Document:

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                                                                  EXHIBIT 10.5.3

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 1
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 1

                              AMENDED AND RESTATED
                         TRANSMISSION SERVICES AGREEMENT

            This AMENDED AND RESTATED TRANSMISSION SERVICES AGREEMENT
(hereinafter referred to as "AGREEMENT") is made as of June 29, 2001, between
NIAGARA MOHAWK POWER CORPORATION (hereinafter referred to as "NIAGARA MOHAWK")
and SITHE/INDEPENDENCE POWER PARTNERS, L.P. (hereinafter referred to as the
"PRODUCER").

      WHEREAS, NIAGARA MOHAWK and PRODUCER have previously entered into the
TRANSMISSION SERVICES AGREEMENT dated November 5, 1991, as amended on March 9,
1992 and May 11, 1994, which provides that NIAGARA MOHAWK will provide
transmission services to deliver electric energy and capacity from the
PRODUCTION FACILITY (as defined in Section 1.1) to Consolidated Edison Company
of New York, Inc. at the Pleasant Valley Substation; and

      WHEREAS NIAGARA MOHAWK and PRODUCER desire to amend the TRANSMISSION
SERVICES AGREEMENT further in certain respects and to restate the AGREEMENT
as set forth herein, in compliance with the Federal Energy Regulatory
Commission's (hereinafter referred to as "FERC") Order No. 614, 90 FERC
[Paragraph] 61,352 (2000); and

      WHEREAS, PRODUCER owns the PRODUCTION FACILITY (as defined in Section 1.1
below), which is interconnected with NIAGARA MOHAWK's bulk power transmission
system at the POINT OF RECEIPT (as defined in Section 5.1.1 below); and

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 2
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 2

      WHEREAS, PRODUCER may deliver electric energy, capacity, ancillary or
other services or any combination thereof under this AGREEMENT for sale to
Consolidated Edison Company of New York, Inc. (hereinafter referred to as the
"PURCHASER") or to another entity (hereinafter referred to as "ADDITIONAL
BUYER"); and

      WHEREAS, NIAGARA MOHAWK is directly interconnected with the PURCHASER at
the Pleasant Valley Substation (hereinafter referred to as the "POINT OF
DELIVERY"); and

      WHEREAS, the New York Independent System Operator (hereinafter referred to
as the "NYISO") provides transmission services pursuant to its Open Access
Transmission Tariff (as amended, supplemented or modified and in effect from
time to time, the "NYISO OATT"), and provides certain market and control area
services pursuant to its Market Administration and Control Area Services Tariff
(as amended, supplemented or modified and in effect from time to time, the
"NYISO SERVICES TARIFF"); and

      WHEREAS, the New York State electricity market has been restructured: (a)
to give the NYISO operational control over certain transmission facilities owned
by the Members of the Transmission Owners Committee of the Energy Association of
New York State (hereinafter referred to as the "MEMBER SYSTEMS"); and (b) to
establish the ISO ADMINISTERED MARKETS; as defined in the NYISO OATT; and

      WHEREAS, PRODUCER may, in PRODUCER's sole discretion, subject to the
provisions of the NYISO OATT, the NYISO SERVICES TARIFF and this AGREEMENT, as
applicable, sell electric energy, capacity, ancillary or other services, or any
combination thereof,

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 3
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 3

into the ISO ADMINISTERED MARKETS and/or may enter into any number of BILATERAL
TRANSACTIONS (as that term is defined in the NYISO SERVICES TARIFF) with
PURCHASER, any ADDITIONAL BUYER, or any other entity; and

      WHEREAS, PRODUCER desires to receive, and NIAGARA desires to furnish, the
transmission services provided in this AGREEMENT.

            NOW THEREFORE, in consideration of the mutual obligations and
undertakings set forth herein, the parties to this AGREEMENT covenant and agree
as follows;

1.    DESCRIPTION OF POWER PURCHASE AGREEMENT AND FACILITY FOR WHICH SERVICES
      WILL BE RENDERED

      1.1    PRODUCER owns, operates, and maintains a generation facility
located in Oswego County, New York (hereinafter referred to as the "PRODUCTION
FACILITY"). The PRODUCTION FACILITY is capable of generating approximately
9,000,000 MWH of electric energy annually and has a nominal rated capacity of
approximately 1060 MW (individually and together referred to as "ELECTRICITY").

      1.2    PRODUCER may, in its sole discretion, subject to the provisions of
the NYISO OATT, the NYISO SERVICES TARIFF, and this AGREEMENT, as applicable,
sell electric energy, capacity, ancillary or other services or any combination
thereof to PURCHASER, any ADDITIONAL BUYER, any other entity or into the ISO
ADMINISTERED MARKETS.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 4
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 4

      1.3     For purposes of this AGREEMENT, the commercial operation date (the
"COMMERCIAL OPERATION DATE") will have the same definition as the term "Date of
Commercial Operation" in the Energy Purchase Agreement between Producer and
Purchaser entered into on May 20, 1991 (hereinafter referred to as "Power
Purchase Agreement").

2.    REPRESENTATIONS AND WARRANTIES OF PRODUCER

      2.1     The Representations and Warranties of PRODUCER in Sections 2.2
and 2.3 are made as of November 1, 1991.

      2.2     PRODUCER is a limited partnership duly organized and validly
existing under the laws of the State of Delaware. PRODUCER is qualified to do
business under the laws of the state of New York, is in good standing under the
laws of the State of New York, has the power and authority to own its
properties, to carry on its business as now being conducted, and to enter into
this AGREEMENT and the transactions contemplated herein and perform and carry
out all covenants and obligations on its part to be performed under and pursuant
to this AGREEMENT, and is duly authorized to execute and deliver this AGREEMENT
and consummate the transactions contemplated herein.

      2.3     PRODUCER is not prohibited from entering into this AGREEMENT and
discharging and performing all covenants and obligations on its part to be
performed under and pursuant to this AGREEMENT. The execution and delivery of
this AGREEMENT, the consummation of the transactions contemplated herein and the
fulfillment of and compliance with the provisions of this AGREEMENT will not
conflict with or constitute a breach of or a

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 5
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 5

default under any of the terms, conditions or provisions of any law, rule or
regulation, any order, judgment, writ, injunction, decree, determination, award
or other instrument or legal requirement of any court or other agency of
government, the partnership agreement of PRODUCER or any contractual limitation,
corporate restriction or outstanding trust indenture, deed of trust, mortgage,
loan agreement, lease, other evidence of indebtedness or any other agreement or
instrument to which PRODUCER is a party or by which it or any of its property is
bound and will not result in a breach of or a default under any of the
foregoing. This AGREEMENT is the legal, valid and binding obligation of PRODUCER
enforceable in accordance with its terms.

3.    REPRESENTATIONS AND WARRANTIES OF NIAGARA MOHAWK

      3.1    The Representations and Warranties of NIAGARA MOHAWK in Sections
3.2 and 3.3 are made as of November 5, 1991.

      3.2    NIAGARA MOHAWK is a corporation duly organized, validly existing
and qualified to do business under the laws of the State of New York, is in good
standing under its certificate of incorporation and the laws of the State of New
York, has the corporate authority to own its properties, to carry on its
business as now being conducted, and to enter into this AGREEMENT and the
transactions contemplated herein and perform and carry out all covenants and
obligations on its part to be performed under and pursuant to this AGREEMENT,
and is duly authorized to execute and deliver this AGREEMENT and consummate the
transactions contemplated herein.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 6
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 6

      3.3    NIAGARA MOHAWK is not prohibited from entering into this AGREEMENT
and discharging and performing all covenants and obligations on its part to be
performed under and pursuant to this AGREEMENT. The execution and delivery of
this AGREEMENT, the consummation of the transactions contemplated herein and the
fulfillment of and compliance with the provisions of this AGREEMENT will not
conflict with or constitute a breach of or a default under any of the terms,
conditions or provisions of any law, rule or regulation, any order, judgment,
writ, injunction, decree, determination, award or other instrument or legal
requirement of any court or other agency of government, the certificate of
incorporation or bylaws of NIAGARA MOHAWK or any contractual limitation,
corporate restriction or outstanding trust indenture, deed of trust, mortgage,
loan agreement, lease, other evidence of indebtedness or any other agreement or
instrument to which NIAGARA MOHAWK is a party or by which it or any of its
property is bound and will not result in a breach of or a default under any of
the foregoing. This AGREEMENT is the legal, valid and binding obligation of
NIAGARA MOHAWK enforceable in accordance with its terms.

4.    INTERCONNECTION

      4.1    The parties understand and recognize that interconnection of the
PRODUCTION FACILITY with NIAGARA MOHAWK is required for NIAGARA MOHAWK to
provide the transmission services hereunder. NIAGARA MOHAWK's obligation to
provide transmission services hereunder is expressly contingent on the parties
entering into a separate agreement providing for the interconnection of the
PRODUCTION FACILITY with NIAGARA MOHAWK, (as amended, supplemented or modified,
and in effect from time to time,

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 7
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 7

"Interconnection Agreement"), and the completion of such interconnection in
accordance with the terms of the Interconnection Agreement.

5.    ELECTRIC TRANSMISSION SERVICE TO BE RENDERED

      5.1    Reserved for future use.

             5.1.1 As of the COMMERCIAL OPERATION DATE, provided that PRODUCER
has fulfilled all of its applicable obligations hereunder and contingent upon
the completion of the interconnection in accordance with the terms of the
Interconnection Agreement, NIAGARA MOHAWK shall, in accordance with GOOD UTILITY
PRACTICE, provide sufficient firm transmission capacity to transmit the amounts
of ELECTRICITY, up to and including the CONTRACT DEMAND specified in Schedule A,
from the POINT OF RECEIPT (as defined below) to the POINT OF DELIVERY at the
rate specified in Schedule B, subject to the remaining provisions of this
AGREEMENT. As used herein, the words "POINT OF RECEIPT" shall mean the points of
interconnection between the PRODUCTION FACILITY and NIAGARA MOHAWK's bulk power
transmission system located within the Independence switchyard owned by NIAGARA
MOHAWK adjacent to the PRODUCTION FACILITY at the motor operated switches
commonly referred to as Switch Number 273 and Switch Number 283. ELECTRICITY
shall be delivered to PURCHASER at approximately 345,000 volts, 60 Hertz, and
three (3) phase. "GOOD UTILITY PRACTICE" as used in this AGREEMENT shall have
the same meaning as "Good Utility Practice" as defined in the NYISO OATT and
shall include all those practices, methods, and acts, that at a particular time
in the exercise of reasonable

\
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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 8
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 8

judgment, would have been expected to accomplish the desired result in a manner
consistent with regulations, reliability, safety, environmental protection,
economy and expedition.

            The Contract Demand shall initially be 805 MW; provided that
pursuant to a capability test conducted as soon as is practicable after the
COMMERCIAL OPERATION DATE, PRODUCER may revise the Contract Demand to reflect
the maximum net capability of the PRODUCTION FACILITY; provided further that
such revision does not increase the Contract Demand above 853 MW. Thereafter,
PRODUCER may annually restate the Contract Demand to satisfy its requirements
for firm transmission capacity; provided that no such revision increases the
Contract Demand by more than two (2) percent above the previous year's Contract
Demand ; provided, further, that in no event shall NIAGARA MOHAWK be obligated
to provide firm transmission capacity in excess of 853 MW; and provided further
that during the period commencing on July 2, 1999 and ending on December 31,
2005, PRODUCER agrees that it will not exercise its rights to reduce the
Contract Demand below 853 MW. PRODUCER's agreement not to exercise its rights to
reduce the Contract Demand below 853 MW during the period from July 2, 1999 to
December 31, 2005 is based upon and made in reliance upon NIAGARA MOHAWK's
representation that, as of June 29, 2001, NIAGARA MOHAWK has no non-public
knowledge of any transmission expansion or other similar projects that, in
NIAGARA MOHAWK's opinion, is reasonably likely to materially impact the transfer
capability of the transmission interface in New York State commonly known as the
Total East Interface.

            5.1.2    NIAGARA MOHAWK and PRODUCER acknowledge and agree that,
subject to the provisions of the NYISO OATT, as applicable, PRODUCER may obtain
any

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                 Substitute Original Sheet No. 9
Rate Schedule FERC No. 178                     Superceding Original Sheet Nos. 9

transmission service(s) from the NYISO pursuant to the NYISO OATT at any time
without affecting the services provided hereunder.

      5.2    Reserved for future use.

      5.3    NIAGARA MOHAWK's obligation to provide PRODUCER with transmission
services as described in Section 5.1.1 is subordinate to and subject to NIAGARA
MOHAWK's obligations under the New York Public Service Law to serve its own
retail customers, its obligations to its firm wholesale and transmission
customers under agreements entered into prior to the date of this AGREEMENT and
its obligations under the New York Power Pool Agreement, all as may be amended
from time to time. Niagara Mohawk shall have the right, in its sole discretion,
to modify the level of service under agreements entered into prior to the date
of this AGREEMENT, provided that NIAGARA MOHAWK's ability to provide PRODUCER
with the level of transmission services described in this AGREEMENT is not
reduced in any way. In addition, NIAGARA MOHAWK shall have the right in its sole
discretion to take such actions, including curtailment of services to PRODUCER
under this AGREEMENT prior to the implementation of voltage reduction, or any
other actions necessary to maintain reliable electric service in accordance with
NIAGARA MOHAWK's operating policies and GOOD UTILITY PRACTICE. In the event of
such curtailment NIAGARA MOHAWK shall not be held liable for any losses or
damages which PRODUCER may incur as a result; provided such curtailment shall
continue only for so long as it is reasonably necessary under NIAGARA MOHAWK's
operating policies and GOOD UTILITY PRACTICE.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 10
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 10

      5.4    PRODUCER shall schedule and deliver all electricity delivered
pursuant to this AGREEMENT with the NYISO, pursuant to the scheduling and
delivery provisions of the NYISO OATT. PRODUCER shall be subject, with respect
to such deliveries, to any rates, charges and penalties properly assessed by the
NYISO pursuant to the scheduling and delivery provisions of the NYISO OATT,
including, without limitation, all congestion rents assessed in accordance with
Section 4.3 of Attachment K of the NYISO OATT, unless the NYISO OATT is amended
to make such charges inapplicable to PRODUCER, but excluding, without
limitation, any and all charges associated with Ancillary Services Schedules 1-6
of the NYISO OATT and the NYPA Transmission Adjustment Charge of the NYISO OATT,
unless the NYISO OATT is specifically amended subsequent to June 29, 2001 to
make such charges applicable to transmission services furnished to the PRODUCER
under this AGREEMENT; provided however, that PRODUCER retains its rights under
the Federal Power Act to challenge and oppose any such amendments to the NYISO
OATT.

              PRODUCER shall be responsible for the cost of the computer
system and interface necessary to accommodate the scheduling function for the
ELECTRICITY to be transmitted under this agreement. Such computer system and
associated interface shall be installed by PRODUCER in accordance with NIAGARA
MOHAWK's specifications, as provided for in ESB #756-B.

      5.5     Reserved for future use.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 11
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 11

      5.6    The parties expressly acknowledge and agree that PRODUCER has
exercised its right to convert its transmission rights in this AGREEMENT to
GRANDFATHERED TCCs (as defined in the NYISO OATT), pursuant to Section 4 of
Attachment K of the NYISO OATT.

6.    METERING REQUIREMENTS

      6.1    Metering requirements for services provided under this AGREEMENT
shall be as provided in the Interconnection Agreement.

7.    DEPOSIT: PAYMENT FOR THE USE OF TRANSMISSION FACILITIES; PROGRESS REPORTS

      7.1    On the earlier of either (i) the date eighteen (18) months after
execution of this Agreement; or (ii) the fifth business day to occur after the
date an which the funds necessary to construct, own, operate and maintain the
PRODUCTION FACILITY described in Section 1.1 first become available to PRODUCER,
PRODUCER shall post with NIAGARA MOHAWK a refundable, interest-bearing deposit
in the form of cash or in the alternative, an irrevocable letter of credit
(hereinafter referred to as an "LOC") for the amount as specified by the rate
defined in Schedule D (hereinafter referred to as the "DEPOSIT"). In the event
the DEPOSIT is made in cash, NIAGARA MOHAWK shall hold such cash in an
interest-bearing escrow account with Marine Midland Bank, N.A., or another bank
chosen by NIAGARA MOHAWK and reasonably acceptable to PRODUCER and invest it in
the Certificate of Deposit or U.S. Treasury Bill of the PRODUCER's choice;
provided, however, the instrument must mature on or before the scheduled
COMMERCIAL OPERATION DATE of the PRODUCTION FACILITY. In the

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 12
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 12

event the DEPOSIT made is in the form of an LOC, such LOC must be from a
financial institution rated at least AA and must be maintained for a term that
extends ten (10) days past the scheduled date of the COMMERCIAL OPERATION DATE
of the PRODUCTION FACILITY. Failure of the PRODUCER to post the DEPOSIT in
accordance with this Section 7.1 shall render this AGREEMENT null and void at
the option of NIAGARA MOHAWK or PRODUCER. If, after posting the DEPOSIT,
PRODUCER fails to enter into a loan or credit agreement (hereinafter referred to
as the "FINANCIAL CLOSING") for the financing of the construction and/or
permanent financing of the PRODUCTION FACILITY with one or more financial
institutions (hereinafter referred to as the "LENDERS") within the following
eight (8) months, either party may terminate this AGREEMENT upon thirty days
prior written notice and in such event NIAGARA MOHAWK shall retain the DEPOSIT
(less interest, if any) without further obligation to PRODUCER; provided,
however, that PRODUCER may extend such eight (8) month period, on a month by
month basis up to a maximum of twelve (12) months, by paying NIAGARA MOHAWK on
the first business day of each month following the expiration of such eight (8)
month period, a nonrefundable amount equal to one-twelfth (1/12) of the rate per
KW of Contract Demand as specified in Schedule D. In addition, the deadline for
FINANCIAL CLOSING, shall be extended for up to twelve month-by-month periods
upon a demonstration by PRODUCER to NIAGARA MOHAWK'S reasonable satisfaction
that an event of force majeure (as defined in Section 20.1) has delayed the
commencement of construction by at least the length of time of such extension.
In the event that NIAGARA MOHAWK does not reasonably concur that such event of
force majeure has occurred, no such extensions shall be granted.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 13
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 13

            Provided that the PRODUCER meets the COMMERCIAL OPERATION DATE not
later than forty-eight (48) months after FINANCIAL CLOSING, as such date may be
extended in accordance with the provisions of the following two paragraphs or
due to NIAGARA MOHAWK'S failure to complete construction of any systems upgrade
facilities as may be required under the Interconnection Agreement, the DEPOSIT
plus interest (if any) shall be returned to the PRODUCER within thirty (30) days
from the achievement of the COMMERCIAL OPERATION DATE.

            In the event that PRODUCER fails to-meet the COMMERCIAL OPERATION
DATE within forty-eight (48) months of the FINANCIAL CLOSING, NIAGARA MOHAWK may
terminate this AGREEMENT upon thirty days prior written notice and retain the
DEPOSIT (less interest, if any) without further obligation to PRODUCER;
provided, however, that PRODUCER may extend such forty-eight (48) month period,
on a month by month basis up to a maximum of twelve (12) months, by paying
NIAGARA MOHAWK on the first business day of each month following the expiration
of such forty-eight (48) month period a non-refundable amount equal to
one-twelfth (1/12) the rate specified in Schedule B per kilowatt of Contract
Demand.

            In addition, the deadline for the COMMERCIAL OPERATION DATE shall be
extended for up to twelve month-by-month periods upon a demonstration by
PRODUCER to NIAGARA MOHAWK'S reasonable satisfaction that an event of force
majeure (as defined in Section 20.1) has delayed the COMMERCIAL OPERATION DATE
by at least the length of

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 14
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 14

time of such extension. In the event that NIAGARA MOHAWK does not reasonably
concur that such event of force majeure has occurred, no such extensions shall
be granted.

      7.2    For services rendered pursuant to Section 5.1.1, NIAGARA MOHAWK
shall bill PRODUCER on or before the tenth (l0th) day of the month following the
month in which services were rendered. PRODUCER shall pay NIAGARA MOHAWK on the
first banking day common to the parties hereto following the nineteenth (19th)
day of the month in which the bills are rendered. If any amount billed PRODUCER
by NIAGARA MOHAWK remains unpaid for a period of sixty (60) days or more after
the date due under this AGREEMENT, NIAGARA MOHAWK shall have the right upon no
less than thirty (30) days' prior written notice to PRODUCER (i) to discontinue
providing service to PRODUCER for nonpayment of bills and to refuse to resume
provision of service so long as any part of the amount due, including interest,
remains unpaid; or (ii) to terminate this AGREEMENT, if the amount due,
including interest, is not paid during such thirty (30) day period. Any LENDER
shall have the right, in its sole discretion and without obligation, to prevent
such termination by making any such payment on PRODUCER's behalf within the
relevant period.

      7.3    In the event of a dispute as to the amount of any bill, PRODUCER
shall notify NIAGARA MOHAWK in writing of the amount in dispute and PRODUCER
shall pay to NIAGARA MOHAWK the total bill including the disputed amount.
NIAGARA MOHAWK shall refund to PRODUCER, with interest at the rate of one and
one-half (1.5) percent per month from the date such payment was made, any
portion of the disputed amount ultimately found to be improper.

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<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 15
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 15

      7.4    Payments will be made by wire transfer to a bank specified by
NIAGARA MOHAWK. Amounts overdue will be charged monthly interest at one and
one-half (1.5) percent per month on the amount that is overdue calculated from
the due date until the day of payment.

      7.5    PRODUCER shall send NIAGARA MOHAWK complete copies of the progress
reports regarding the development of the PRODUCTION FACILITY which it sends to
PURCHASER at the time such material is mailed to PURCHASER. Promptly after
execution of this AGREEMENT all copies of such progress reports sent to
PURCHASER prior to the date of execution of this AGREEMENT shall be sent to
NIAGARA MOHAWK, provided that PRODUCER may delete any and all information in
such reports not relating to transmission and interconnection matters.

8.    FUTURE RATE CHANGES

      8.1    Nothing contained herein shall be construed as affecting in any way
either NIAGARA MOHAWK's right under this rate schedule to unilaterally make
application to the FERC or any other appropriate regulatory authority having
jurisdiction over the transactions provided the PRODUCER hereunder, for a change
in rates under Section 205 of the Federal Power Act and pursuant to FERC's Rules
and Regulations promulgated thereunder, or any other applicable statute or
regulations, or PRODUCER's right to challenge such application.

      8.2    The PRODUCER and NIAGARA MOHAWK expressly acknowledge and agree
that the firm transmission rate in the AGREEMENT shall be fixed at
$1.76/kW/month for the period commencing on July 2, 1999 and ending on December
31, 2005 and that no change may

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 16
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 16

be made to this firm transmission rate during such period except as required by
the FERC pursuant to the public interest standard in Section 206 of the Federal
Power Act. NIAGARA MOHAWK and PRODUCER waive their rights to seek changes to the
firm transmission rate in the AGREEMENT for the period described in the previous
sentence pursuant to Sections 205 and 206 of the Federal Power Act; provided
that nothing contained in this provision shall constitute a waiver of any of the
PRODUCER's or NIAGARA MOHAWK's rights in this AGREEMENT or in the
Interconnection Agreement, including under Section 205 or Section 206 of the
Federal Power Act, except as expressly set forth in this sentence.

9.    COMPENSATION FOR LOSSES

      9.1    PRODUCER shall compensate NIAGARA MOHAWK for losses incurred by
NIAGARA MOHAWK in its control area and NIAGARA MOHAWK shall compensate PRODUCER
for losses avoided by NIAGARA MOHAWK in its control area as a result of NIAGARA
MOHAWK's provision of transmission services hereunder. The determination of such
losses and the procedure for compensation thereof shall be determined by NIAGARA
MOHAWK's Power Control Department in accordance with NIAGARA MOHAWK's practices
relating to other similar transactions and in accordance with GOOD UTILITY
PRACTICE.

      9.2    Notwithstanding the foregoing provisions in Section 9.1, effective
as of September 1, 2000, and so long as transmission losses continue to be
provided by the NYISO: (i) PRODUCER agrees to compensate the NYISO for
transmission losses associated with transmission services provided hereunder, in
accordance with Section 4.3 of Attachment K to the

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 17
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 17

NYISO OATT; and (ii) NIAGARA MOHAWK agrees not to assess PRODUCER any rate,
cost, charge or any other expense for transmission losses under this AGREEMENT.

10.   INDEMNIFICATION. INSURANCE, DAMAGE LIMITATION

      10.1    Each party hereto respectively assumes full responsibility in
connection with the transmission services provided hereunder on its side of the
POINT OF RECEIPT and for the wires, apparati, devices and appurtenances used in
connection therewith. Each party shall indemnify, save harmless and defend the
other against all third party claims, demands, costs or expenses for loss,
damage or injury to person or persons or property in any manner directly or
indirectly arising from, connected with or growing out of the generation,
transmission or use of energy by it on its side of the POINT OF RECEIPT or for
the operation of switching equipment in connection with said delivery; provided,
however, that each party shall be liable for all claims of the party's own
employees arising out of any provision of the Workers' Compensation Law.

      10.2    Each party agrees to maintain Workers' Compensation and Employers'
Liability Insurance covering their respective employees as required by law.
PRODUCER agrees to provide and maintain public liability insurance, including
contractual coverage, with respect to the PRODUCTION FACILITY with one or more
reputable insurance companies rated by Best's with not less than a B+ rating.
The minimum limits of liability shall be:

                  Bodily injury - $2,000,000 each occurrence

                  Property Damage - $1,000,000 each occurrence

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 18
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 18

                  or a minimum combined single limit of:

                  $2,500,000 each occurrence

      10.3    Prior to the FINANCIAL CLOSING, PRODUCER shall provide NIAGARA
MOHAWK with copies of Certificates of Insurance for all coverages required
herein. All such Certificates shall show that the policy shall not be cancelled,
nor material change made in the coverages provided thereunder until not less
than thirty (30) days prior written notice has been given to the PRODUCER. Such
Certificates shall show expiration dates of insurance coverages. PRODUCER shall
notify NIAGARA MOHAWK immediately of any cancellation or material change in
coverage.

      10.4    Subject to Section 10.1 and except for any loss, damage, claim,
cost, charge or expense resulting from the grossly negligent, reckless or
willful misconduct of either party, its directors or members of its governing
bodies, officers or employees, neither party shall be liable to the other party
for incidental, punitive, special, indirect or consequential damages connected
with or resulting from the performance or nonperformance of this AGREEMENT or
arising from breach of this AGREEMENT. Except as provided in the foregoing
sentence, each party releases the other party, its directors or members of its
governing bodies, officers and employees from any such liability, claim or
action arising from damage to its property due to the performance of this
AGREEMENT.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 19
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 19

      10.5    PRODUCER shall not execute, levy or otherwise enforce a judgment
for liability under Section 10.4, including recording or effecting a judgment
lien against NIAGARA MOHAWK'S directors or members of its governing bodies,
officers and employees.

      10.6    The provisions of this Article shall survive the termination of
this AGREEMENT.

11.   ASSIGNMENT; BINDING EFFECT AND GOVERNING LAW

      11.1    Except as otherwise provided in this Article 11, neither party
shall assign, pledge or otherwise transfer this AGREEMENT or any right or
obligation under this AGREEMENT, by operation of law or otherwise, without first
obtaining the other party's written consent, which consent shall not be
unreasonably withheld. Notwithstanding the foregoing, PRODUCER may, without the
prior written consent of NIAGARA MOHAWK, from time to time, assign or resell to
any third party ("ASSIGNEE") that is (i) an electric utility (including NIAGARA
MOHAWK and any power marketer), (ii) a Federal power marketing agency, or (iii)
any person generating electric energy for sale for resale, all or any portion of
GRANDFATHERED TCCs assigned to PRODUCER by the NYISO; provided that PRODUCER
complies with all applicable provisions of the NYISO OATT, that PRODUCER retains
and pays for the transmission capacity associated with such assigned TCCs under
this AGREEMENT, and that PRODUCER notifies NIAGARA MOHAWK of the scope and
duration of any such assignment; and provided further that PRODUCER shall not be
relieved of its obligations with respect to any of the rights assigned hereunder
without the prior written consent of NIAGARA MOHAWK, which consent shall not

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 20
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 20

be unreasonably withheld or delayed. ASSIGNEE will receive, for the term of any
such assignment, all of the rights under the AGREEMENT and the NYISO OATT given
to PRODUCER in its capacity as holder of the TCCs in question. PRODUCER shall
also have the right to assign all or any portion of PRODUCER's GRANDFATHERED
TCCs through the CENTRALIZED TCC AUCTION or SECONDARY MARKETS for TCCs (as both
of those terms are defined in the NYISO OATT), or any other markets made
available for the sale of PRODUCER's GRANDFATHERED TCCs. The parties expressly
acknowledge and agree that PRODUCER shall have all rights to the revenues from
PRODUCER's exercise of its assignment of its GRANDFATHERED TCCs, and that
NIAGARA MOHAWK shall not have any right or claim to any part of such revenues.

      11.2    Upon thirty (30) days prior written notice to NIAGARA MOHAWK,
PRODUCER may, without the consent of NIAGARA MOHAWK, assign its interests in
this AGREEMENT, in whole or in part, to (a) LENDERS or any successor to such
LENDERS; or (b) an entity controlling, controlled by, or under common control
with PRODUCER ("Affiliate"); provided, however, that in each such case, such
assignment shall not relieve PRODUCER of its obligations under this AGREEMENT,
unless the assignee shall expressly assume all of PRODUCER's obligations under
this AGREEMENT. If LENDERS or any successor to such LENDERS succeed to the
interest of PRODUCER in this AGREEMENT by foreclosure or otherwise, NIAGARA
MOHAWK shall accord such LENDERS or any successor to such LENDERS, their
successors and assigns, the same rights as PRODUCER hereunder. In connection
with the FINANCIAL CLOSING, NIAGARA MOHAWK agrees to execute, and deliver and to
furnish a written consent to the assignment by PRODUCER of this AGREEMENT

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 21
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 21

to the LENDERS, a certificate of an authorized officer to NIAGARA MOHAWK and an
opinion of counsel to NIAGARA MOHAWK, in each case in form and substance
reasonably acceptable to the LENDERS and NIAGARA MOHAWK.

      11.3    Any company or entity which shall succeed by purchase, merger or
consolidation to the properties, substantially or entirely, of either NIAGARA
MOHAWK or PRODUCER, as the case may be, shall be entitled to the rights and
shall be subject to the obligations of its predecessor in title under this
AGREEMENT provided that, at least thirty (30) days prior to the effective date
of the proposed assignment, the assignee shall unconditionally assume, and agree
to be bound by, all of the terms and conditions of this AGREEMENT, and the
assignee makes certain additional representations and warranties as appropriate
for assignee as contained in Article 2.

      11.4    This AGREEMENT shall be governed by the laws of the State of New
York.

12.   EXECUTION IN COUNTERPARTS

      12.1    This AGREEMENT may be executed in several counterparts, each of
which shall be an original and all of which shall constitute but one and the
same instrument.

13.   WAIVER

      13.1    No delay or omission in the exercise of any right under this
AGREEMENT shall impair any such right or shall be taken, construed or considered
as a waiver or relinquishment thereof, but any such right may be exercised from
time to time as often as may be deemed

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 22
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 22

expedient. In the event that any agreement or covenant herein shall be breached
and the breach thereafter waived, such waiver shall be limited to the particular
breach so waived and shall not be deemed to waive any other breach hereunder.
The rights provided herein are cumulative and exclusive of any remedies provided
by law.

14.   COMPLETE AGREEMENT

      14.1    Except as provided in Articles 4, 7 and 8, this AGREEMENT is
exclusive and contains all of the terms of the agreement between the parties and
no change or variation in this AGREEMENT may be made except in express terms and
by an instrument in writing signed by the parties hereto.

      14.2    Subject to FERC acceptance as provided in Section 17.2, if any
provision hereof is invalid or unenforceable in any jurisdiction, to the fullest
extent permitted by law, the other provisions hereof shall remain in full force
and effect in such jurisdiction and shall be construed in order to carry out the
intentions of the parties as nearly as possible.

15.   DISPUTES

      15.1    In the event of any dispute under this AGREEMENT, either party may
make application to an appropriate administrative or judicial authority or body
for relief.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 23
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 23

16.   NOTICES

      16.1    All written notifications pursuant to this AGREEMENT shall be in
writing and shall be personally delivered or mailed by certified or registered
first class mail, return receipt requested, as follows:

To NIAGARA MOHAWK                       To PRODUCER:
MANAGER-TRANSMISSION CONTRACTS          General Manager
NIAGARA MOHAWK POWER CORPORATION        Sithe/Independence Power
300 Erie Boulevard West                      Partners, L.P.
Syracuse, New York  13202               c/o Sithe/Independence, Inc.
                                        P.O. Box 1046
                                        76 Independence Way
                                        Oswego, New York  13126

                                        and

                                        Sithe Energies, Inc.
                                        335 Madison Ave.
                                        28th Floor
                                        New York, New York  10017
                                        Attn: General Counsel

            Either party may change its address for notices by notice to the
other in the manner provided above.

17.   TERM OF AGREEMENT

      17.1    NIAGARA MOHAWK shall file this AGREEMENT for approval with the
FERC under Section 205 of the Federal Power Act and pursuant to the FERC's Rules
and Regulations promulgated thereunder. NIAGARA MOHAWK shall file this AGREEMENT
for approval with the FERC within twenty (20) days of receipt of the executed
AGREEMENT from PRODUCER.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 24
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 24

All filing fees for the initial filing of this AGREEMENT and for any subsequent
filings with FERC or other regulatory or judicial authorities for the approval
or effectiveness of this AGREEMENT shall be paid by PRODUCER. NIAGARA MOHAWK
shall pay any filing fees in connection with any other filing by it including
any filing under Article 8 hereof.

      17.2    This AGREEMENT shall not be effective until it has been accepted
or approved by FERC, whichever occurs first. Upon such effectiveness, this
AGREEMENT shall continue for a period of twenty (20) years from the COMMERCIAL
OPERATION DATE of the PRODUCTION FACILITY. In the event FERC should initially
permit this AGREEMENT to become effective subject to further proceedings and
pursuant to those proceedings FERC does not accept or materially modifies this
AGREEMENT, the parties shall modify this AGREEMENT to carry out their original
intentions as nearly as possible.

      17.3    PRODUCER shall notify NIAGARA MOHAWK in writing thirty (30) days
prior to the anticipated date of initial operation of the PRODUCTION FACILITY.
PRODUCER shall then confirm the COMMERCIAL OPERATION DATE within ten (10) days
after its actual occurrence.

      17.4    If (i) the Power Purchase Agreement should terminate prior to the
expiration of this AGREEMENT or (ii) for any other reason, PRODUCER is unable to
continue development or operation of the PRODUCTION FACILITY, PRODUCER may
terminate this AGREEMENT effective thirty (30) days after written notice to
NIAGARA MOHAWK without further obligation to NIAGARA MOHAWK except as set forth
in Section 17.5 below.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 25
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 25

      17.5    Applicable provisions of this AGREEMENT shall continue in effect
after termination to the extent necessary to provide for final billings and
adjustments and as may be otherwise required to carry out the intent of the
parties as expressed in this AGREEMENT.

18.   DEFAULT OR BREACH OF CONTRACT

      18.1    Except as otherwise provided in Sections 7.1 and 7.2, in the
event of a material default or breach of any provision of this AGREEMENT, where
such default or breach shall have continued for and not been cured within sixty
(60) days after receipt of a written notice from the non-breaching party
specifying in reasonable detail the nature of such default or breach, the
non-breaching party may by written notice terminate the AGREEMENT at the end of
the next succeeding calendar month; provided however, that if such default or
breach cannot be reasonably cured within such sixty (60) day period, the
breaching party shall be entitled to an additional period of time to cure the
breach, as may be reasonable under the circumstances; provided that the
breaching party commences efforts to cure within the initial sixty (60) day
period and diligently pursues cure thereafter. Any LENDER shall have the right,
in its sole discretion and without obligation, to prevent such termination by
curing any such default or breach on PRODUCER'S behalf within the relevant
period. If the AGREEMENT is terminated, NIAGARA MOHAWK shall give the FERC
notice of such termination as is required by regulation.

      18.2    Termination of this AGREEMENT for breach or default shall not
relieve the breaching party of any of its liabilities and obligations hereunder,
and the non-breaching party may take whatever judicial or administrative actions
as appear necessary or desirable to enforce

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 26
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 26

its rights hereunder. The rights specified herein shall be in addition to all
other remedies available to NIAGARA MOHAWK or the PRODUCER, either at law or in
equity, for default or breach of any provision of this AGREEMENT.

19.   RELATIONSHIP OF PARTIES

      19.1    Nothing contained in this AGREEMENT shall be construed as causing
PRODUCER and NIAGARA MOHAWK to be partners, joint venturers, employer and
employee or principal and agent. Neither party shall have any authority to
create or assume in the other party's name or on its behalf any obligation,
express or implied, or to act or purport to act as the other party's agent or
legally empowered representative for any purpose whatsoever. Neither party shall
be liable to any third party in any way for any engagement, obligation,
commitment, contract, representative or for any negligent act or omission to act
of the other party except as expressly provided for herein.

20.   FORCE MAJEURE

      20.1    Except as provided in Section 7.1, neither party shall be
considered to be in default or breach hereunder, and each party shall be excused
from performance hereunder, if and to the extent that it shall be delayed in or
prevented from performing or carrying out any provision of this AGREEMENT by
reasons of or through storm, flood, lightning strikes, earthquake, fire, ice,
epidemic, war, invasion, riot, civil disturbance, sabotage, explosion,
insurrection, military or usurped power, strikes, stoppage of labor, labor
dispute, failure of contractors or suppliers of material, action of any court or
public authority, or any civil or

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 27
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 27

military authority de facto or de jure, change in law, act of God or the public
enemy, or any other cause reasonably beyond such party's control including,
without limitation, disconnection or limited operation of the PRODUCTION
FACILITY, the INTERCONNECTION FACILITY or NIAGARA MOHAWK's electric system due
to failure of facilities or unscheduled repairs/maintenance. The party claiming
force majeure shall use due diligence to resume the provision of service
hereunder as soon as practicable. Neither party shall be liable to the other
party for or on account of any loss, damage, injury or expense, including but
not limited to incidental, punitive, special, indirect or consequential damages
resulting from or arising out of such delay or inability to perform.

21.   HEADINGS

      21.1    Article headings in this AGREEMENT are included herein for
convenience of reference only and shall not constitute a part of this AGREEMENT
for any other purpose.

              IN WITNESS WHEREOF the parties hereto have caused this instrument
to be executed as of the day and year first above written.

                            [SIGNATURE PAGES FOLLOW]

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on:June 29, 2001
</Table>

<PAGE>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 27
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 27

SITHE/INDEPENDENCE POWER PARTNERS, L.P.

By:  Sithe/Independence, Inc., its General Partner

By:        /s/ Martin B. Rosenberg
         --------------------------------------------
Title:   Senior Vice President

Date:   June 29, 2001

Niagara Mohawk Power Corporation

By:        /s/ Edward J. Dienst
         --------------------------------------------
Title:   Senior Vice President

Date:   June 29, 2001

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 28
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 28

                                   SCHEDULE A

                        NIAGARA MOHAWK POWER CORPORATION

                                FIRM TRANSACTIONS

                     853 MW of firm power (CONTRACT DEMAND).

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 29
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 29

                                   SCHEDULE B

                        NIAGARA MOHAWK POWER CORPORATION

                       RATE FOR FIRM TRANSMISSION SERVICE

       EFFECTIVE UPON SYNCHRONIZATION TO NIAGARA MOHAWK'S ELECTRIC SYSTEM

       For Firm Contract Demand Deliveries               $ 1.76/kw/Mo.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 30
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 30

                                   SCHEDULE C

                            Reserved for future use.

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation                Substitute Original Sheet No. 31
Rate Schedule FERC No. 178                    Superceding Original Sheet Nos. 31

                                   SCHEDULE D

                        NIAGARA MOHAWK POWER CORPORATION

                                RATE FOR DEPOSIT

      NIAGARA MOHAWK's rate for the deposit to be posted as payment for the use
      of transmission facilities.

                                                     $5.00/kw of CONTRACT DEMAND

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table>

<Page>

Niagara Mohawk Power Corporation            Substitute Original Sheet No. 32-52
Rate Schedule FERC No. 178                Superceding Original Sheet Nos. 32-52

                             RESERVED FOR FUTURE USE

<Table>
<S>                                                           <C>
Issued by: Susan L. Hodgson                                    Effective Date:  July 1, 2001
           Manager- Transmission and Delivery Services
           Issued on: June 29, 2001
</Table><Page>

                                                                  Exhibit 10.5.4

                            UNITED STATES OF AMERICA
                                   BEFORE THE
                      FEDERAL ENERGY REGULATORY COMMISSION

Sithe/Independence Power Partners, L.P. )
                                        )
         v.                             )        Docket Nos. EL99-65-000
                                        )                    EL95-38-000
Niagara Mohawk Power Corporation        )                    (not consolidated)

                              SETTLEMENT AGREEMENT
                                 (JUNE 28, 2001)

      SECTION I. INTRODUCTION

      1. Niagara Mohawk Power Corporation ("Niagara Mohawk") is an electric
utility in New York State providing transmission services in interstate commerce
subject to the Commission's jurisdiction under the Federal Power Act ("the
FPA").

      2. Sithe/Independence Power Partners, L.P. ("Sithe") is the owner and
operator of a 1060 MW gas-fired electric generating facility located in Scriba,
New York ("the Independence Plant"). Prior to September 1, 2000, Sithe sold the
majority of the electricity produced at its Independence Plant to the
Consolidated Edison Company of New York, Inc. ("Con Edison").

      3. Sithe and Niagara Mohawk are parties to a transmission service
agreement with Niagara Mohawk dated November 5, 1991 (as amended, the "TSA") and
an interconnection agreement dated March 9, 1992 (as amended, the "IA"). The TSA
was initially accepted for filing by the Commission on February 5, 1992, as
Niagara Mohawk's Rate Schedule No. 178. The IA was initially accepted for filing
by the Commission on October 29, 1993, as Niagara Mohawk's Rate Schedule No.
189.
<Page>

      SECTION II. PROCEDURAL HISTORY

      1. In March of 1995, Sithe filed a complaint against Niagara Mohawk
under Section 206 of the FPA, which complaint was assigned Docket No.
EL95-38-000 by the Commission. In that complaint, Sithe claimed that Niagara
Mohawk's methodology for calculating transmission losses under the TSA was
unjust, unreasonable and unduly discriminatory. On May 10, 1995, Niagara
Mohawk filed an answer to Sithe's complaint, denying Sithe's claims that
Niagara Mohawk was calculating transmission losses under the TSA pursuant to
a methodology that was unjust, unreasonable or unduly discriminatory. On
September 16, 1996, the Commission issued an order denying Sithe's complaint
in SITHE/INDEPENDENCE POWER PARTNERS, L.P. V. NIAGARA MOHAWK POWER CORP., 76
FERC [Paragraph] 61,285 (1996). The Commission denied rehearing of the
September 16, 1996 order in SITHE/INDEPENDENCE POWER PARTNERS, L.P. V.
NIAGARA MOHAWK POWER CORP., 81 FERC [Paragraph] 61,071 (1997).

      2. On December 16, 1997, Sithe petitioned the United States Court of
Appeals for the District of Columbia Circuit ("Court") for review of the
Commission's two orders. On January 29, 1999, the Court issued an opinion
granting Sithe's petition for review and remanding the proceeding to the
Commission. SITHE/INDEPENDENCE POWER PARTNERS V. FEDERAL ENERGY REGULATORY
COMM'N, 165 F.3d 944, 949 (D.C. Cir. 1999). On April 30, 1999, Sithe filed a
Motion for Further Proceedings on Remand in Docket No. EL95-38-000. On May 17,
1999, Niagara Mohawk filed an answer to Sithe's Motion, requesting the
Commission to reaffirm its prior orders denying Sithe's Complaint. This
Settlement

                                       2
<Page>

Agreement ("Settlement") fully resolves the issues raised by Sithe's
complaint in Docket No. EL95-38-000.

      3. On May 3, 1999, Sithe filed another complaint against Niagara Mohawk
under Section 206 of the FPA. This second complaint ("the Complaint") was
assigned Docket No. EL99-65-000 by the Commission. This Settlement also fully
resolves the issues raised in this Complaint.

      4. In the Complaint, Sithe claimed that both the transmission rates
established in Rate Schedule No. 178 and loss rates contained in that Rate
Schedule were unjust and unreasonable. Sithe also sought a refund or reduction
in future rates of approximately $63 million for certain expenditures made by
Sithe for facilities constructed by Sithe and transferred to Niagara Mohawk or
constructed by Niagara Mohawk and paid for by Sithe. Sithe requested this refund
or reduction in future rates on the ground that the facilities to which those
payments related were allegedly improvements to Niagara Mohawk's transmission
system rather than the kind of generator leads or interconnection facilities
which could be charged to Sithe under applicable Commission pricing policies. In
addition, Sithe also sought a variety of changes to the provisions of both the
TSA and the IA. In each sentence of this paragraph, the relief sought by Sithe
is as more particularly described in the Complaint.

      5. On June 16, 1999, Niagara Mohawk filed its Answer to the Complaint. In
its Answer, Niagara Mohawk contended that the transmission and loss rates
established in the TSA were in all respects just and reasonable. Niagara Mohawk
also denied Sithe's claim that Niagara Mohawk had required Sithe to pay for any
upgrades to Niagara

                                       3
<Page>

Mohawk's transmission system in violation of Commission pricing policies and
opposed the changes to the provisions of the TSA and the IA requested by Sithe.

      6. On July 1, 1999, Sithe filed a Response to Niagara Mohawk's Answer to
the Complaint.

      7. On September 27, 2000, the Commission issued its Order on Complaint
Establishing Hearing and Settlement Judge Procedures. NIAGARA MOHAWK POWER
CORPORATION, 97 FERC [Paragraph] 61,258 (2000) ("September 27 Order"). In the
September 27 Order, the Commission set for hearing Sithe's challenges to the
transmission rate and loss rates contained in the TSA and Sithe's request for
a refund of approximately $63 million for transmission facilities provided to
Niagara Mohawk or constructed by Niagara Mohawk at Sithe's expense.

      8. On October 27, 2000, Niagara Mohawk filed an Application for Rehearing
of the portion of the September 27 Order setting for hearing Sithe's claim for a
refund of approximately $63 million for transmission facilities provided to
Niagara Mohawk by Sithe or constructed by Niagara Mohawk at Sithe's expense. On
November 13, 2000, Sithe filed an Answer to this rehearing request. By order
dated November 15, 2000, the Commission granted rehearing for the purpose of
further consideration of the issues raised in Niagara Mohawk's rehearing
request.

      9. By order dated October 4, 2000, the Commission's Chief Administrative
Law Judge assigned the Honorable Carmen A. Cintron to act as Settlement Judge in
these proceedings. A settlement conference was held at the Commission's offices
on November 14, 2000 and numerous subsequent meetings and telephone
conversations have been conducted between the parties and with Judge Cintron.
These negotiations

                                       4
<Page>

have resulted in this Settlement, which resolves all issues in Docket Nos.
EL99-65-000 and EL95-38-000.

      SECTION III. TERMS OF THE SETTLEMENT

      1. Niagara Mohawk and Sithe (collectively referred to herein as "the
Sponsoring Parties") have agreed to this Settlement resolving all issues in
Docket Nos. EL99-65-000 and EL95-38-000.

      2. Sithe has previously consented in Docket Nos. ER97-1523-011, ET AL., to
the application of the marginal loss provisions of the NYISO OATT to service
received by Sithe under the TSA after August 31, 2000. The Sponsoring Parties
stipulate and agree that: (a) as full compensation to Sithe for claims by Sithe
for overcharges for transmission losses during the period from July 2, 1999 to
November 17, 1999, Niagara Mohawk has paid Sithe a lump-sum payment in an amount
equal to $2,300,000.00; and (b) Niagara Mohawk made this payment to Sithe on
March 2, 2001. The Sponsoring Parties agree that issues relating to transmission
losses during the period from November 18, 1999 to August 31, 2000 shall be
finally determined in Docket Nos. ER97-1523-011, ET AL.

      3. The Sponsoring Parties stipulate and agree that the TSA will be amended
and restated as provided in Attachment A to this Settlement to provide that the
currently effective firm transmission rate of $1.76/kW/month and the currently
effective Contract Demand of 853 MW shall be fixed for a period commencing on
July 2, 1999 and ending December 31, 2005, and to further provide that no change
may be made to the transmission rate during this period except as required by
the Commission pursuant to the public interest standard of Section 206 of the
FPA. To this end, Niagara Mohawk and

                                       5
<Page>

Sithe each waive their rights to seek changes to the firm transmission rate
established by this Settlement pursuant to Sections 205 and 206 of the FPA
during this period; provided however that nothing in this Settlement shall
constitute a waiver of any of the Sponsoring Parties' rights under the TSA or
the IA, including under Sections 205 or 206 of the FPA, except as expressly set
forth in this sentence and in Sections 5.1.1 and 8.2 of the TSA.

      4. In order to settle Sithe's interconnection and transmission upgrade
claims in Docket No. EL99-65-000: (a) Niagara shall pay to Sithe an amount equal
to $28,112,917.00 ("Purchased Facilities Payment") to purchase the facilities
identified in Attachment C to this Settlement ("Purchased Facilities"); (b) The
Sponsoring Parties acknowledge and agree that, as of the date of the execution
of this Settlement, the Purchased Facilities are transmission upgrade facilities
that are integrated with the Niagara Mohawk transmission system; (c) The
Sponsoring Parties agree that the Purchased Facilities Payment is intended to
represent the full fair-market value, as determined by the Sponsoring Parties,
of the Purchased Facilities as of the date of this Settlement, and that,
accordingly, Niagara Mohawk believes (and will use its best efforts, consistent
with its obligations under federal and state law, not to take any position
inconsistent therewith) that neither Sithe's original payment for the Purchased
Facilities nor the Purchased Facilities Payment will give rise to federal or
state tax liability to Niagara Mohawk; (d) The Purchased Facilities Payment
shall be made in two lump-sum payments to Sithe, and Commission acceptance or
approval of this Settlement shall constitute authorization to Niagara Mohawk to
reflect this payment on its books as a capital payment appropriately made for
transmission facilities with a fair market value of $28,112,917.00; and (e)
Niagara Mohawk has already paid Sithe $15,075,000.00 of the

                                       6
<Page>

Purchased Facilities Payment, on March 2, 2001, and shall pay to Sithe, by no
later than August 1, 2001, the remaining $13,037,917.00 of the Purchased
Facilities Payment (the "Remaining Portion").

      5. The Sponsoring Parties stipulate and agree that it is appropriate to
assign directly to Sithe those costs already incurred by Sithe prior to the date
of this Settlement, for the facilities identified in Attachment D to this
Settlement (the "Other Facilities"). Sithe agrees to waive its right to make
filings at the Commission under Section 206 of the Federal Power Act to: (i)
seek reimbursement from Niagara Mohawk for all, or any part of, the costs and/or
expenses already incurred by Sithe prior to the date of this Settlement for the
specific facilities and operation and maintenance prepayments identified in
Attachment D; and (ii) pursue the specific transmission losses claims raised by
Sithe in Docket No. EL95-38-000, subject to Sithe's reservation of rights set
forth in Section III, Paragraph 2, above. The provisions of this Paragraph 5
shall not hereafter be modified except as required by the Commission pursuant to
the public interest standard of Section 206 of the FPA.

      6. In addition to the foregoing, the Sponsoring Parties have agreed to
make certain modifications to the TSA and IA to: (i) implement this
Settlement; (ii) reflect the NYISO's operation and control of the New York
Control Area and to reflect the existence of the NYISO markets and its market
rules; and (iii) comply with the Commission's Order No. 614, 90 FERC
[Paragraph] 61,352 (2000). As noted in Paragraph 3 above, the amended and
restated TSA is included as Attachment A to the Settlement. The amended and
restated IA is included as Attachment B to the Settlement. Acceptance

                                       7
<Page>

or approval of this Settlement shall constitute acceptance or approval by the
Commission of these amendments to the TSA and the IA.

      7. The Sponsoring Parties shall retain any rights they may have to pursue
all issues related to: (a) the proposal of Niagara Mohawk and the other Member
Systems in Docket Nos. ER97-1523-011, ET AL., to impose marginal losses on
service under the TSA and the pursuit of the transmission losses issues and
requests for relief related thereto raised by Sithe in that proceeding; and (b)
all claims with respect to service rendered under the TSA after December 31,
2005.

      8. If the FERC does not accept this Settlement in its entirety or orders
changes to this Settlement that are unacceptable to either of the Sponsoring
Parties, then: (a) this Settlement shall terminate, be null and void and shall
have no binding effect under applicable law; (b) Sithe shall return the payments
discussed in Section III, Paragraphs 2 and 4 of this Settlement to Niagara
Mohawk within five (5) business days of the date of any such final Commission
order, with interest calculated in accordance with the interest rate set forth
in the Commission's regulations (calculated from the date that Sithe received
the payments to the date that Sithe returned the payments to Niagara Mohawk);
and (c) the Sponsoring Parties shall use good faith efforts to reach a mutually
agreeable settlement with the same economic impact and legal effect on the
Sponsoring Parties as this Settlement.

      SECTION IV. OTHER PROVISIONS

      1. The Sponsoring Parties agree to take all reasonable action to support
this Settlement and its implementation before the Commission.

                                       8
<Page>

      2. The Sponsoring Parties have both participated in the drafting of this
Settlement and, therefore, no rule of construction should apply that would
interpret this document more favorably to either Sponsoring Party.

      3. The rights conferred and obligations imposed on either Sponsoring Party
by this Settlement shall inure to the benefit of or be binding on that Party's
successors in interest or assignees as if each such successor or assignee was
itself a Sponsoring Party.

      4. This Settlement is made upon the express understanding that it
constitutes a negotiated settlement and no person or Sponsoring Party shall be
deemed to have approved, accepted, agreed to or otherwise consented to any
ratemaking or tariff principle or methodology underlying or supposed to underlie
any of the provisions herein. This Settlement shall not be deemed to have
established a "settled practice," as that term is used in PUBLIC SERVICE COMM'N
OF NEW YORK V. FERC, 642 F.2d 1335 (D.C. Cir. 1980), CERT. DENIED, 454 U.S. 879
(1981). The making of this Settlement shall not be deemed in any respect to
constitute an admission by either Sponsoring Party with respect to any
allegation or contention in this proceeding.

      5. The discussions that have produced this Settlement have been
conducted on the explicit understanding, pursuant to Rule 602(e) of the
Commission's Rules of Practice and Procedure, 18 C.F.R. Section 602(e)
(2000), that neither this Settlement, the accompanying Explanatory Statement,
nor any comment on this Settlement, are admissible in evidence against any
participant, except in any proceeding to enforce the provisions of the
Settlement, and on the further explicit understanding that any discussions
among the Sponsoring Parties with respect to this Settlement prior to the
execution and filing thereof shall not be subject to discovery or admissible
in evidence;

                                       9
<Page>

provided however that, notwithstanding the foregoing, the provisions of Section
III, Paragraph 4 of this Settlement shall be admissible in evidence and binding
on the Sponsoring Parties in any future proceedings in which Niagara Mohawk's
transmission rates or the Transmission Service Charge for withdrawals to serve
load in Niagara Mohawk's Transmission District (as those terms are defined in
the NYISO OATT) or other similar charges for the recovery of Niagara Mohawk's
transmission revenue requirements are at issue ("Transmission Rate Proceeding"),
as long as Niagara Mohawk is not seeking to assign such charges directly to
Sithe in the Transmission Rate Proceeding. At Niagara Mohawk's reasonable
request, Sithe shall provide supporting evidence in the form of testimony or
affidavit(s) in such a Transmission Rate Proceeding.

      6. This Settlement constitutes a full settlement with respect to Docket
Nos. EL99-65-000 and EL95-38-000, and supersedes any and all prior or
contemporaneous representations, agreements, instruments and understandings
between the participants, whether written or oral, relating to the matters
addressed herein. There are no other oral understandings, terms or conditions of
this Settlement, and none of the participants has relied upon any such
representation, express or implied in making this Settlement.

      7. The Commission is hereby requested to grant such waivers of its
regulations as may be necessary to effectuate all of the provisions of this
Settlement.

      8. Any number of counterparts of this Settlement may be executed, and each
shall have the same force and effect as an original instrument, as if each of
the Sponsoring Parties to all the counterparts had signed the same instrument.

                                       10
<Page>

         The undersigned party to this proceeding, by its signature, supports
this Settlement Agreement.

                                          NIAGARA MOHAWK POWER CORPORATION

                                          By: /s/ Edward J. Dienst
                                             -----------------------------------

Dated:  June 28, 2001

                                       11
<Page>

         The undersigned party to this proceeding, by its signature, supports
this Settlement Agreement.

                               SITHE/INDEPENDENCE POWER PARTNERS, L.P.
                               By: Sithe/Independence, Inc., its General Partner

                               By: /s/ Martin B. Rosenberg
                                  ----------------------------------------------

Dated:  June 28, 2001

                                       12
<Page>

                                  ATTACHMENT C

PURCHASED FACILITIES PAYMENT

         The Purchased Facilities Payment of $28,112,917.00 shall be in exchange
for the facilities that consist of the 345 kV Transmission Circuit from the
Independence Substation to the Clay Substation (Line #26). The facilities and
costs related to the facilities listed on Attachment D are excluded from the
Purchased Facilities Payment.

                                       13
<Page>

                                  ATTACHMENT D

                  The following facilities are excluded from the Purchased
Facilities Payment:

1.    Independence 345 kV Substation;

2.    Independence Plant Power System Stabilizer;

3.    Operation and Maintenance Pre-Payment to Niagara;

4.    Sithe's capitalized interest during construction;

5.    Niagara System Improvements for Adding Scriba to Clay 345 kV Circuit;

6.    The 345 kV Transmission Circuit from the Scriba Substation to the
      Independence Substation (Line #25); and

7.    Interest on Items 1-6 above.

                                       14

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