words "without limitation."

                  Section 8.4 Counterparts. This Agreement may be executed in
counterparts, all of which shall be considered one and the same agreement, and
shall become effective when one or more counterparts have been signed by each of
the parties and delivered to the other parties.

                  Section 8.5 Entire Agreement; No Third-Party Beneficiaries.
This Agreement, except and as provided in the last sentence of Section 5.3,
constitutes the entire agreement and supersedes all prior agreements and
understandings, both written and oral, among the parties with respect to the
subject matter hereof. Except as provided pursuant to Section 5.8 and 5.10, this
Agreement is not intended to confer upon any Person other than the parties
hereto any rights or remedies hereunder.

                  Section 8.6 Governing Law. This Agreement shall be governed
by, and construed in accordance with, the laws of the State of Delaware,
regardless of the laws that might otherwise govern under applicable principles
of conflicts of laws thereof.

                  Section 8.7 Assignment. Neither this Agreement nor any of the
rights, interests or obligations hereunder shall be assigned by any of the
parties hereto (whether by operation of law or otherwise) without the prior
written consent of the other parties.

                  Section 8.8 Severability. If any term or other provision of
this Agreement is invalid, illegal or incapable of being enforced by any rule of
law, or public policy, all other terms, conditions and provisions of this
Agreement shall nevertheless remain in full force and effect so long as the
economic and legal substance of the transactions contemplated hereby are not
affected in any manner materially adverse to any party. Upon such determination
that any term or other provision is invalid, illegal or incapable of being
enforced, the parties shall negotiate in good faith to modify this Agreement so
as to effect the original intent of the parties as closely as possible in a
mutually acceptable manner in order that the transactions contemplated by this
Agreement may be consummated as originally contemplated to the fullest extent
possible.

                  Section 8.9 Enforcement of this Agreement. The parties hereto
agree that


                                       38
<PAGE>   39
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with their specific wording or were
otherwise breached. It is accordingly agreed that the parties hereto shall be
entitled to seek an injunction or injunctions to prevent breaches of this
Agreement and to enforce specifically the terms and provisions hereof in any
court of the United States or any state having jurisdiction, such remedy being
in addition to any other remedy to which any party is entitled at law or in
equity.

                  Section 8.10 Consent to Jurisdiction. Each of the parties
hereto (a) consents to submit itself to the non-exclusive personal jurisdiction
of any Federal court located in the State of Delaware or any Delaware state
court in the event any dispute arises out of this Agreement or any of the
transactions contemplated by this Agreement, and (b) agrees that it will not
attempt to deny or defeat such personal jurisdiction by motion.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]




                                       39
<PAGE>   40
         IN WITNESS WHEREOF, Parent, Sub and the Company have caused this
Agreement to be signed by their respective officers thereunto duly authorized
all as of the date first written above.

                                   COGENERATION CORPORATION OF AMERICA



                                   By: /s/ Julie A. Jorgensen
                                      ------------------------------------------
                                           Julie A. Jorgensen
                                           President and Chief Executive Officer


                                   CALPINE CORPORATION



                                   By: /s/ John T. King
                                      ------------------------------------------
                                           John T. King
                                           Vice President


                                   CALPINE EAST ACQUISITION CORP.


                                   By: /s/ John T. King
                                      ------------------------------------------
                                           John T. King
                                           Vice President




                                       40
<PAGE>   41
                                    EXHIBIT A

                      Form of Certificate of Incorporation


         The following sentence shall be added at the end of Article Seventh of
the Company's Amended and Restated Certificate of Incorporation:

         The provisions of this Article Seventh shall not apply to the transfer
         of shares of the Corporation's common stock by NRG Energy, Inc. to
         Calpine East Acquisition Corp. in contemplation of closing the merger
         contemplated by the agreement and plan of merger dated August __, 1999
         among the Corporation, Calpine Corporation and Calpine East Acquisition
         Corp.

<PAGE>   1
                                                                     Exhibit (3)

                    CONTRIBUTION AND STOCKHOLDERS AGREEMENT



         CONTRIBUTION AND STOCKHOLDERS AGREEMENT (this "Agreement"), dated as of
August 26, 1999, among CALPINE EAST ACQUISITION CORP., a Delaware corporation
(the "Company"), CALPINE CORPORATION, a Delaware corporation ("Buyer"), and NRG
ENERGY, INC., a Delaware corporation ("NRG", and together with the Buyer, the
"Stockholders").

                              W I T N E S S E T H:

         WHEREAS, on the date hereof, the Company is authorized by its
Certificate of Incorporation to issue Capital Stock consisting of 1,000 shares
of common stock, without par value (the "Common Stock");

         WHEREAS, the Company has been formed for the purpose of entering into
an Agreement and Plan of Merger, dated as of the date hereof (the "Merger
Agreement"), and, subject to satisfaction or waiver of the conditions set forth
in the Merger Agreement, consummating a merger (the "Merger") with and into
Cogeneration Corporation of America, a Delaware corporation ("Cogen"), with
Cogen continuing as the surviving corporation;

         WHEREAS, it is contemplated that immediately prior to and following the
consummation of the Merger, NRG will own 20% of the issued and outstanding
shares of Capital Stock of the Company and the Buyer will own 80% of the issued
and outstanding shares of Capital Stock of the Company; and

         WHEREAS, the parties hereto deem it in their best interests and in the
best interests of the Company to provide consistent and uniform management for
the Company and desire to enter into this Agreement in order to effectuate that
purpose and to set forth their respective rights and obligations in connection
with their proposed investment in the Company.

         NOW, THEREFORE, in consideration of the mutual agreements and
understandings set forth herein, the parties hereto, intending to be legally
bound, hereby agree as follows:
<PAGE>   2
                                    ARTICLE I

                                   DEFINITIONS

                  Section 1.1. Certain Definitions. As used in this Agreement,
the following terms shall have the following respective meanings:

                  "Actual Adjusted Net Income" has the meaning specified in
Section 9.3(a).

                  "Adjustment Amount" has the meaning specified in Section
5.1(a).

                  "Affiliate" has the meaning set forth in Rule 12b-2 of the
General Rules and Regulations under the Exchange Act.

                  "Agreement" means this Contribution and Stockholders Agreement
as in effect on the date hereof and as hereafter from time to time amended,
modified or supplemented in accordance with the terms hereof.

                  "Bankruptcy Code" means the United States Bankruptcy Code, 11
U.S.C. Sec. 101 et seq., as now in effect and as from time to time hereafter
amended, and any successor or similar statute.

                  "Board of Directors" means the Board of Directors of the
Company as from time to time hereafter constituted.

                  "Buyer Directors" has the meaning specified in Section 2.3(b).

                  "By-Laws" means the Amended and Restated By-Laws of the
Company in the form set forth as Exhibit D hereto, and as hereafter from time to
time amended, modified, supplemented or restated in accordance with the terms
hereof and pursuant to applicable law.

                  "Cancelled Options" has the meaning specified in Section
5.1(a).

                  "Capital Stock" means and includes (i) any and all shares,
interests, participations or other equivalents of or interests in (however
designated) corporate stock of any Person, including, without limitation, shares
of preferred or preference stock, (ii) all partnership interests (whether
general or limited) in any Person which is a partnership, (iii) all membership
interests or limited liability company interests in any Person which is a
limited liability company, and (iv) all equity or ownership interests in any
Person of any other type.

                  "Cash Equivalents" means

                  (a) marketable obligations maturing within 180 days after
acquisition thereof issued or fully guaranteed by the United States of America
or an instrumentality or agency thereof,

                  (b) open market commercial paper, maturing within 180 days
after acquisition thereof, which has the highest credit rating of either
Standard & Poor's Corporation or Moody's Investors Service, Inc., issued by a
corporation (other than the Company or any of its Subsidiaries or Affiliates)
organized under the laws of any State of the United States of America or of the
District of Columbia, and
<PAGE>   3
                  (c) certificates of deposit or bankers acceptances or other
obligations maturing within 180 days after acquisition thereof issued by a
domestic commercial bank which is a member of the Federal Reserve System and has
capital, surplus and undivided profits in excess of $500,000,000.

                  "Certificate of Incorporation" means the Amended and Restated
Certificate of Incorporation of the Company in the form set forth as Exhibit C
hereto, and as hereafter from time to time amended, modified, supplemented or
restated in accordance with the terms hereof and pursuant to applicable law.

                  "Cogen" has the meaning specified in the Recitals.

                  "Commission" means the Securities and Exchange Commission and
any successor commission or agency having similar powers.

                  "Common Stock" means the common stock, without par value, of
the Company and any Capital Stock of the Company that is not limited to a fixed
sum or percentage of par or stated value in respect to the rights of the holders
thereof to participate in dividends or in the distribution of assets upon any
liquidation, dissolution or winding up of the Company.

                  "Company" has the meaning specified in the first paragraph of
this Agreement, together with any of its successors or assigns (including,
without limitation, Cogen following the consummation of the Merger).

                  "Company Sale" has the meaning specified in Section 8.2(a).

                  "Contribution Date" has the meaning specified in Section 5.1.

                  "Drag-Along Notice" has the meaning specified in Section
8.2(a).

                  "Drag Along Right" has the meaning specified in Section
8.2(b).

                  "Disposing Stockholder" has the meaning specified in Section
8.3(b).

                  "Effective Date" means the date on which the Effective Time
(as such term is defined in the Merger Agreement) occurs.

                  "Exchange Act" means, as of any date, the Securities Exchange
Act of 1934, as amended.

                  "Fully Diluted Common Stock" means at any time all shares of
Common
<PAGE>   4
Stock then issued and outstanding and all shares of Common Stock issuable upon
the exercise of any then outstanding warrants, options, conversion rights or
other rights to subscribe for, purchase or acquire shares of Common Stock that
are at the time exercisable.

                  "GAAP" means generally accepted accounting principles in the
United States of America in effect from time to time, applied on a consistent
basis both as to classification of items and amounts.

                  "HSR Act" means the Hart-Scott-Rodino Antitrust Improvements
Act of 1976, as amended.

                  "Independent Third Party" has the meaning specified in Section
8.2(a).

                  "Management Fee" has the meaning specified in Section 9.3(a).

                  "Merger" has the meaning specified in the Recitals.

                  "Merger Agreement" has the meaning specified in the Recitals.

                  "Merger Price" has the meaning specified in Section 5.1(a).

                  "NASD" means the National Association of Securities Dealers,
Inc. and its successors and assigns.

                  "Notice of Exercise" has the meaning specified in Section
8.1(a).

                  "NRG Director" has the meaning specified in Section 2.3(b).

                  "Offered Securities" has the meaning specified in Section
8.1(a).

                  "Option" has the meaning specified in Section 8.4(a).

                  "Option Period" has the meaning specified in Section 8.4(a).

                  "Option Price" has the meaning specified in Section 8.4(b).

                  "Permitted Transferee" has the meaning specified in Section
7.2.

                  "Person" means an individual or a corporation, association,
partnership, limited liability company, joint venture, organization, business,
trust or any other entity or organization, including a government or any
subdivision or agency thereof.
<PAGE>   5
                  "Pro Rata Portion" means, with reference to any Stockholder at
any time, a fraction, the numerator of which is the number of shares of Common
Stock then issued and outstanding and held by such Stockholder, and the
denominator of which is the aggregate number of shares of Common Stock then
issued and outstanding and held by the Stockholders taken together.

                  "Projected Adjusted Net Income" has the meaning set forth in
Section 9.3(a).

                  "Proposed Purchaser" has the meaning specified in Section
8.3(b).

                  "Public Offering" means a public offering and sale of equity
securities of the Company pursuant to an effective registration statement under
the Securities Act.

                  "Purchase Offer" has the meaning specified in Section 8.3(b).

                  "Quorum of the Board" has the meaning specified in Section
2.3(d).

                  "Registrable Securities" means the following: (a) all shares
of Common Stock issued or issuable now or hereafter owned of record or
beneficially by any Stockholder and (b) any shares of Capital Stock issued or
issuable by the Company in respect of any shares of Common Stock referred to in
the foregoing clause (a) by way of a stock dividend or stock split or in
connection with a combination or subdivision of shares, reclassification,
recapitalization, merger, consolidation or other reorganization of the Company.

                  As to any particular Registrable Securities that have been
issued, such securities shall cease to be Registrable Securities when (i) a
registration statement with respect to the sale of such securities shall have
become effective under the Securities Act and such securities shall have been
disposed of under such registration statement, (ii) they shall have been
distributed to the public pursuant to Rule 144 under the Exchange Act, (iii)
they shall have been otherwise transferred or disposed of, and new certificates
therefor not bearing a legend restricting further transfer shall have been
delivered by the Company, and subsequent transfer or disposition of them shall
not require their registration or qualification under the Securities Act or any
similar state law then in force, (iv) they shall have ceased to be outstanding,
or (v) with respect to the Registrable Securities held by any Person, when such
Registrable Securities, when aggregated with the Registrable Securities held by
such Person's Affiliates, constitute 1% or less of the shares of Common Stock at
the time outstanding.

                  "Registration Expenses" means any and all out-of-pocket
expenses
<PAGE>   6
incident to the Company's performance of or compliance with Section 10 hereof,
including, without limitation, all Commission, stock exchange and NASD
registration and filing fees, all fees and expenses of complying with securities
and blue sky laws (including the reasonable fees and disbursements of
underwriters' counsel in connection with blue sky qualifications and NASD
filings), all fees and expenses of the transfer agent and registrar for the
Registrable Securities, all printing expenses, the fees and disbursements of
counsel for the Company and of its independent public accountants, including the
expenses of any special audits or "cold comfort" letters required by or incident
to such performance and compliance, but excluding underwriting discounts and
commissions and applicable transfer and documentary stamp taxes, if any, which
shall be borne by the seller of the securities in all cases.

                  "Restricted Period" means the three-year period commencing on
the Effective Date.

                  "Securities Act" means, as of any date, the Securities Act of
1933, as amended.

                  "Stockholder" means (i) the Buyer, (ii) NRG or (iii) each
Permitted Transferee of any such Person who becomes a party to or bound by the
provisions of this Agreement in accordance with the terms hereof.

                  "Subsidiary" means as to any Person a corporation of which
outstanding shares of Common Stock having the power to elect a majority of the
Board of Directors of such corporation are at the time owned, directly or
indirectly through one or more intermediaries, or both, by such Person.

                  "Total Equity Value of the Company" has the meaning specified
in Section 5.1(a).

                  "Transfer" has the meaning specified in Section 7.1.

                  "Transfer Notice" has the meaning specified in Section 8.1(a).

                  "Transfer Offer" has the meaning specified in Section 8.1(a).

                  "Transfer Offer Price Per Security" shall have the meaning
specified in Section 8.1(a).

                  "Valuation Notice" has the meaning specified in Section
8.4(b).

                  "Valuing Investment Bank" has the meaning specified in Section
8.4(b).

<PAGE>   7


         "Wholly-Owned Subsidiary" means, with respect to any Person, any
Subsidiary of such Person all of the Capital Stock (and all options, warrants,
conversion rights and other rights to subscribe for, purchase or acquire such
Capital Stock) of which, other than directors' qualifying shares, are owned,
beneficially and of record, by such Person or one or more Wholly-Owned
Subsidiaries of such Person.

                                   ARTICLE II

                                   THE COMPANY

         Section 2.1 Organizational Documents. Attached hereto as Exhibits A and
B, respectively, are the current certificate of incorporation and by-laws of the
Company. On the Contribution Date but prior to the making of the contributions
referred to in Section 5.1 hereof, the Buyer and the Company shall cause the
Amended and Restated Certificate of Incorporation of the Company in the form set
forth as Exhibit C hereto to be filed with the Secretary of State of the State
of Delaware, and the Amended and Restated By-Laws of the Company in the form set
forth as Exhibit D hereto shall be approved by the Board of Directors.

         Section 2.2 Capitalization. Prior to the Contribution Date, the
capitalization of the Company shall be 1,000 shares of Common Stock, all of
which shall be held by the Buyer.

         Section 2.3 Board of Directors. The following provisions shall apply
with respect to the Board of Directors of the Company commencing on the
Contribution Date:

                         (a) Conduct of Business. The parties hereto confirm
                    that it is their intention that the business and affairs of
                    the Company shall be managed by its Board of Directors in
                    the best interests of the Company.

                         (b) Board of Directors. The Board of Directors shall be
                    composed of no more than seven directors. Each Stockholder
                    agrees to vote its shares of Common Stock, whether at a
                    duly-convened meeting or by written consent, to elect no
                    more than seven directors, one of whom shall be nominated by
                    NRG (the "NRG Director") and the remainder of whom shall be
                    nominated by the Buyer (the "Buyer Directors").

                         (c) Removal; Vacancies. Any director may be removed
                    from the Board of Directors, with or without cause, only
                    upon the affirmative vote of the Stockholders and in
                    accordance with the terms of this Section 2.3(c). The NRG
                    Director shall not be removed, with or without cause,
                    without the prior written consent of NRG. NRG agrees to vote
                    all of its shares of Common Stock for the removal of a Buyer
                    Director upon the request of the Buyer, and agrees not to
                    vote any of its shares of Common Stock for the removal of
                    any Buyer Director under any other circumstance. The Buyer
                    agrees to vote all of its shares of Common Stock for the
                    removal of the NRG Director upon the request of NRG, and
                    agrees not to vote any of its shares of Common Stock of the
                    Company for the removal of the NRG Director under any other
                    circumstance. In the event that any Director is unwilling or
                    unable (by reason of death, resignation or

<PAGE>   8

                    otherwise) to serve as such or is removed in accordance with
                    the terms of this Section 2.3(c), then the Stockholders
                    shall promptly elect the successor or replacement to such
                    Director upon the nomination of the Stockholder which
                    appointed such Director.

                         (d) Quorum of the Board of Directors. A quorum for any
                    meeting of the Board of Directors shall be at least a
                    majority of the directors (a "Quorum of the Board");
                    provided, that at least 48 hours prior written notice of
                    such meeting is duly given to the NRG Director. No action
                    may be taken by the Board of Directors at any meeting unless
                    a Quorum of the Board is present at the time such action is
                    taken.

                         (e) Committees of the Board of Directors. The Board of
                    Directors shall not have any committees, unless approved by
                    the unanimous consent of all members of the Board of
                    Directors or unless the NRG Director is a member of such
                    committee.

                   Section 2.4 No Conflict with Agreement. Each Stockholder
shall vote its shares of Common Stock, and shall take all actions necessary, to
ensure that the Certificate of Incorporation and By-Laws do not, at any time,
conflict with the provisions of this Agreement. In the event of any conflict
between this Agreement and the Certificate of Incorporation or the By-Laws, the
provisions of this Agreement shall govern and the Company and the Stockholders
shall take action as is required to ensure that the Certificate of Incorporation
and the By-Laws do not conflict with this Agreement.


<PAGE>   9



                                   ARTICLE III

                         REPRESENTATIONS AND WARRANTIES

          Section 3.1 Representations and Warranties of NRG.

                         (a) Organization. NRG is a corporation duly
                    incorporated, validly existing and in good standing under
                    the laws of the State of Delaware and is duly licensed or
                    qualified to transact business as a foreign corporation and
                    is in good standing in each jurisdiction in which the nature
                    of the business transacted by it or the character of the
                    properties owned or leased by it requires such licensing or
                    qualification.

                         (b) Due Authorization; Non-Contravention. The execution
                    and delivery by NRG of this Agreement and the performance by
                    NRG of its obligations hereunder have been duly authorized
                    by all requisite corporate action and will not violate any
                    provision (x) of the Certificate of Incorporation of NRG, as
                    amended, or the By-laws of NRG, as amended, (y) of law, any
                    order of any court or other agency of government, or (z) of
                    any indenture, agreement or other instrument to which NRG or
                    any of its properties or assets is bound, or conflict with,
                    result in a breach of or constitute (with due notice or
                    lapse of time or both) a default under any such indenture,
                    agreement or other instrument, or result in the creation or
                    imposition of any lien, charge, restriction, claim or
                    encumbrance of any nature whatsoever upon any of the
                    properties or assets of NRG, it being understood that, in
                    connection with the transactions contemplated by this
                    Agreement and the Merger Agreement, the parties will make
                    all requisite filings and otherwise comply with the
                    applicable requirements of (i) the HSR Act, (ii) the
                    Exchange Act and the Securities Act, (iii) state securities,
                    takeover or blue sky laws, and (iv) any other laws or
                    regulations.

                         (c) Binding Agreement. This Agreement has been duly
                    executed and delivered by NRG and, assuming the due
                    execution and delivery by the other parties hereto,
                    constitutes the legal, valid and binding obligation of NRG
                    enforceable in accordance with its terms.

                         (d) Ownership of Shares. NRG (or accounts controlled or
                    beneficially owned by NRG) is the lawful owner of 3,106,612
                    shares of common stock of Cogen, and has the power to vote
                    and dispose of such shares. To NRG's knowledge, such shares
                    of common stock are validly issued, fully paid and
                    nonassessable, with no personal liability attaching to the
                    ownership thereof. NRG has good title to its shares of
                    common stock, free and clear of any liens, adverse claims or
                    encumbrances whatsoever with respect to the ownership of or
                    the right to vote such shares. Such shares constitute all of
                    the shares of common stock of Cogen owned of record or
                    beneficially by NRG. NRG does not own any options to
                    purchase or rights to subscribe for or otherwise acquire any
                    securities of Cogen. Except as otherwise provided in this

<PAGE>   10

                    Agreement, NRG has the sole voting power and sole power to
                    issue instructions with respect to the matters set forth in
                    this Agreement, sole power of disposition, sole power to
                    demand appraisal rights and sole power to agree to all of
                    the matters set forth in this Agreement, in each case with
                    respect to all of the shares of common stock of Cogen owned
                    by NRG with no limitations, qualifications or restrictions
                    on such rights, subject to applicable securities laws and
                    the terms of this Agreement. The terms "beneficially own" or
                    "beneficial ownership" with respect to any securities shall
                    mean having "beneficial ownership" of such securities as
                    determined pursuant to Rule 13d-3 under the Exchange Act.

          Section 3.2 Representations and Warranties of the Buyer.

                         (a) Organization. The Buyer is a corporation duly
                    incorporated, validly existing and in good standing under
                    the laws of the State of Delaware and is duly licensed or
                    qualified to transact business as a foreign corporation and
                    is in good standing in each jurisdiction in which the nature
                    of the business transacted by it or the character of the
                    properties owned or leased by it requires such licensing or
                    qualification.

                         (b) Due Authorization; Non Contravention. The execution
                    and delivery by the Buyer of this Agreement and the
                    performance by the Buyer of its obligations hereunder have
                    been duly authorized by all requisite corporate action and
                    will not violate any provision (x) of the Certificate of
                    Incorporation of the Buyer, as amended or the By-laws of the
                    Buyer, as amended, (y) of law, any order of any court or
                    other agency of government, or (z) of any indenture,
                    agreement or other instrument to which the Buyer or any of
                    its properties or assets is bound, or conflict with, result
                    in a breach of or constitute (with due notice or lapse of
                    time or both) a default under any such indenture, agreement
                    or other instrument, or result in the creation or imposition
                    of any lien, charge, restriction, claim or encumbrance of
                    any nature whatsoever upon any of the properties or assets
                    of the Buyer, it being understood that, in connection with
                    the transactions contemplated by this Agreement and the
                    Merger Agreement, the parties will make all requisite
                    filings and otherwise comply with the applicable
                    requirements of (i) the HSR Act, (ii) the Exchange Act and
                    the Securities Act, (iii) state securities, takeover or blue
                    sky laws, and (iv) any other laws or regulations.

                         (c) Binding Agreement. This Agreement has been duly
                    executed and delivered by the Buyer and, assuming the due
                    execution and delivery by the other parties hereto,
                    constitutes the legal, valid and binding obligation of the
                    Buyer enforceable in accordance with its terms.

                                   ARTICLE IV

                                    COVENANTS

          Section 4.1 Irrevocable Proxy. NRG hereby irrevocably appoints the
     Buyer, or any

<PAGE>   11

     designee of the Buyer, with full power of substitution the lawful agent,
     attorney and proxy of NRG, from the date hereof until the Effective Date or
     unless this Agreement is terminated pursuant to Article XI hereof, at any
     meeting of the stockholders of Cogen, however called, or in connection with
     any written consent of the stockholders of Cogen (including the right to
     sign its name (as a stockholder) to any consent, certificate or other
     document relating to Cogen that the law of the State of Delaware may permit
     or require), to vote (or cause to be voted) the shares of common stock of
     Cogen held of record or beneficially by NRG (i) in favor of the Merger, the
     execution and delivery by Cogen of the Merger Agreement and any amendments
     thereto (so long as any such amendment does not materially adversely affect
     NRG) and the approval of the terms thereof, the amendment of the Cogen
     certificate of incorporation as provided in the Merger Agreement, and each
     of the other actions contemplated by this Agreement and the Merger
     Agreement, and any amendments hereto or thereto, with NRG's consent
     pursuant to the terms of this Agreement, and any actions required in
     furtherance hereof and thereof, (ii) against any proposal for any
     recapitalization, merger, sale of assets or other business combination
     between Cogen and any Person (other than the Merger) or any other action or
     agreement that would result in a breach of any covenant, representation or
     warranty or any other obligation or agreement of Cogen under the Merger
     Agreement or this Agreement, (iii) against any of the following actions
     (other than the transactions contemplated by the Merger Agreement): (1) any
     extraordinary corporate transaction, such as a merger, consolidation or
     other business combination involving Cogen or any of its Subsidiaries; (2)
     a sale, lease or transfer of a material amount of assets of Cogen or any of
     its Subsidiaries or a reorganization, recapitalization, dissolution or
     liquidation of Cogen of any of its Subsidiaries; (3) (a) any change in the
     majority of Cogen's board of directors; (b) any material change in the
     present capitalization of Cogen or any amendment to Cogen's certificate of
     incorporation (other than such amendment contemplated in connection with
     the Merger); or (c) any other change in Cogen's corporate structure or
     business; or (4) any other action which, is intended, or could reasonably
     be expected, to impede, interfere with, delay, postpone, discourage or
     adversely affect the Merger or the transactions contemplated by this
     Agreement or the contemplated economic benefits of any of the foregoing, or
     impede, interfere with, delay, postpone, discourage or adversely affect the
     Merger or the transactions contemplated by this Agreement. NRG further
     agrees to cause its shares of common stock of Cogen that are outstanding
     and owned by it beneficially to be voted in accordance with the foregoing.
     NRG agrees that it shall not enter into any agreement, arrangement or
     understanding with any Person the effect of which would be inconsistent
     with or violate the provisions of this Section 4.1. NRG intends this proxy
     to be irrevocable and coupled with an interest and will take such further
     action or execute such other instruments as may be necessary to effectuate
     the intent of this proxy and hereby revokes any proxy previously granted by
     it with respect to its shares of common stock of Cogen. NRG shall not,
     hereafter, unless and until this Agreement terminates pursuant to the terms
     hereof, purport to vote (or execute a consent with respect to) its shares
     of common stock of Cogen (other than through this irrevocable proxy) or
     grant any other proxy or power of attorney with respect to any such shares,
     deposit such shares into a voting trust or enter into any agreement (other
     than this Agreement), arrangement or understanding with any Person,
     directly or indirectly, to vote, grant any proxy or give instructions with
     respect to the voting of such shares.

                    Section 4.2 Additional Covenants.

                         (a) Cooperation. Prior to the Effective Date, each of
                    the Stockholders shall use its reasonable efforts to take
                    all actions and to do all things necessary, proper or
                    advisable in order to permit the consummation of the Merger.
                    The Buyer shall not cause the Merger Agreement to be amended
                    or consent to any proposed amendment of the Merger
                    Agreement, or waive any of its rights thereunder, in any way
                    that would be materially adverse to NRG, without NRG's prior
                    written consent.

                         (b) Operation of Business. Each of the Stockholders

<PAGE>   12

                    acknowledges that the Company is formed solely for the
                    purpose of effectuating the transactions contemplated by
                    this Agreement and the Merger Agreement. The Company shall
                    not transact any business whatsoever during the period
                    commencing on the date hereof and continuing through the
                    Effective Date other than in furtherance of the transactions
                    contemplated by this Agreement or the Merger Agreement.

                         (c) Dividend Policy. Beginning on the fourth
                    anniversary of the Effective Date, the Stockholders will
                    cause the Company to adopt appropriate policies of declaring
                    dividends at the highest level permitted by applicable law,
                    consistent with prudent business practices and having due
                    regard for relevant business, taxation, working capital,
                    financial covenant and operational requirements.


                         (d) Securities Filings. Each of the Buyer, the Company
                    and NRG shall promptly provide to any other party any
                    information requested for the purpose of preparing any
                    filings required to be filed with the Commission pursuant to
                    Sections 13d and 13e of the Exchange Act, and the rules and
                    regulations promulgated thereunder, in connection with this
                    Agreement or the Merger Agreement and the transactions
                    contemplated hereby and thereby.

                         (e) No Solicitation. Neither NRG nor any officer,
                    director, employee, representative or agent of NRG shall,
                    directly or indirectly, solicit, encourage, facilitate,
                    participate in or initiate any discussions or negotiations
                    regarding, or furnish to any Person any information with
                    respect to, or take any other action to facilitate any
                    inquiries or the making of any submission or proposal by any
                    Person (other than the Buyer) which constitutes, or may
                    reasonably be expected to lead to, (a) any sale of shares of
                    common stock of Cogen owned by NRG or (b) any Takeover
                    Proposal or Superior Proposal (as such terms are defined in
                    the Merger Agreement) or any agreement with respect thereto.
                    If NRG, or any officer, director, employee, representative
                    or agent of NRG, receives an inquiry or proposal with
                    respect to the sale of shares of common stock of Cogen, any
                    Takeover Proposal or any inquiry with respect to or which
                    could lead to any sale of shares of its common stock of
                    Cogen or any Takeover Proposal, then NRG shall advise the
                    Buyer orally (within one business day) and in writing (as
                    promptly as practicable) of the terms and conditions, if
                    any, of such inquiry or proposal and the identity of the
                    Person making it. NRG shall, and shall cause its officers,
                    directors, employees, representatives and agents to,
                    immediately cease and cause to be terminated any existing
                    activities, discussions or negotiations with any parties
                    conducted heretofore with respect to any of the foregoing.
                    This Section 4.2(e) will bind or apply to any Person except
                    in his or her capacity as a director of Cogen (or as an
                    officer of Cogen acting at the direction of Cogen's board of
                    directors) under applicable law and fiduciary duties, in
                    which case his or her actions shall be restricted solely by
                    the terms of the Merger Agreement.

                         (f) Restrictions on Transfer, Proxies and
                    NonInterference. Prior to the Effective Date, NRG hereby
                    agrees, except as contemplated hereby, not to (i) acquire,
                    sell, transfer, pledge, encumber, assign or otherwise
                    dispose of, or enter into any contract, option or other
                    arrangement or understanding with respect to the
                    acquisition, sale, transfer, pledge, encumbrance, assignment
                    or

<PAGE>   13

                    other disposition of, any shares of common stock of Cogen,
                    (ii) grant any proxies, deposit any of its shares of common
                    stock of Cogen into a voting trust or enter into a voting
                    agreement with respect to any of its shares of common stock
                    of Cogen, or (iii) take any action that would make any
                    representation or warranty of NRG contained herein untrue or
                    incorrect or have the effect of preventing or disabling NRG
                    from performing its obligations under this Agreement. NRG
                    agrees to notify the Buyer promptly and to provide all
                    details requested by the Buyer if NRG shall be approached or
                    solicited, directly or indirectly, by any Person with
                    respect to any of the foregoing.

                         (g) Stop Transfer Order. In furtherance of this
                    Agreement, concurrently with the execution of this
                    Agreement, NRG shall and hereby does authorize Cogen's
                    counsel to notify Cogen's transfer agent that there is a
                    stop transfer order with respect to all of NRG's shares of
                    common stock of Cogen (and that this Agreement places limits
                    on the voting and transfer of such shares).

                         (h) Cooperation on Regulatory Matters. If so requested
                    by the Buyer, promptly after the date hereof, NRG will use
                    its reasonable best efforts to cause it and Cogen (if
                    required) to make all filings which are required under the
                    HSR Act and applicable requirements and to seek all
                    regulatory approvals required in connection with the
                    transactions contemplated hereby and by the Merger
                    Agreement. The parties shall furnish to each other such
                    necessary information and reasonable assistance as may be
                    requested in connection with the preparation of filings and
                    submissions to any governmental agency, including, without
                    limitation, filings under the provisions of the HSR Act. NRG
                    shall also use its reasonable efforts to cause Cogen to
                    supply the Buyer with copies of all correspondence, filings
                    or communications (or memoranda setting forth the substance
                    thereof) between Cogen and its representatives and the
                    Federal Trade Commission, the Department of Justice and any
                    other governmental agency or authority and members of their
                    respective staffs with respect to this Agreement and the
                    transactions contemplated hereby.

                                    ARTICLE V

                            ADDITIONAL CONTRIBUTIONS
<PAGE>   14

         Section 5.1. Additional Capital Contributions. Immediately prior to the
Effective Date, but after an affirmative vote of Cogen's stockholders approving
the Merger Agreement has been duly taken and recorded, the Buyer and NRG shall
make contributions of capital to the Company as set forth below, it being
understood that all such contributions shall be made simultaneously (the date of
such contributions being referred to herein as the "Contribution Date"):

                         (a) Obligations of NRG. NRG shall contribute to the
                    Company that number of shares of common stock of Cogen that
                    have, in the aggregate, a value (based on a $25.00 per share
                    value) equal to (i) 20% of the Total Equity Value of the
                    Company, as hereinafter defined, less (ii) the Adjustment
                    Amount, as hereinafter defined, in exchange for such number
                    of shares of Common Stock as would result in NRG holding 20%
                    of the issued and outstanding shares of Common Stock. "Total
                    Equity Value of the Company" means the sum of (i) an amount
                    determined by multiplying (A) the total number of issued and
                    outstanding shares of common stock of Cogen by (B) $25.00
                    (the "Merger Price") and (ii) the aggregate amount of the
                    excess of the Merger Price over the exercise price of each
                    of the outstanding options set forth on Schedule 1 hereto
                    which are currently exercisable or will become exercisable
                    upon consummation of the Transactions (as defined in the
                    Merger Agreement). "Adjustment Amount" means an amount
                    determined by multiplying (i) the total number of shares
                    underlying the Cancelled Options, as hereinafter defined, by
                    (ii) the excess of the Merger Price over the exercise price
                    for each Cancelled Option. "Cancelled Options" means those
                    options owned by David H. Peterson, Ronald J. Will and Craig
                    A. Mataczynski listed on Schedule 1 to this Agreement,
                    which, on or before the Merger Date, have been cancelled for
                    no consideration and a termination agreement as contemplated
                    in the Merger Agreement has been signed and provided to the
                    Buyer. NRG represents that if such contribution were made on
                    the date hereof and assuming that Cancelled Options includes
                    all options held by David H. Peterson, Ronald J. Will and
                    Craig A. Mataczynski, it would be obligated to contribute to
                    the Company 1,394,973 shares of common stock of Cogen to the
                    Company. NRG may, at its sole option, contribute to the
                    Company additional shares of common stock of Cogen; provided
                    that it shall own 20% of the Common Stock and shall receive
                    no additional consideration in respect of any additional
                    capital contribution of shares of common stock of Cogen to
                    the Company.

                         (b) Obligations of the Buyer. The Buyer shall
                    contribute to the Company cash in an amount equal to 80% of
                    the Total Equity Value of the Company in exchange for such
                    number of shares of Common Stock as would result in the
                    Buyer holding 80% of the issued and outstanding shares of
                    Common Stock. The Buyer represents that if such contribution
                    were made on the date hereof, it would be obligated to
                    contribute $146,539,730, as appropriately adjusted to the
                    extent of any contribution by NRG under the last sentence of
                    Section 5.1(a) above. The requisite cash contribution by the
                    Buyer shall be made in immediately available funds.

                    Additionally, the Buyer will contribute to the Company, in
                    the form a loan pursuant to a Promissory Note in the form
                    attached hereto as Exhibit E, in an original principal
                    amount not less than (i) the amount necessary to repay in
                    full the debt of Cogen listed on Schedule 2 hereto, (ii) the
                    amount necessary to

<PAGE>   15

                    satisfy all other obligations of the Company under this
                    Agreement and the Merger Agreement or any other document
                    related hereto or thereto, and (iii) transaction costs of
                    the Company associated with the transactions contemplated by
                    this Agreement and the Merger Agreement. The Buyer agrees
                    that it shall not consummate the Merger without either (i)
                    causing the outstanding indebtedness of Cogen's Subsidiaries
                    to be refinanced on the substantially the same terms as the
                    Promissory Note in the form attached hereto as Exhibit E;
                    provided, however, that NRG shall have the option to
                    participate in any such refinancing pro rata according to
                    its ownership of the Company or (ii) obtaining consent of
                    the lenders of Cogen's Subsidiaries to the transactions
                    contemplated by the Merger Agreement or this Agreement.

                  Section 5.2 NRG's Obligation to Contribute Shares. In no event
shall NRG be obligated to contribute its shares of common stock of Cogen
pursuant to Section 5.1(a) unless (i) Cogen's stockholders have duly approved
the Merger Agreement and (ii) all of the conditions to closing set forth in the
Merger Agreement have been satisfied or waived.

                  Section 5.3 The Buyer's Obligation to Contribute Cash. In no
event shall the Buyer be obligated to contribute cash pursuant to Section 5.1(b)
above unless all of the conditions to closing set forth in the Merger Agreement
have been satisfied or waived.

                                   ARTICLE VI

                 MANAGEMENT OF THE COMPANY FOLLOWING THE MERGER

                  Section 6.1 Conduct of Business. (a) Notwithstanding the fact
that no vote may be required or that a lesser percentage vote may be specified
by law, by the Certificate of Incorporation or the By-Laws, each as amended, by
any agreement with any national securities exchange or otherwise, except as
hereinafter provided in this paragraph (a) or otherwise in this Agreement, as of
the date hereof, neither the Company nor its Subsidiaries shall take or permit
any of the following actions to be taken without the specific prior written
consent of NRG (which, at the direction of NRG, may be effectuated by the NRG
Director), except as otherwise contemplated by Article VIII or in any other
provision of this Agreement:

                                    (i) The issuance, repurchase, exchange or
                        redemption of any Shares of any Capital Stock (including
                        any Common Stock), or the grant of the right or option
                        to acquire any shares of such Capital Stock, of the
                        Company.

                                    (ii) Any sale or disposition of any of the
                        Company's Subsidiaries and, other than in the ordinary
                        course of business, the sale or disposition of property
                        or assets of the Company or its Subsidiaries in excess
                        of 20% of the fair market value of the total assets of
                        the Company.

                                    (iii) Any amendment, modification or
                        supplement to, or repeal of, or adoption of any policy
                        or procedures inconsistent with, any provision of the
                        Certificate of Incorporation or By-Laws; provided, that,
                        the Company may amend the Certificate of Incorporation
                        to effect a change of name or a change of registered
                        agent for service of process
<PAGE>   16
                        without NRG's prior written consent.

                                    (iv) Any merger, consolidation or other
                        business combination of the Company with any other
                        Person except for any merger or consolidation involving
                        any direct or indirect Wholly-Owned Subsidiary of the
                        Company and except for the Merger.

                                    (v) The authorization or entering into by
                        the Company or any of its Subsidiaries of any contract,
                        agreement, transaction or other arrangement or any
                        modification, waiver or amendment to any of the
                        foregoing, with any of the Buyer or its Affiliates with
                        a value (or obligation on the part of the Company or
                        such Subsidiary) in excess of $2,000,000; provided that
                        the Company or its Subsidiaries may enter into (x)
                        contracts, agreements, transactions or other
                        arrangements or modifications, waivers or amendments to
                        the foregoing with any of the Buyer or its Affiliates
                        with a value (or obligation on the part of the Company
                        or such Subsidiary) in excess of $2,000,000 if the terms
                        and provisions thereof are no less favorable to the
                        Company or such Subsidiary than those that would be
                        available in a comparable arms-length transaction and
                        the Buyer shall have certified the same to the Board of
                        Directors prior to the entry into or execution of the
                        same, and (y) the Merger Agreement and any of the
                        transactions or documents contemplated by the Merger
                        Agreement.

                                    (vi) The appointment or renewal of the
                        Company's independent auditor if such auditor is not the
                        Buyer's independent auditor, or any change in accounting
                        periods or the accounting principles under which the
                        Company's financial statements are presented except as
                        may be required by GAAP or as are consistent with
                        accounting principles used by the Buyer as of the date
                        of this Agreement.

                                    (vii) (a) the dissolution of the Company or
                        any of its Subsidiaries, or the commencing of the
                        process of dissolution; (b) the adoption of a plan of
                        liquidation of the Company or any of its Subsidiaries;
                        and (c) any action by the Company or any of its
                        Subsidiaries to commence any suit, case, proceeding or
                        other action (1) under the Bankruptcy Code or any other
                        existing or future law of any jurisdiction relating to
                        bankruptcy, insolvency, reorganization or relief of
                        debtors seeking to have an order for relief entered with
                        respect to it, or seeking to adjudicate it bankrupt or
                        insolvent, or seeking reorganization, arrangement,
                        adjustment, winding-up, liquidation, dissolution,
                        composition or other relief with respect to it, or (2)
                        seeking appointment of a receiver, trustee, custodian,
                        or other similar official for it or for all or any
                        substantial part of its assets or making a general
                        assignment

<PAGE>   17

                        for the benefit of its creditors.

                                    (viii) The issuance of any liquidating
                        distributions to the Stockholders.

                    (b) The Stockholders shall take no action that would have
               the effect of causing the Company to contravene any provision of
               this Section 6.1.

                    (c) Notwithstanding any provision in Section 6.1(a)(v), the
               parties agree that the Buyer and/or its designated Affiliates
               shall be permitted to enter into (i) Operating and Maintenance
               Agreements with the Company or its Subsidiaries in substantially
               the respective forms of such agreements existing on the date
               hereof between NRG and its Affiliates, on one hand, and Cogen's
               Subsidiaries, on the other hand, (ii) a Management
               Services Agreement, an Operating and Maintenance Agreement for
               the Pryor project and Energy Services Agreements in substantially
               the respective forms agreed to by the parties on the date hereof,
               and (iii) a Tax Sharing Agreement in substantially the form
               agreed to by the parties on the date hereof.

                                   ARTICLE VII

                           TRANSFERS OF CAPITAL STOCK

         Section 7.1 Restrictions on Transfer. Each Stockholder agrees that
during the Restricted Period, such Stockholder will not offer, sell, transfer,
assign or otherwise dispose of (or make any exchange, gift, assignment or pledge
of or impose any lien or encumbrance on) (collectively, for purposes of Sections
7 and 8 hereof only, a "Transfer") any of its shares of Common Stock, or
options, warrants or rights to subscribe for or purchase shares of Common Stock,
without the prior written consent of all the Stockholders, which consent shall
not be unreasonably withheld or delayed. For purposes of this Section 7.1, a
merger or consolidation or other business combination or any change in control
of the Buyer or the ultimate parent company of NRG will not be deemed to be a
Transfer.

         Section 7.2 Exceptions to Restrictions. The provisions of Section 7.1
and Section 8 shall not apply to any of the following transfers:

                    (a) From any Stockholder to any Wholly-Owned Subsidiary of
               any Stockholder or any Person which owns 100% of the Capital
               Stock of any Stockholder (each a "Permitted Transferee"),
               provided that each such Permitted Transferee shall execute a
               counterpart of and become a party to this Agreement and shall
               agree in a writing in form and substance satisfactory to the
               Company to be bound and becomes bound by the terms of this
               Agreement.

                    (b) Pursuant to a permitted merger or consolidation
               involving the Company or any of its Subsidiaries.

         Section 7.3 Applicability. The provisions of this Agreement shall be
applied to the shares of Common Stock acquired by any Permitted Transferee of a
Stockholder in the same manner and to the same extent as such provisions were
applicable to such Common Stock in the hands of such Stockholder.

         Section 7.4 Endorsement of Certificates.



<PAGE>   18

                         (a) Upon the execution of this Agreement, in addition
                    to any other legend that the Company may deem advisable
                    under the Securities Act and certain state securities laws
                    or required pursuant to the Company's Certificate of
                    Incorporation or By-Laws, all certificates representing
                    issued and outstanding shares of Common Stock that are
                    subject to any of the provisions of this Agreement shall be
                    endorsed as follows:

                    THE SECURITIES EVIDENCED BY THIS CERTIFICATE ARE SUBJECT TO,
                    AND ARE TRANSFERABLE ONLY UPON COMPLIANCE WITH, THE
                    PROVISIONS OF A STOCKHOLDERS AGREEMENT DATED AS OF AUGUST
                    26, 1999, AMONG THE COMPANY AND ITS STOCKHOLDERS. A COPY OF
                    THE ABOVE-REFERENCED AGREEMENT IS ON FILE AT THE PRINCIPAL
                    OFFICE OF THE COMPANY. NO REGISTRATION OF TRANSFER OF SUCH
                    SECURITIES WILL BE MADE ON THE BOOKS OF THE COMPANY UNLESS
                    AND UNTIL SUCH RESTRICTIONS SHALL HAVE BEEN COMPLIED WITH.

                    THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                    REGISTERED UNDER THE SECURITIES ACT OF 1933 AND MAY NOT BE
                    SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT,
                    OR AN EXEMPTION FROM REGISTRATION, UNDER SAID ACT.

                         (b) Except as otherwise expressly provided in this
                    Agreement, all certificates representing shares of Common
                    Stock hereafter issued to or acquired by any of the
                    Stockholders or their successors or assigns (including,
                    without limitation, all certificates representing shares of
                    Common Stock hereafter issued upon conversion of shares of
                    Common Stock of any other class) shall bear the legends set
                    forth above, and the shares of stock represented by such
                    certificates shall be subject to the applicable provisions
                    of this Agreement. The obligations of each party hereto
                    shall be binding upon each transferee to whom shares of
                    Common Stock are Transferred by any party hereto, whether or
                    not such Transfer is permitted under the terms of this
                    Agreement. Prior to consummation of any Transfer, such
                    Stockholder shall cause the Transferee to execute an
                    agreement in form and substance reasonably satisfactory to
                    the other Stockholders hereto, providing that such
                    Transferee shall fully comply with the terms of this
                    Agreement. Prompt notice shall be given to the Company and
                    each Stockholder by the transferor of any Transfer (whether
                    or not to a Permitted Transferee) of any Common Stock.

         Section 7.5 Improper Transfer. Any attempt to Transfer or encumber any
shares of Common Stock other than in accordance with the terms of this Agreement
shall be null and void and neither the Company nor any transfer agent of such
securities shall give any effect to such attempted Transfer or encumbrance in
its stock records.

                                  ARTICLE VIII

                   RIGHTS OF FIRST REFUSAL; DRAG-ALONG RIGHTS;
                        TAG-ALONG RIGHTS; PURCHASE OPTION
<PAGE>   19

                    Section 8.1. Right of First Refusal.

                         (a) Except for (i) Transfers to a Permitted Transferee,
                    and (ii) transactions subject to Sections 8.2, 8.3, and 8.4,
                    if at any time after the Restricted Period NRG receives a
                    bona fide offer which NRG desires to accept (a "Transfer
                    Offer") to sell any shares of Common Stock (or options,
                    warrants or rights to subscribe for or purchase shares of
                    Common Stock) owned by it, then NRG shall cause the Transfer
                    Offer to be reduced to writing and shall deliver written
                    notice of such Transfer Offer (a "Transfer Notice"),
                    accompanied by a copy of such Transfer Offer to the Buyer
                    and the Company, setting forth the identity of the offeror,
                    the number and class of shares of Common Stock (or options,
                    warrants or rights) proposed to be transferred (the "Offered
                    Securities"), the price per security contained in the
                    Transfer Offer (the "Transfer Offer Price Per Security"),
                    and all other terms applicable thereto. The Transfer Notice
                    shall also contain an irrevocable offer to sell the Offered
                    Securities to the Buyer at a price equal to the Transfer
                    Offer Price Per Security and upon substantially the same
                    terms as contained in the Transfer Offer. In the event that
                    the form of consideration specified in the Transfer Offer is
                    other than cash, NRG shall use its best efforts to cause the
                    consideration of such Transfer Offer to be reduced to cash.
                    In the event that NRG is unsuccessful in obtaining a
                    Transfer Offer with cash consideration, NRG shall not accept
                    such Transfer Offer.

                                                (i) Upon receipt of the Transfer
                                    Notice, the Buyer shall then have the right
                                    to accept such offer at the Transfer Offer
                                    Price Per Security and on the other terms
                                    specified in the Transfer Offer with respect
                                    to all, but not less than all, of the
                                    Offered Securities. The rights of the Buyer
                                    pursuant to this clause (ii) shall be
                                    exercisable by the delivery of notice to NRG
                                    (the "Notice of Exercise") (a copy of which
                                    shall also be delivered to the Company)
                                    within 30 business days from the date of
                                    delivery of the Transfer Notice, which
                                    Notice of Exercise shall be deemed an
                                    irrevocable acceptance of the Transfer
                                    Offer.

                                                (ii) In the event that the Buyer
                                    exercises its rights to purchase all the
                                    Offered Securities in accordance with clause
                                    (i) above, then NRG must sell such Offered
                                    Securities to the Buyer, at the Transfer
                                    Offer Price Per Security and on the

<PAGE>   20
                                    other terms specified in the Transfer Offer.

                         (b) If all notices required to be given pursuant to
                    Section 8.1(a) have been duly given and the Buyer does not
                    purchase the Offered Securities pursuant to the provisions
                    hereof, then NRG shall have the right, subject to compliance
                    by NRG with the provisions of Section 7.4(b) hereof, from
                    the date which is the earlier of (i) the expiration of the
                    option period pursuant to Section 8.1(a) or (ii) the date on
                    which NRG receives notice from the Buyer that it will not
                    exercise the option granted pursuant to Section 8.1(a), to
                    sell to such Person which originally made the Transfer Offer
                    the Offered Securities at a price per Offered Security equal
                    to or greater than 100% of the Transfer Offer Price Per
                    Security and on the other terms specified in the Transfer
                    Offer.

                         (c) The consummation of any purchase and sale pursuant
                    to Section 8.1(a) shall take place on such date, not later
                    than 60 calendar days after the expiration of the option
                    period pursuant to Section 8.1(a), as the purchaser shall
                    select. Upon the consummation of any such purchase and sale,
                    NRG shall deliver certificates representing the Offered
                    Securities sold duly endorsed, or accompanied by written
                    instruments of transfer in form satisfactory to the
                    purchaser duly executed by NRG free and clear of any liens,
                    against delivery of the Transfer Offer Price Per Security
                    for each of the Offered Securities purchased by federal
                    funds wired to such bank or financial institution specified
                    in writing by NRG. If the purchase and sale is not
                    consummated within the 60 calendar day period referred to in
                    this subsection (c), then the provisions of Section 8.1
                    shall again apply to such shares.

                  Section  8.2.     Drag-Along.

                         (a) Subject to any approval or other rights in this
                    Agreement, if after the expiration of the Restricted Period,
                    the Buyer sells all or substantially all the Fully Diluted
                    Common Stock owned by it (whether pursuant to a sale, merger
                    or other consolidation, a "Company Sale") in a bona fide
                    arm's-length transaction to a third party that is not an
                    Affiliate of the Buyer or of the Company (an "Independent
                    Third Party"), then the Buyer shall have the right, subject
                    to all the provisions of this Section 8.2 ("Drag-Along
                    Right"), to require NRG to (i) if such Company Sale is
                    structured as a sale of stock, sell, transfer and deliver or
                    cause to be sold, transferred and delivered to such
                    Independent Third Party all shares of Fully Diluted Common
                    Stock, owned or held by it or (ii) if such Company Sale
                    requires the consent or approval of the Company's
                    stockholders, vote NRG's shares of Common Stock in favor
                    thereof, and, in any such event, except to the extent
                    otherwise provided in subsection (c) of this Section 8.2,
                    NRG shall agree to and shall be bound by the same terms,
                    provisions and conditions in respect of the Company Sale as
                    are applicable to the Buyer. The provisions of Section 8.1
                    shall not apply to any transactions to which this Section
                    8.2

<PAGE>   21
               applies.

                    (b) If the Buyer desires to exercise its Drag-Along Rights,
               it shall give written notice to the other Stockholder
               ("Drag-Along Notice") of the Company Sale, setting forth the name
               and address of the transferee, the date on which such transaction
               is proposed to be consummated (which shall be not less than 30
               days after the date such Drag-Along Notice is given), and the
               proposed amount of cash consideration and terms and conditions of
               payment offered by such transferee.

                    (c) The obligations of the Stockholders in respect of a
               Company Sale under this Section 8.2 are subject to the
               satisfaction of the following conditions: (i) subject to (v)
               below, upon the consummation of the Company Sale, consideration
               of equivalent value in cash or Cash Equivalents realized upon
               such Company Sale shall be paid or distributed in respect of each
               share of Common Stock then issued and outstanding; (ii) each
               holder of then currently exercisable rights to acquire shares of
               Common Stock will be given a reasonable opportunity to exercise
               such rights prior to the consummation of the Company Sale and
               thereby to participate in such sale as a holder of such Common
               Stock; (iii) there shall be no liability of NRG for
               indemnification in respect of any matters arising pursuant to or
               in connection with the Company Sale, other than with respect to
               NRG's ownership of its shares of Common Stock; (iv) NRG shall not
               be required to make general representations or warranties
               regarding the financial condition, business, assets or affairs of
               the Company and its Subsidiaries; (v) the valuation of NRG's
               shares of Common Stock shall take into account not only the
               consideration received by the Buyer for its Common Stock but also
               any consideration received by the Buyer or its for the sale,
               transfer or disposition of any ownership or other interests,
               contract rights, permits or any other asset of the Buyer or its
               Affiliates with respect to its investment in the Company related
               to or contemplated by the sale of the Buyer's Common Stock; and
               (vi) NRG shall be given a reasonable opportunity to review and
               provide comments to the agreements or documents relating to the
               Company Sale.


<PAGE>   22




         Section 8.3       Tag-Along Rights.

                        (a) Notwithstanding anything in this Agreement to the
                  contrary, except in the case of (i) transfers to a Permitted
                  Transferee referred to in Section 7.2 and (ii) transactions
                  subject to Section 8.2, the Buyer shall not sell, dispose of
                  or otherwise transfer any shares of Common Stock, options,
                  warrants or rights to subscribe for or purchase shares of
                  Common Stock, unless, prior to the consummation thereof, NRG
                  shall have been afforded the opportunity to join in such sale
                  with respect to all of the shares of Common Stock owned by
                  NRG, as hereinafter provided in this Section 8.3.

                        (b) Prior to consummation of any proposed sale,
                  disposition or transfer of shares of Common Stock (or options,
                  warrants or rights) described in Section 8.3(a), the Buyer
                  (the "Disposing Stockholder") shall cause the person or group
                  that proposes to acquire such shares (the "Proposed
                  Purchaser") to offer NRG in writing ("Purchase Offer") the
                  right to sell all of the shares of Common Stock (or options,
                  warrants or rights) owned by NRG. The Purchase Offer shall be
                  accompanied by a copy of the Proposed Purchaser's final offer
                  to the Disposing Stockholder. If the Purchase Offer is
                  accepted by NRG, then the number of shares of Common Stock (or
                  options, warrants or rights) to be sold to the Proposed
                  Purchaser by the Disposing Stockholder shall be reduced by the
                  aggregate number of shares of Common Stock (or options,
                  warrants or rights) to be purchased by the Proposed Purchaser
                  from NRG pursuant thereto. Such purchase shall be made on the
                  same terms and conditions as the Proposed Purchaser shall have
                  offered to purchase shares of Common Stock to be sold by the
                  Disposing Stockholder (net, in the case of any options,
                  warrants or rights, of any amounts required to be paid by the
                  holder upon exercise thereof); provided, however, that the
                  valuation of NRG's Common Stock shall take into account not
                  only the consideration received by the Buyer for its Common
                  Stock but also only consideration received by the Buyer or its
                  Affiliates for the sale, transfer or disposition of any
                  ownership or other interests, contract rights, permits or any
                  other asset of the Buyer or its Affiliates with respect to its
                  investment in the Company related to or contemplated by the
                  sale of the Buyer's Common Stock. NRG shall have 30 days from
                  the date of receipt of the Purchase Offer during which to
                  accept such Purchase Offer, and the closing of such purchase
                  shall occur within 30 days after such acceptance or at such
                  other time as NRG and the Proposed Purchaser may agree.


<PAGE>   23



                        Section 8.4 Purchase Option.

                              (a) The Buyer shall, for a period of 365 days
                        commencing on the day after the expiration of the
                        Restricted Period (the "Option Period"), have the option
                        to acquire from NRG all, but not less than all, of the
                        shares of Common Stock held by NRG (the "Option").

                              (b) In the event that the Buyer determines that it
                        may exercise the Option, it shall, at any time during
                        the Option Period or within the 60 days prior to the
                        commencement of the Option Period, give notice to NRG
                        that it intends to obtain a fair market value
                        determination pursuant to this Section 8.4 (the
                        "Valuation Notice"). The fair market value of the
                        Company shall be determined by one nationally recognized
                        and independent investment bank mutually acceptable to
                        NRG and the Buyer (the "Valuing Investment Bank"), it
                        being understood that for the purpose of this Section
                        8.4 an independent investment bank shall be one which is
                        neither affiliated with nor employed as the primary
                        investment banking firm of NRG, the Buyer or the
                        Company. The Buyer shall include in its Valuation Notice
                        a list of at least three (3) investment banks acceptable
                        to the Buyer as the Valuing Investment Bank and
                        satisfying the criteria set forth in the preceding
                        sentence. Upon receipt of such list, NRG shall promptly
                        notify the Buyer which of such investment banks, if any,
                        is acceptable to it. If NRG rejects each such investment
                        bank as unacceptable to it, NRG shall promptly notify
                        the Buyer of the identity of at least three investment
                        banks acceptable to NRG and satisfying the criteria set
                        forth in the second sentence of this paragraph. Upon
                        receipt of such notice, the Buyer shall promptly notify
                        NRG which of such investment banks, if any, is
                        acceptable to it. NRG and the Buyer shall each act with
                        such promptness and diligence that the procedures
                        described in the foregoing sentences will result in the
                        selection of a Valuing Investment Bank in as short a
                        period of time as practicable. NRG and the Buyer shall
                        each be responsible for 50% of the total fees and
                        expenses charged by the Valuing Investment Bank;
                        provided, however, in the event that the Buyer does not
                        exercise the Option, the Buyer shall be responsible for
                        100% percent of the total fees and expenses charged by
                        the Valuing Investment Bank.

                              (c) The Valuing Investment Bank may use, among
                        other methodologies, discounted cash flow, comparable
                        transaction and traded company analyses to determine the
                        fair market value of the Company. In determining the
                        fair market value of the Company, the Valuing Investment
                        Bank shall evaluate the Company (i) without any
                        consideration of the
<PAGE>   24
                        management fee to be paid to the Buyer under Section
                        9.3, (ii) without factoring in any discount arising from
                        NRG's minority ownership position and limited
                        representation on the Company's Board of Directors, and
                        (iii) without any consideration of any discount
                        applicable to an initial Public Offering. Moreover, to
                        the extent that, as of the time of the valuation
                        determination, financing for the Company or its
                        Subsidiaries or their generation assets is available
                        under terms more favorable than those terms in place,
                        the more favorable financing terms shall be utilized by
                        the Valuing Investment Bank in its fair market value
                        determination; provided, however, that to the extent the
                        financing for any of the Subsidiaries at the time of
                        such valuation is on substantially the same material
                        economic terms as the financing for such Subsidiary on
                        the date hereof, such financing terms shall be utilized
                        by the Valuing Investment Bank in its fair market value
                        determination.

                              (d) In the event that the Buyer wishes to exercise
                        the Option, the aggregate price payable to NRG for its
                        Common Stock (the "Option Price") shall be equal to
                        NRG's Pro Rata Portion of the fair market value of the
                        Company (on a consolidated basis) as determined by the
                        Valuing Investment Bank pursuant to Section 8.4(c)
                        above. The Buyer shall exercise the Option by providing
                        written notice to NRG prior to the expiration of the
                        Option Period, which notice shall be irrevocable.

                  Section 8.5 Waiver. For purposes of this Article VIII, any
Person who has failed to give notice of the election of an option hereunder
within the specified time period will be deemed to have waived its rights with
respect thereto on the day immediately following the last day of such period.

                                   ARTICLE IX

                               CERTAIN AGREEMENTS

                  Section 9.1. Access to Information Regarding Subsidiaries. The
Buyer and the Company shall cause the NRG Director to be provided with all
material information regarding the Company's Subsidiaries, including without
limitation their respective business, operations, property, assets, condition
(financial or otherwise) or prospects thereof, and such other information
regarding the Company's Subsidiaries as the NRG Director, may reasonably
request. NRG shall at all times preserve in strict confidence all information of
a proprietary or confidential nature relating to the business of the Company and
which is acquired by virtue of this Agreement and shall use all such information
solely in connection with the monitoring of NRG's investment in the Company;
provided, that NRG shall be entitled to disclose any such information in
confidence to any of its professional advisors or publicly disclose such
information to the extent required by law, regulation or Commission filing.

                  Section 9.2. Financial Statements; Inspections.

                              (a) The Company and the Buyer shall provide NRG
                        with (i) the unaudited consolidated and consolidating
                        quarterly financial statements of the



<PAGE>   25

                        Company and each of its Subsidiaries for each calendar
                        quarter within 35 days of the end of such calendar
                        quarter, and (ii) the audited consolidated and
                        consolidating financial statements of the Company and
                        each of its Subsidiaries for each calendar year within
                        70 days after the end of each calendar year.

                              (b) NRG's independent auditors shall, for purposes
                        of certifying the financial statements of NRG and its
                        direct and indirect parents, have the right, upon
                        reasonable prior notice to the Company, to visit and
                        inspect the properties of the Company and its
                        Subsidiaries and to examine and copy (at NRG's own
                        expense) their books of record and accounts, and to
                        discuss their affairs, finances, and accounts with their
                        officers and their current and prior independent public
                        accountants, all at such times (during normal business
                        hours) as NRG may reasonably request. The foregoing
                        rights are in addition, and are not intended to limit,
                        any rights that NRG may have under the law of the State
                        of Delaware, including Sections 219 and 220 of the
                        Delaware General Corporation Law.

                  Section 9.3 Management Fee.

                              (a) The Company shall pay to the Buyer a
                        management fee (the "Management Fee") determined in
                        accordance with the provisions of this Section 9.3(a).
                        The Management Fee shall be determined in arrears
                        following each calendar year and shall be equal to the
                        amount, if any, by which Actual Adjusted Net Income for
                        the immediately preceding calendar year exceeds the
                        Projected Adjusted Net Income for such calendar year. No
                        Management Fee shall be payable with respect to the year
                        ending December 31, 1999.

                              "Actual Adjusted Net Income" shall mean, for any
                        period, the consolidated net income of the Company for
                        such period determined in accordance with GAAP
                        consistently applied, except that such amount shall be
                        (i) increased by the taxes that were deducted from
                        operating income to arrive at net income for such
                        period, (ii) adjusted to exclude any accrual made for
                        estimated management fees for such period, and (iii)
                        calculated without regard to any extraordinary items of
                        income or expense in such period or other transactions
                        not in the ordinary course of the Company's business in
                        such period.

                              "Projected Adjusted Net Income" shall mean, for
                        any period, the projected pre-tax net income for such
                        period set forth on Schedule 3 hereto, as amended with
                        respect to the line items indicated on Schedule 3, to
                        take account of the adjusted book basis amount and
                        depreciation amount for the applicable period set forth
                        on a schedule approved by the parties as soon as
                        reasonably practicable following the Effective Date.
                        Projected Adjusted Net Income with respect to the year
                        ending December 31, 2000 shall be pro-rated to the
                        extent the Effective Date occurs after December 31, 1999
                        (such pro-ration to be calculated on the basis of the
                        number of days after the Effective Date remaining in the
                        year divided by 365).

                              (b) Notwithstanding the foregoing, the obligations
                        of the Company to pay the Management Fee shall be null
                        and void and shall no longer apply to any calendar year
                        after the fourth anniversary of the Effective Date.


                                    ARTICLE X
<PAGE>   26

                               REGISTRATION RIGHTS

                  Section 10.1 Piggyback Registrations.

                              (a) In no event shall the Company register any of
                        its equity securities during the Restricted Period. If,
                        at any time after the fourth anniversary of the
                        Effective Date, the Company at any time proposes to
                        register any of its equity securities under the
                        Securities Act, whether or not for sale for its own
                        account, on a form and in a manner that would permit
                        registration of Registrable Securities for sale to the
                        public under the Securities Act, it will give written
                        notice to all the holders of Registrable Securities
                        promptly of its intention to do so, describing such
                        securities and specifying the form and manner and the
                        other relevant facts involved in such proposed
                        registration, including, without limitation, (x) the
                        intended method of disposition of the securities
                        offered, including whether or not such registration will
                        be effected through an underwriter in an underwritten
                        offering or on a "best efforts" basis, and, in any case,
                        the identity of the managing underwriter, if any, and
                        (y) the price at which the Registrable Securities are
                        reasonably expected to be sold. Upon the written request
                        of any holder of Registrable Securities delivered to the
                        Company within 30 calendar days after the receipt of any
                        such notice


<PAGE>   27



                        (which request shall specify the Registrable Securities
                        intended to be disposed of by such holder), the Company
                        will effect the registration under the Securities Act of
                        all the Registrable Securities that the Company has been
                        so requested to register; provided, however, that:

                                                     (i) if, at any time after
                                            giving such written notice of its
                                            intention to register any securities
                                            and prior to the effective date of
                                            the registration statement filed in
                                            connection with such registration,
                                            the Company shall reasonably
                                            determine not to register such
                                            securities, the Company may, at its
                                            election, give written notice of
                                            such determination to each holder of
                                            Registrable Securities who shall
                                            have made a request for registration
                                            as hereinabove provided and
                                            thereupon the Company shall be
                                            relieved of its obligation to
                                            register any Registrable Securities
                                            in connection with such registration
                                            (but not from its obligation to pay
                                            the Registration Expenses in
                                            connection therewith), without
                                            prejudice, however, to the right of
                                            any Person to request that such
                                            registration be effected as a
                                            registration under this Section
                                            10.1; and

                                                     (ii) if such registration
                                            involves an Underwritten Offering,
                                            all holders of Registrable
                                            Securities requesting to be included
                                            in the Company's registration must
                                            sell their Registrable Securities to
                                            the underwriters selected by the
                                            Company on the same terms and
                                            conditions as apply to the Company.

                              (b) The Company shall not be obligated to effect
                        any registration of Registrable Securities under this
                        Section 10.1 incidental to the registration of any of
                        its securities in connection with mergers, acquisitions,
                        exchange offers, dividend reinvestment plans or stock
                        option or other employee benefit plans.

                              (c) If a registration pursuant to this Section
                        10.1 involves an underwritten offering and the managing
                        underwriter advises the issuer that, in its opinion, the
                        number of securities proposed to be included in such
                        registration should be limited due to market conditions,
                        the Company will so advise each holder of Registrable
                        Securities that has requested registration pursuant to
                        Section 10.1(a), and shares shall be excluded from such
                        offering in the following order until such limitation
                        has been met: First, the Registrable Securities
                        requested to be included in such offering by a
                        Stockholder other than a NRG or any Permitted Transferee
                        of NRG


<PAGE>   28



                        shall be excluded pro rata, based on the respective
                        number of Registrable Securities as to which
                        registration has been so requested by such Stockholders,
                        until all such Registrable Securities shall have been so
                        excluded; second, the Registrable Securities requested
                        to be included in such offering by NRG or any Permitted
                        Transferee of NRG shall be excluded pro rata, based on
                        the respective number of Registrable Securities as to
                        which registration has been so requested by NRG or any
                        Permitted Transferee of NRG, until all such Registrable
                        Securities shall have been so excluded; and thereafter,
                        the securities requested to be registered by the Company
                        shall be excluded.

                              (d) In connection with any underwritten offering
                        with respect to which holders of Registrable Securities
                        shall have requested registration pursuant to this
                        Section 10.1, the Company shall have the right to select
                        the managing underwriter with respect to the offering;
                        provided that such managing underwriter shall be a
                        nationally recognized investment banking firm.

                              (e) The Company will pay all Registration Expenses
                        incurred in connection with each of the registrations of
                        Registrable Securities effected by it pursuant to this
                        Section 10.1.

                                   ARTICLE XI

                                   TERMINATION

                  Section 11.1. Termination.

                              (a) The provisions of this Agreement shall
                        terminate on the date on which any of the following
                        events first occurs: (i) an initial Public Offering or,
                        (ii) the Merger Agreement is terminated in accordance
                        with its terms.

                              (b) Notwithstanding the foregoing, this Agreement
                        shall in any event terminate with respect to any
                        Stockholder when such Stockholder no longer owns any
                        shares of Common Stock, or other warrants, options or
                        rights to subscribe for or purchase Common Stock.


<PAGE>   29



                                   ARTICLE XII

                                  MISCELLANEOUS

         Section 12.1. Successors and Assigns. Except as otherwise provided
herein, all the terms and provisions of this Agreement shall be binding upon,
shall inure to the benefit of and shall be enforceable by the respective
successors and assigns of the parties hereto. No Stockholder may assign any of
its rights or obligations hereunder to any Person other than in accordance with
this Agreement to a transferee that has complied in all respects with the
requirements of this Agreement. The Company may not assign any of its rights or
obligations hereunder to any other Person. If any transferee of any Stockholder
shall acquire any shares of Common Stock in any manner, whether by operation of
law or otherwise, such shares shall be held subject to all of the terms of this
Agreement, and by taking and holding such shares such Person shall be entitled
to receive the benefits of and be conclusively deemed to have agreed to be bound
by and to comply with all of the terms and provisions of this Agreement.

         Section 12.2. Amendment and Modification; Waiver of Compliances;
Conflicts.

                        (a) This Agreement may be amended only by a written
                  instrument duly executed by each of the Stockholders party
                  hereto. In the event of the amendment or modification of this
                  Agreement in accordance with its terms, the Stockholders shall
                  cause the Board of Directors to meet within 30 calendar days
                  following such amendment or modification or as soon thereafter
                  as is practicable for the purpose of adopting any amendment to
                  the Certificate of Incorporation and By-Laws that may be
                  required as a result of such amendment or modification to this
                  Agreement, and, if required, proposing such amendments to the
                  Stockholders entitled to vote thereon, and the Stockholders
                  agree to vote in favor of such amendments.

                        (b) Except as otherwise provided in this Agreement, any
                  failure of any of the parties to comply with any obligation,
                  covenant, agreement or condition herein may be waived by the
                  party entitled to the benefits thereof only by a written
                  instrument signed by the party granting such waiver, but such
                  waiver or failure to insist upon strict compliance with such
                  obligation, covenant, agreement or condition shall not operate
                  as a waiver of, or estoppel with respect to, any subsequent or
                  other failure.

                        (c) In the event of any conflict between the provisions
                  of this Agreement and the provisions of any other agreement,
                  the provisions of this Agreement shall govern and prevail.

         Section 12.3. Notices. All notices and other communications provided
for hereunder shall be in writing and delivered by hand or sent by first class
mail or sent by telecopy (with such telecopy to be confirmed promptly in writing
sent by first class mail), sent as follows:

                            (i)    If to the Buyer, addressed to

                                   Calpine Corporation
                                   50 West San Fernando Street
                                   San Jose, California  95113
<PAGE>   30

                           Attention:  John T. King
                           Telecopy:  (408) 995-0505

                           with a copy to:

                           Howard, Smith & Levin LLP
                           1330 Avenue of the Americas
                           New York, New York 10019
                           Attention:  William R. Collins, Esq.
                           Telecopy No.:  (212) 841-1010

                           (ii)     If to NRG, addressed to

                           NRG Energy, Inc.
                           1221 Nicollet Mall, Suite 700
                           Minneapolis, Minneapolis 55403-2445
                           Attention:  James J. Bender, Esq.
                           Telecopy No.:  (612) 373-5392

                           with a copy to

                           Skadden, Arps, Slate, Meagher & Flom LLP
                           1440 New York Avenue NW
                           Washington, D.C. 20005
                           Attention:  Jeanine L. Matte, Esq.
                           Telecopy No.: (202) 393-5760


<PAGE>   31



                           (iii)    If to the Company, addressed to

                           Cogeneration Corporation of America
                           c/o Calpine Corporation
                           50 West San Fernando Street
                           San Jose, California  95113
                           Attention:  John T. King
                           Telecopy No.:  (408) 995-0505

                           with a copy to

                           Howard, Smith & Levin LLP
                           1330 Avenue of the Americas
                           New York, New York 10019
                           Attention:  William R. Collins, Esq.
                           Telecopy No.:  (212) 841-1010

or to such other address or addresses or telecopy number or numbers as any of
the parties hereto may most recently have designated in writing to the other
parties hereto by such notice. All such communications shall be deemed to have
been given or made when so delivered by hand or sent by telecopy, or three
business days after being so mailed.

                  Section 12.4 Entire Agreement: Governing Law; Consent to
Jurisdiction

                        (a) This Agreement and the other writings referred to
                  herein or delivered pursuant hereto which form a part hereof
                  contain the entire agreement among the parties hereto with
                  respect to the subject transactions contemplated hereby and
                  supersede all prior oral and written agreements and memoranda
                  and undertakings among the parties hereto with regard to this
                  subject matter. The Company represents to the Stockholders
                  that the rights granted to the holders hereunder do not in any
                  way conflict with and are not inconsistent with the rights
                  granted or obligations accepted under any other agreement
                  (including the Certificate of Incorporation) to which the
                  Company is a party. Neither the Company nor any Subsidiary of
                  the Company will hereafter enter into any agreement with
                  respect to its equity or debt securities which is inconsistent
                  with the rights granted to any Stockholder under this
                  Agreement without obtaining the prior written consent of the
                  Stockholder whose rights would be thereby affected.

                        (b) This Agreement shall be governed by and construed in
                  accordance with the laws of the State of Delaware (without
                  giving effect to the choice of law principles thereof).

                        (c) Each of the parties hereto (a) consents to submit
                  itself to the personal jurisdiction of any federal court
                  located in the State of Delaware or any Delaware state court
                  in the event any dispute arises out of this Agreement or any
                  of the transactions contemplated by this Agreement, (b) agrees
                  that it will not

<PAGE>   32

                  attempt to deny or defeat such personal jurisdiction by motion
                  or other request for leave from any such court and (c) agrees
                  that it will not bring any action relating to this Agreement
                  or any of the transactions contemplated by this Agreement in
                  any court other than a federal or state court sitting in the
                  State of Delaware.

                  Section 12.5. Severability. The validity or unenforceability
of any provisions of this Agreement in any jurisdiction shall not affect the
validity, legality or enforceability of the remainder of this Agreement in such
jurisdiction or the validity, legality or enforceability of this Agreement,
including any such provision, in any other jurisdiction, it being intended that
all rights and obligations of the parties hereunder shall be enforceable to the
fullest extent permitted by law.

                  Section 12.6. Injunctive Relief. The Stockholders acknowledge
and agree that a violation of any of the terms of this Agreement will cause the
Stockholders irreparable injury for which an adequate remedy at law is not
available. Therefore, the Stockholders agree that each Stockholder shall be
entitled, in addition to any other remedy to which they may be entitled at law
or in equity, (i) to an injunction, restraining order or other equitable relief
from any court of competent jurisdiction, restraining any Stockholder from
committing any violations of the provisions of this Agreement, and (ii) to
compel specific performance of the terms of this Agreement.

                  Section 12.7. Availability of Agreement. For so long as this
Agreement shall be in effect, this Agreement shall be made available for
inspection by any Stockholder upon request at the principal executive offices of
the Company.

                  Section 12.8. Headings. The section and paragraph headings
contained in this Agreement are for reference purposes only and shall not affect
in any way the meaning or interpretation of this Agreement.

                  Section 12.9. Expenses. Except as otherwise expressly provided
in Section 5.1(b) or any other provision of this Agreement, each of the Buyer,
the Company and NRG will bear its own costs and expenses incurred in connection
with this Agreement and the transactions contemplated hereby and the Merger.
This Section 12.9 shall survive the termination of this Agreement.

                  Section 12.10. Adjustments to Prevent Dilution, Etc. In the
event of a stock dividend or distribution, or any change in the common stock of
Cogen by reason of any stock dividend, split-up, reclassification,
recapitalization, combination or the exchange of shares, the term "shares" used
herein shall be deemed to refer to and include the shares of common stock of
Cogen owned by NRG as well as such stock dividends and distributions and any
shares into which or for which any or all of the shares of common stock of Cogen
may be changed or exchanged. In such event, the amount to be paid per share by
the Buyer shall be proportionately reduced.

                  Section 12.11. Counterparts. This Agreement may be executed in
two or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.

                      [The next page is the signature page]


<PAGE>   33



                  IN WITNESS WHEREOF, the parties hereto have caused this
Agreement to be duly executed as of the date first above written.

                          CALPINE CORPORATION

                                 By: __________________________
                                 Name:   John T. King
                                 Title:  Vice President - Business Development

                          NRG ENERGY, INC.

                                 By: __________________________
                                 Name:   David H. Peterson
                                 Title:  Chairman, President and
                                         Chief Executive Officer

                          CALPINE EAST ACQUISITION CORP.

                                 By: _________________________
                                 Name:   John T. King
                                 Title:  Vice President



                                       33

<PAGE>   1

                                                                     Exhibit (4)

                            CONFIDENTIALITY AGREEMENT

         This Confidentiality Agreement (this "Agreement"), effective May 17,
1999, relates to the proposed exchange of confidential information between
Calpine Corporation, a corporation organized under the laws of the State of
Delaware ("Calpine"), and Cogeneration Corporation of America, a corporation
organized under the laws of the State of Delaware ("CogenAmerica") in connection
with the consideration by Calpine of a possible transaction with CogenAmerica or
any of CogenAmerica's principal shareholders (each a "Possible Transaction").

         CogenAmerica and Calpine agree as follows with respect to (i)
confidential information (whether in the form of documents, oral communications
or otherwise) disclosed by CogenAmerica to Calpine in connection with a Possible
Transaction (the "CogenAmerica Information"), and (ii) confidential information
(whether in the form of documents, oral communications or otherwise) disclosed
by Calpine to CogenAmerica in connection with a possible Transaction (the
"Calpine Information"):

      1.    (a) Subject to the exceptions set forth in Paragraph 3 Calpine
            agrees (i) to treat all CogenAmerica Information as the strictly
            confidential and proprietary information of CogenAmerica and to not
            use the CogenAmerica Information for any purpose other than the
            evaluation and performance of a Possible Transaction by Calpine or
            disclose CogenAmerica Information to third parties other than to
            Calpine's directors, officers, affiliates, agents advisors
            (including, without limitation, financial advisors, attorneys and
            accountants) and employees (collectively, "Calpine Representatives")
            without the prior written permission of CogenAmerica; and (ii) to
            not disclose to any person other than to Calpine Representatives
            that the CogenAmerica Information has been made available, that
            discussions or negotiations are taking place or have taken place
            concerning a Possible Transaction, or any of the terms or other
            facts with respect to a Possible Transaction, including the status
            thereof and the previous discussions and exchange of correspondence
            between Calpine and NRG Energy, Inc. ("NRG") relating to
            CogenAmerica and NRG's ownership interest in CogenAmerica, without
            the prior written permission of CogenAmerica.

            (b) Subject to the exceptions set forth in Paragraph 3, CogenAmerica
            agrees (i) to treat all Calpine Information as the strictly
            confidential and proprietary information of Calpine and to not use
            the Calpine Information for any purpose other than the evaluation
            and performance of a Possible Transaction by CogenAmerica or
            disclose Calpine Information to third parties other than to
            CogenAmerica's directors, officers, affiliates, agents advisors
            (including, without limitation, financial advisors, attorneys and
            accountants) and employees (collectively, "CogenAmerica
            Representatives") without the prior written permission of Calpine;
            and (ii) to not disclose to any person other than to CogenAmerica
            Representatives that the Calpine Information has been made
            available, that discussions or negotiations are taking place or have
            taken place concerning a Possible Transaction, or any of the terms
            or other facts with respect to a

<PAGE>   2
            Possible Transaction, including the status thereof and the previous
            discussions and exchange of correspondence between Calpine and NRG
            Energy, Inc. ("NRG") relating to CogenAmerica and NRG's ownership
            interest in CogenAmerica, without the prior written permission of
            Calpine.

      2.    Subject to the exceptions set forth in Paragraph 3, Calpine will not
            disclose any CogenAmerica Information, and CogenAmerica will not
            disclose any Calpine Information, to any Calpine Representatives or
            CogenAmerica Representatives, respectively, to whom disclosure is
            necessary in connection with the evaluation and performance of a
            Possible Transaction. All Calpine Representatives to whom
            CogenAmerica Information and other information relating to a
            Possible Transaction is made available by Calpine shall be under
            confidentiality obligations with Calpine for the benefit of
            CogenAmerica consistent with this Agreement. All CogenAmerica
            Representatives to whom Calpine Information and other information
            relating to a Possible Transaction is made available by CogenAmerica
            shall be under confidentiality obligations with CogenAmerica for the
            benefit of Calpine consistent with this Agreement.

      3.    (a) The provisions of Paragraphs 1 and 2 shall not apply to any
            CogenAmerica Information which (i) is or becomes publicly known
            through no fault of Calpine, (ii) is disclosed to Calpine on a
            non-confidential basis by a third party whom Calpine believes after
            due inquiry is entitled to disclose it, (iii) Calpine can
            demonstrate on the basis of written records was already known to it
            on a non-confidential basis prior to receipt from CogenAmerica, or
            (iv) subject to Paragraph 3(c), is required to be disclosed by law
            or legal process.

            (b) The provisions of Paragraphs 1 and 2 shall not apply to any
            Calpine Information which (i) is or becomes publicly known through
            no fault of CogenAmerica, (ii) is disclosed to CogenAmerica on a
            non-confidential basis by a third party whom CogenAmerica believes
            after due inquiry is entitled to disclose it, (iii) CogenAmerica can
            demonstrate on the basis of written records was already known to it
            on a nonconfidential basis prior to receipt from Calpine, or (iv)
            subject to Paragraph 3(c), is required to be disclosed by law or
            legal process.

            (c) In the event that Calpine or any of its representatives, or
            CogenAmerica or any of its representatives receive a request or are
            required (by deposition, interrogatory, request for documents,
            subpoena, civil investigative demand or similar process) to disclose
            all or any part of the information protected by this Agreement (the
            said party being herein designated as a "Compelled Disclosure
            Party"), the Compelled Disclosure Party or its representative as the
            case may be, agrees to (i) immediately notify the other party to
            this Agreement (the "Protected Party") of the existence, terms and
            circumstances surrounding such a request or requirement, (ii)
            consult with the Protected Party on the advisability of taking
            legally available steps to resist or narrow such request or
            requirement, and (iii) assist the Protected Party in seeking a
            protective order or other appropriate remedy. In the event that such
            protective order or other remedy is not obtained or that the
            Protected Party waives compliance with the provisions hereof, (1)
            the Compelled Disclosure Party or its representative, as the case

                                       2
<PAGE>   3

            may be, may disclose to any tribunal only that portion of the
            information protected hereunder which it is advised by counsel is
            legally required to be disclosed and shall exercise reasonable
            efforts to obtain assurance that confidential treatment will be
            accorded such and (2) said party shall not be liable for such
            disclosure unless disclosure to any such tribunal was caused by or
            resulted from a previous disclosure by said party, or any of its
            representatives, not permitted by this Agreement.

      4.    (a) Upon the written request at any time of CogenAmerica, Calpine
            agrees that all copies of CogenAmerica Information will be promptly
            returned to CogenAmerica and that all copies of any analyses,
            compilations, forecasts, studies or other documents based upon or
            containing CogenAmerica Information prepared by Calpine, or its
            directors, officers, affiliates, agents or employees, will be
            promptly destroyed and such destruction will be promptly confirmed
            in writing to CogenAmerica.

            (b) Upon the written request at any time of Calpine, CogenAmerica
            agrees that all copies of Calpine Information will be promptly
            returned to Calpine and that all copies of any analyses,
            compilations, forecasts. studies or other documents based upon or
            containing Calpine Information prepared by CogenAmerica, or its
            directors, officers, affiliates, agents or employees, will be
            promptly destroyed and such destruction will be promptly confirmed
            in writing to Calpine.

      5.    Calpine and CogenAmerica agree that Calpine Information and
            CogenAmerica Information include confidential and proprietary
            information and trade secrets. Calpine and CogenAmerica acknowledge
            that remedies at law may be inadequate to protect against breach of
            this Agreement, and each party hereby agrees that the other party
            may seek injunctive relief to prevent disclosure of Calpine
            Information and CogenAmerica Information.

      6.    It is understood that this Agreement does not obligate either
            Calpine or CogenAmerica to enter into any further agreement or to
            consummate in any way a Possible Transaction. Until the execution by
            both parties of a binding written agreement setting forth the terms
            and conditions of a Possible Transaction, each party agrees that
            either party may withdraw from the negotiations concerning a
            Possible Transaction at any time for any reason without any
            liability to the other party of any kind whatsoever with respect to
            a Possible Transaction.

      7.    Calpine agrees that, until the earlier of eighteen (18) months from
            the date hereof or the closing of a Possible Transaction, unless
            such shall have been specifically agreed to in advance by
            CogenAmerica, Calpine will not, in any manner, directly or
            indirectly, (a) effect or seek, offer or propose (whether publicly
            or otherwise) to effect, or cause or participate in or in any way
            assist any other person to effect or seek, offer or propose (whether
            publicly or otherwise) to effect or participate in, (i) any
            acquisition of any securities (or beneficial ownership thereof) or
            any material portion of the assets of CogenAmerica or any of its
            subsidiaries, (ii) any tender or exchange offer or merger or other
            business combination involving CogenAmerica or any of its
            subsidiaries, (iii) any recapitalization, restructuring,
            liquidation, dissolution or other extraordinary transaction with
            respect to CogenAmerica or any of its

                                       3
<PAGE>   4

            subsidiaries, or (iv) any "Solicitation" of "proxies" (as such terms
            are used in the proxy rules of the Securities and Exchange
            Commission) or consents to vote any voting securities of
            CogenAmerica, (b) form, join or in any way participate in a "group"
            (as defined under the Securities Exchange Act of 1934, as amended)
            for any of the purposes referred to in Section 7(a), (c) otherwise
            act, alone or in concert with others, to seek to control or
            influence the management, Board of Directors or policies of
            CogenAmerica, (d) take any action which might force CogenAmerica to
            make a public announcement regarding any of the types of matters set
            forth in (a) above, or (e) enter into any discussions or
            arrangements with any third party (other than Calpine
            Representatives) with respect to any of the foregoing; provided,
            however, that Calpine shall be entitled to make nonpublic proposals
            relating to NRG Energy's shareholdings in CogenAmerica and to
            discuss the terms thereof with CogenAmerica and CogenAmerica
            Representatives and with NRG Energy, Inc. and its directors,
            officers, affiliates, agents advisors (including, without
            limitation, financial advisors, attorneys and accountants) and
            employees. Calpine also agrees during any such period not to request
            that CogenAmerica (or its directors, officers, employees or agents),
            directly or indirectly, amend or waive any provision of this
            paragraph.

      8.    This Agreement shall be in force and effect for a period of two (2)
            years from the date hereof and shall be governed by the laws of the
            State of New York, excluding its conflicts of laws rules. This
            Agreement may be executed in counterparts which together will
            constitute the same instrument. This Agreement may be executed by
            manual signature transmitted electronically and any such signature
            will be deemed to be a manual execution.

      9.    EACH OF CALPINE AND COGENAMERICA HEREBY IRREVOCABLY WAIVES ANY
            RIGHTS THAT THEY MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY
            LITIGATION BASED UPON, OR ARISING OUT OF, THIS AGREEMENT OR ANY
            COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS OR ACTIONS OF ANY
            OF THEM RELATING HERETO.

ACCEPTED AND AGREED AS OF THE DATE FIRST WRITTEN ABOVE:

Cogeneration Corporation of America                 Calpine Corporation

By: /s/ Julie A. Jorgensen                          By: /s/ Robert D. Kelly
    ----------------------                              -------------------
Title: President and Chief Executive Officer        Title: Senior Vice President
Date:  May 17, 1999                                 Date: May 17, 1999


                                       4


© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission