<PAGE>
Exhibit I-1
List and Description of Subsidiaries and Investments Of Unicom
Corporation (Other than "Public-Utility"
Companies) As of June, 2000
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Name Jurisdiction Description Authority
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Subsidiaries of Unicom
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<S> <C> <C> <C>
Unicom Enterprises Inc Illinois First tier holding company for Unicom See below
non-regulated investments
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Unicom Mechanical Services Inc Delaware design, build, test, repair, distribute Rule 58(b)(1)(ii) and (vii);
products and finance heating, cooling, CINergy HCAR 35-26662
ventilation and industrial process systems,
and high and low voltage electrical power
systems for commercial and industrial
customers
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V. A. Smith Company Illinois Subsidiary of Unicom Mechanical Services See Unicom Mechanical Services
Inc. Inc
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UMS Acquisition Corp Delaware Subsidiary of Unicom Mechanical Services Inc See Unicom Mechanical Services
Inc
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Inc
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MMCD, Inc Illinois Subsidiary of UMS Acquisition Corp See Unicom Mechanical Services
Inc
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Access Systems Inc. Illinois Environmental control; building automation See Unicom Mechanical Services
and security systems for commercial and Inc
industrial customers
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Hoekstra Building Automation, Illinois Environmental control; building automation See Unicom Mechanical Services
Inc and security systems for commercial and Inc
industrial customers
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MMSD, Inc Illinois Subsidiary of UMS Acquisition Corp See Unicom Mechanical Services
Inc
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Unicom Power Holdings Inc Delaware owns electric power production facilities; Rule 58(b)(1)(vii) and (viii)
full service developer engaged in the
design, construction, financing, ownership
and operation of energy production
facilities
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Name Jurisdiction Description Authority
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<S> <C> <C> <C>
Unicom Investment Inc. Illinois formed to receive the proceeds from the Passive tax advantaged
fossil sale pending eventual use of those investment in arrangement not
funds. Unicom has entered into a like-kind involving a public utility
exchange transaction to minimize taxes due company. Central and South West
on the sale of its fossil fuel generating Corp., HCAR 35-23578.
stations. The transaction involves
acquisition of leasehold interest in
generating facilities owned by two
governmental entities with lease back to
those entities. No Exelon affiliate will
participate in any way in the operation of
the generating factilities.
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Scherer Holdings 1, LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Scherer Holdings 2, LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Scherer Holdings 3, LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Wansley Holdings 1, LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Wansley Holdings 2, LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Spruce Holdings G.P. LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Spruce Holdings L.P. 2000 LLC Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Unicom
Investment Inc.
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Spruce Equity Holdings L.P. Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Spruce
Holdings G.P. LLC
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Name Jurisdiction Description Authority
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<S> <C> <C> <C>
Spruce Holdings Trust Special purpose entity relating to like See Unicom Investment Inc.
kind exchange transaction; owned by Spruce
Holdings G.P. LLC
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Unicom Energy Inc Delaware markets electricity and natural gas where Rule 58(b)(1)(v)
retail competition is established
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Unicom Energy Ohio, Inc. Delaware markets natural gas where retail Rule 58(b)(1)(v)
competition is established
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Unicom Energy Services Inc. Illinois distributed generation including Rule 58(b)(1)(i), (vii) and
microturbine and similar (viii)
technology; turnkey
energy and operational
solutions; demand-side and
supply side solutions;
energy performance
contracting and guaranties;
custom lighting solutions;
financing related thereto
Unicom Distributed Energy
division sells, finances,
installs and maintains
on-site generation and
cogeneration Unicom Active
Energy Management division
provides a suite of energy
information products and
related consultative
services (forecast daily
energy usage and track
historical energy
consumption) eQuater
provides energy information
services
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Unicom Gas Services LLC Delaware Markets natural gas where retail Rule 58(b)(1)(v)
competition is established (To be merged
with Unicom Energy Inc).
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Unicom Power Marketing Inc. Delaware wholesale electricity and natural gas Rule 58(b)(1)(v)
marketing
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Unicom HealthCare Management Illinois management of SFAS 106 contingent medical
Inc. plan liabilities
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UT Holdings Inc. Delaware district energy company; operates district Rule 58(b)(1)(vi) and (vii)
cooling systems; district energy systems
(chilled water, steam and/or hot water);
construction and operating services for
central energy plan
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Name Jurisdiction Decsription Authority
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<S> <C> <C> <C>
Unicom Thermal Delaware Subsidiary of UT Holdings Inc. See UT Holdings Inc.
Development Inc
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Unicom Thermal Illinois Subsidiary of UT Holdings Inc. See UT Holdings Inc.
Technologies Inc
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Unicom Thermal Delaware Subsidiary of UT Holdings Inc. See UT Holdings Inc.
Technologies Boston
Inc.
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Northwind Boston LLC Massachusetts 25% held by Unicom Thermal See UT Holdings Inc
Technologies Boston Inc.
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Unicom Thermal Technologies Delaware Subsidiary of UT Holdings Inc See UT Holdings Inc
Houston Inc.
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Northwind Houston LLC Delaware 25% held by Unicom Thermal Technologies See UT Holdings Inc
Houston Inc
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Northwind Houston LP Delaware 25% held by Northwind Houston LLC See UT Holdings Inc
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Unicom Thermal Technologies Delaware Subsidiary of UT Holdings Inc (operates in See UT Holdings Inc
North America Inc. Canada)
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Northwind Thermal Technologies New Brunswick Subsidiary of Unicom Thermal Technologies See UT Holdings Inc
Canada Inc. North America Inc.
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Unicom Thermal Technologies New Brunswick Subsidiary of Northwind Thermal See UT Holdings Inc
Inc. Technologies Canada Inc.
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UTT National Power Inc. Illinois Subsidiary of UT Holdings Inc See UT Holdings Inc
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Northwind Midway LLC Delaware Subsidiary of UTT National Power Inc. See UT Holdings Inc
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UTT Nevada Inc. Nevada Subsidiary of UT Holdings Inc See UT Holdings Inc
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Northwind Aladdin LLC (75%) Nevada Subsidiary of UTT Nevada Inc. See UT Holdings Inc
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Northwind Las Vegas LLC (50%) Nevada Subsidiary of UTT Nevada Inc. See UT Holdings Inc
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Northwind Chicago LLC (100%) Delaware Subsidiary of UT Holdings Inc. See UT Holdings Inc
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UTT Phoenix, Inc. Delaware Subsidiary of UT Holdings Inc See UT Holdings Inc
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Northwind Arizona Development Delaware Subsidiary of UTT Phoenix Inc. See UT Holdings Inc
LLC (50%)
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</TABLE>
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Name Jurisdiction Decsription Authority
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<S> <C> <C> <C>
Northwind Phoenix LLC (50%) Delaware Subsidiary of UTT Phoenix Inc. See UT Holdings Inc
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Unicom Resources Inc. Illinois [inactive]
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Unicom Assurance Bermuda A direct sub of Unicom. Columbia Insurance
------------------
Company Limited Insurance captive Corporation, Ltd. HCAR
----------------
No. 27051
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Subsidiaries of Commonwealth Edison
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ComEd Financing I Delaware Special purpose financing vehicle New Century Energies,
HCAR No. 26748; New
Century Energies, HCAR
26750; Conectiv, HCAR
26833; Cinergy Corp.,
HCAR 26984; Dominion
Resources, HCAR 27112
and SCANA Corporation,
HCAR 27135
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ComEd Financing II Delaware Special purpose financing vehicle New Century Energies,
HCAR No. 26748; New
Century Energies, HCAR
26750; Conectiv, HCAR
26833; Cinergy Corp.,
HCAR 26984; Dominion
Resources, HCAR 27112
and SCANA Corporation,
HCAR 27135
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ComEd Funding, LLC Delaware Special purpose financing vehicle New Century Energies,
HCAR No. 26748; New
Century Energies, HCAR
26750; Conectiv, HCAR
26833; Cinergy Corp.,
HCAR 26984; Dominion
Resources, HCAR 27112
and SCANA Corporation,
HCAR 27135
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5
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Name Jurisdiction Description Authority
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<S> <C> <C> <C>
ComEd Transitional Delaware Special purpose financing vehicle New Century Energies,
Funding Trust HCAR No. 26748; New
Century Energies, HCAR
26750; Conectiv, HCAR
26833; Cinergy Corp.,
HCAR 26984; Dominion
Resources, HCAR 27112
and SCANA Corporation,
HCAR 27135
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Commonwealth Research Illinois Engaged in research, development and
Corporation testing activities to ensure a safe,
economical and adequate electric power
supply for ComEd; holds certain energy
related patents
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Concomber Ltd Bermuda Captive insurance company Columbia Insurance
-------------------
Corporation, Ltd. HCAR
----------------
No. 27051
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Edison Development Delaware Holds real estate; real estate joint Ameren, HCAR 35-26809
Company ventures; for economic development
and community development purposes;
adjacent to ComEd facility.
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Lincoln Commerce Center 50% owned by Edison Development Company; Ameren, HCAR 35-26809
owns improved and unimproved real estate;
for economic development and community
development purposes; adjacent to ComEd
facility.
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Commerce Distribution Center 50% owned by Edison Development Company; Ameren, HCAR 35-26809
owns improved and unimproved real estate;
for economic development and community
development purposes; adjacent to ComEd
facility.
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Concepts II Building 50% owned by Edison Development Company; Ameren, HCAR 35-26809
owns improved and unimproved real estate;
for economic development and community
development purposes; adjacent to ComEd
facility.
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Concepts III Building 50% owned by Edison Development Company; Ameren, HCAR 35-26809
owns improved and unimproved real estate;
for economic development and community
development purposes; adjacent to ComEd
facility.
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Edison Development Canada Exploration, development, mining and Rule 58(b)(1)(ix)
Canada Inc. milling of uranium ore
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Edison Finance Partnership Ontario Intercompany financing with Edison New Century Energies,
Development Canada and Northwind Thermal HCAR No. 26748
Technologies Canada
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</TABLE>
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Non-subsidiary investments of Unicom
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Name Percentage Description Authority
ownership
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<S> <C> <C> <C>
Apeco Corporation (Common less than 5% passive and/or deminimis;
Stock - $.50 Par Value) Ameren, HCAR 35-
26809; WPL Holdings,
HCAR 35-26856
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Chicago Community Ventures, less than 5% enterprise small business investment company passive and/or deminimis;
Inc. Ameren, HCAR 35-26809; WPL
Holdings, HCAR 35-26856
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Chicago Equity Fund less than 5% funds rehab of low and moderate income passive and/or deminimis;
housing Ameren, HCAR 35-26809; WPL
Holdings, HCAR 35-26856;
economic development, Ameren
HCAR 35-26809
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Dearborn Park Corporation less than 5% passive and/or deminimis;
Ameren, HCAR 35-26809; WPL
Holdings, HCAR 35-26856
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I.L.P. Fund C/O Chicago less than 5% venture capital small business fund passive and/or deminimis;
Capital Fund Ameren, HCAR 35-26809; WPL
Holdings, HCAR 35-26856
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Illinois Venture Fund less than 5% venture capital new technology in Illinois passive and/or deminimis;
(Unibanc Trust) Ameren, HCAR 35-26809; WPL
Holdings, HCAR 35-26856
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</TABLE>
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Non-subsidiary investments of Unicom
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Name Percentage Description Authority
ownership
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<S> <C> <C> <C>
Boston Financial Institutional Passive investments of tax advantaged Ameren Corp., HCAR No.
Tax Credit Fund X, Related affordable housing credit funds; --------------
Corporate Partners IV, L.P.; total investment at March 31, 2000 35-26809
Boston Financial Institutional approximately $120 million
Tax Credit Fund XIX; Related
Corporate Partners XII, L.P.,
Boston Capital Corp. XIV,
Boston Financial Institutional
Tax Credit Fund XXI, Related
Corporate Partners XIV, L.P.,
Summit Corporate Tax Credit
Fund II, USA Institutional Tax
Credit Fund XXII
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Pantellos Corporation less than 5% Business to Business e-commerce business Section 34; filed for
which will develop supply chain resources certification as ETC
for utilities and others over the internet
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Automated Power Exchange less than 5% Competitive power exchange business; Rule 58 (b)(1)(v)
competes with California PX and in other
states
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UTECH Climate Challenge Fund, venture capital investments in businesses Rule 58(b)(1)(ii); passive
L.P. engaged in developing or commercializing and/or deminimis;
electrotechnologies and renewable energy Ameren, HCAR 35-
technologies 26809; WPL Holdings, HCAR
35-26856
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Utility Competitive Advantage venture capital investments in businesses GPU, Inc. HCAR 27139;
Fund II, LLC engaged in communications, the Internet, passive and/or deminimis;
customer service opportunities and Ameren, HCAR 35-26809;
companies with products or services to WPL Holdings, HCAR 35-26856
help utilities retain and build customer
base, improve core operating efficiencies
and generate new revenue sources
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</TABLE>
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