<PAGE>
LIMITED POWER OF ATTORNEY
TNPC, INC.
The undersigned director of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and on my behalf in my
capacity as a director of TNPC in connection with, and only in connection with,
the filing of this registration statement (including, but not limited to, the
execution of any and all instruments for me and in my name which such person may
deem necessary or advisable to enable TNPC to comply with the Securities Act of
1933, as amended (the "Act") and any rules, regulations and requirements of the
Securities and Exchange Commission, in connection with the filing of this
registration statement), including specifically, but not limited to, the power
and authority to sign for me any and all amendments, including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act; and I do hereby ratify and confirm
all that such person or persons shall do or cause to be done by virtue hereof.
By: /s/ LOU L. PAI
------------------------------
Name: Lou L. Pai
Title: Director
Date: July 13, 2000
<PAGE>
POWER OF ATTORNEY
TNPC, INC.
The undersigned director and officer of TNPC, Inc. ("TNPC") does hereby
constitute and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly,
and each of them, with full power of substitution, my true and lawful
attorneys-in-fact and agents to do any and all acts and things in my name and
behalf in my capacities as director and officer, and to execute any and all
instruments for me and in my name in the capacities indicated below which such
person may deem necessary or advisable to enable TNPC to comply with the
Securities Act of 1933, as amended (the "Act") and any rules, regulations and
requirements of the Securities and Exchange Commission, in connection with this
registration statement, including specifically, but not limited to, power and
authority to sign for me any and all amendments (including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act) hereto; and I do hereby ratify and
confirm all that such person or persons shall do or cause to be done by virtue
hereof.
By: /s/ H. EUGENE LOCKHART
------------------------------
Name: H. Eugene Lockhart
Title: President, Chief Executive
Officer and Director
Date: July 13, 2000
------------------------------
<PAGE>
POWER OF ATTORNEY
TNPC, INC.
The undersigned director and officer of TNPC, Inc. ("TNPC") does hereby
constitute and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly,
and each of them, with full power of substitution, my true and lawful
attorneys-in-fact and agents to do any and all acts and things in my name and
behalf in my capacity as director and officer, and to execute any and all
instruments for me and in my name in the capacities indicated below which such
person may deem necessary or advisable to enable TNPC to comply with the
Securities Act of 1933, as amended (the "Act") and any rules, regulations and
requirements of the Securities and Exchange Commission, in connection with this
registration statement, including specifically, but not limited to, power and
authority to sign for me any and all amendments (including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act) hereto; and I do hereby ratify and
confirm all that such person or persons shall do or cause to be done by virtue
hereof.
By: /s/ WILLIAM I JACOBS
----------------------------------
Name: William I Jacobs
Title: Managing Director, Chief Financial
Officer and Director
Date: July 13, 2000
----------------------------------
<PAGE>
POWER OF ATTORNEY
TNPC, INC.
The undersigned officer of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and behalf in my capacity as
an officer of TNPC, and to execute any and all instruments for me and in my name
in the capacity indicated below which such person may deem necessary or
advisable to enable TNPC to comply with the Securities Act of 1933, as amended
(the "Act") and any rules, regulations and requirements of the Securities and
Exchange Commission, in connection with this registration statement, including
specifically, but not limited to, power and authority to sign for me in the
capacity indicated below and any and all amendments (including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act) hereto; and I do hereby ratify and
confirm all that such person or persons shall do or cause to be done by virtue
hereof.
By: /s/ STEPHEN NOLAN
----------------------------------
Name: Stephen Nolan
Title: Controller (Principal Accounting
Officer)
Date: July 13, 2000
----------------------------------
<PAGE>
LIMITED POWER OF ATTORNEY
TNPC, INC.
The undersigned officer of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and behalf in my capacity as
an officer of TNPC, and to execute any and all instruments for me and in my name
in the capacity indicated below which such person may deem necessary or
advisable to enable TNPC to comply with the Securities Act of 1933, as amended
(the "Act") and any rules, regulations and requirements of the Securities and
Exchange Commission, in connection with this registration statement, including
specifically, but not limited to, power and authority to sign for me in the
capacity indicated below and any and all amendments (including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act) hereto; and I do hereby ratify and
confirm all that such person or persons shall do or cause to be done by virtue
hereof.
By: /s/ KENNETH L. LAY
---------------------------------
Name: Kenneth L. Lay
Title: Director
Date: July 13, 2000
<PAGE>
LIMITED POWER OF ATTORNEY
TNPC, INC.
The undersigned director of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and on my behalf in my
capacity as a director of TNPC in connection with, and only in connection with,
the filing of this registration statement (including, but not limited to, the
execution of any and all instruments for me and in my name which such person may
deem necessary or advisable to enable TNPC to comply with the Securities Act of
1933, as amended (the "Act") and any rules, regulations and requirements of the
Securities and Exchange Commission, in connection with the filing of this
registration statement), including specifically, but not limited to, the power
and authority to sign for me any and all amendments, including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act; and I do hereby ratify and confirm
all that such person or persons shall do or cause to be done by virtue hereof.
By: /s/ JAMES V. DERRICK, JR.
------------------------------
Name: James V. Derrick, Jr.
Title: Director
Date: July 13, 2000
<PAGE>
LIMITED POWER OF ATTORNEY
TNPC, INC.
The undersigned director of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and on my behalf in my
capacity as a director of TNPC in connection with, and only in connection with,
the filing of this registration statement (including, but not limited to, the
execution of any and all instruments for me and in my name which such person may
deem necessary or advisable to enable TNPC to comply with the Securities Act of
1933, as amended (the "Act") and any rules, regulations and requirements of the
Securities and Exchange Commission, in connection with the filing of this
registration statement), including specifically, but not limited to, the power
and authority to sign for me any and all amendments, including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act; and I do hereby ratify and confirm
all that such person or persons shall do or cause to be done by virtue hereof.
By: /s/ ANDREW S. FASTOW
----------------------------------
Name: Andrew S. Fastow.
Title: Director
Date: July 13, 2000
<PAGE>
POWER OF ATTORNEY
TNPC, INC.
The undersigned director of TNPC, Inc. ("TNPC") does hereby constitute
and appoint H. Eugene Lockhart, William I Jacobs and Marc E. Manly, and each of
them, with full power of substitution, my true and lawful attorneys-in-fact and
agents to do any and all acts and things in my name and behalf in my capacity as
director, and to execute any and all instruments for me and in my name in the
capacity indicated below which such person may deem necessary or advisable to
enable TNPC to comply with the Securities Act of 1933, as amended (the "Act")
and any rules, regulations and requirements of the Securities and Exchange
Commission, in connection with this registration statement, including
specifically, but not limited to, power and authority to sign for me in the
capacity indicated below and any and all amendments (including pre-effective and
post-effective amendments or any other registration statement filed pursuant to
the provision of Rule 462(b) under the Act) hereto; and I do hereby ratify and
confirm all that such person or persons shall do or cause to be done by virtue
hereof.
By: /s/ PETER T. GRAUER
-------------------------------------
Name: Peter T. Grauer
Title: Director
Date: July 14, 2000
-----------------------------------
