Exhibit 10.15

Reimbursement Agreement(this "Agreement"), dated as of October 26, 2001, entered
into between Edison Mission Energy, a Delaware corporation ("EME"), and Midwest Generation, LLC, a Delaware limited liability company
("Midwest").

WHEREAS,
Midwest is a wholly owned subsidiary of Edison Mission Midwest Holdings Co. ("Holdings"), and is subject to the certain covenants
set forth in (A) the Credit Agreement, dated as of December 15, 1999 (as amended, modified or supplemented and in effect from time to time and together with any refinancing or
replacement thereof, the "Holdings Credit Agreement"), among Holdings and certain commercial lending institutions party thereto (the
"Lenders") and The Chase Manhattan Bank, as the Administrative Agent; (B) the Participation Agreement, dated as of December 15, 1999 (as
heretofore amended, modified and supplemented, the "Participation Agreement (T1)") among Collins Holdings EME, LLC ("Collins
Holdings"), Wilmington Trust Company, as the Owner Trustee, Collins Trust I, as the Owner Lessor, Collins Generation I, LLC, as Owner Participant, Holdings, Midwest, Funding
LLC, Bayerische Landesbank International S.A. (the "Midwest LC Issuer"), Bayerische Landesbank Girozentrale ("RCE LC
Issuer") and the Holder Representative (as such term is defined therein); (C) the Participation Agreement, dated as of December 15, 1999 (as heretofore amended,
modified and supplemented, the "Participation Agreement (T2)") among Collins Holdings, Wilmington Trust Company, as the Owner Trustee, Collins Trust II,
as the Owner Lessor, Collins Generation II, LLC, as Owner Participant, Holdings, Midwest, Funding LLC, the Midwest LC Issuer, the RCE LC Issuer and the Holder Representative (as such term is defined
therein); (D) the Participation Agreement, dated as of December 15, 1999 (as heretofore amended, modified and supplemented, the "Participation Agreement
(T3)") among Collins Holdings, Wilmington Trust Company, as the Owner Trustee, Collins Trust III, as the Owner Lessor, Collins Generation III, LLC, as Owner Participant,
Holdings, Midwest, Funding LLC, the Midwest LC Issuer, the RCE LC Issuer and the Holder Representative (as such term is defined therein); (E) the Participation Agreement, dated as of
December 15, 1999 (as heretofore amended, modified and supplemented, the "Participation Agreement (T4)", together with Participation Agreement
(T1), Participation Agreement (T2) and Participation Agreement (T3), "Collins Participation Agreements") among Collins Holdings, Wilmington Trust
Company, as the Owner Trustee, Collins Trust IV, as the Owner Lessor, Collins Generation IV, LLC, as Owner Participant, Holdings, Midwest, Funding LLC, the Midwest LC Issuer, the RCE LC Issuer and the
Holder Representative (as such term is defined therein); and (F) the Credit Agreement, dated as of May 9, 2000 (as amended, modified or supplemented and in effect from time to time, the
"CAPEX Credit Agreement", together with the Holdings Credit Agreement and Collins Participation Agreements (and related Operative Documents defined
therein), the "Holdings Credit Facilities") among Holdings, Societe Generale and Bayerische Landesbank Girozentrale ("Capex
Lenders", and together with the Lenders and Lease Financing Parties under the Collins Participation Agreements, the "Creditor
Parties");

WHEREAS,
Midwest has also entered into a transaction pursuant to the Participation Agreements (as defined below) whereby Midwest sold certain of its generating assets to Powerton Trust
I, Powerton Trust II, Joliet Trust I and Joliet Trust II (the "Owner Lessors") and the Owner Lessors leased such generating assets to Midwest;

WHEREAS,
Midwest loaned to Edison Mission Energy, a California corporation and predecessor to EME ("EME California"), the proceeds of the sale of the generating assets to the Owner
Lessor (the "Intercompany Loan");

WHEREAS,
in connection with the transactions contemplated by the Participation Agreements (as defined below), Holdings and Midwest requested the Creditor Parties to approve, and the
Credit Parties have approved, such sale and lease-back of generating assets;

WHEREAS,
in consideration for the Creditor Parties' approval of the transactions contemplated by the Participation Agreements and the Intercompany Loan, EME California and Midwest
entered

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into
a Reimbursement Agreement, dated as of August 17, 2000 (the "Original Reimbursement Agreement"); and

WHEREAS,
pursuant to that certain Agreement and Plan of Merger, dated October 11, 2001, by and between EME California and EME, EME California merged with and into EME (the
"Merger"), with EME being the surviving corporation of the Merger; and

WHEREAS,
this Agreement is being executed and delivered by the parties to evidence the succession of EME to EME California and the assumption by EME of the covenants, agreements, and
obligations of EME California under the Operative Documents; and

WHEREAS,
all things necessary to make this Agreement a valid agreement according to its terms have been done.

NOW,
THEREFORE, for and in consideration for the Creditor Parties' approval of the transactions contemplated by the Participation Agreements (as defined below) and the Intercompany Loan,
and mutual covenants herein contained, and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the parties hereto, intending to be legally bound, do
hereby covenant and agree as follows:

1.Definitions.Unless otherwise expressly provided herein, capitalized terms used in this Agreement but not
defined herein shall have meanings given to such terms in Appendix A to each of the Participation Agreements. The following terms, when used herein, shall have the following meanings:

"Combined Rent" means, collectively, Powerton Rent (T1), Powerton Rent (T2), Joliet Rent (T1) and Joliet Rent (T2).

"Joliet Lease Intercompany Note (T1)" means the EME Note (as defined in the Joliet Lease Participation Agreement (T1)) dated the Closing
Date (as defined in the Joliet Lease Participation Agreement (T1)) evidencing the loan by Midwest to EME of the proceeds of the Joliet Lease Transaction (T1).

"Joliet Lease Intercompany Note (T2)" means the EME Note (as defined in the Joliet Lease Participation Agreement (T2)) dated the Closing
Date (as defined in the Joliet Lease Participation Agreement (T2)) evidencing the loan by Midwest to EME of the proceeds of the Joliet Lease Transaction (T2).

"Joliet Lease Intercompany Notes" means, collectively, the Joliet Lease Intercompany Note (T1) and the Joliet Intercompany Note (T2).

"Joliet Lease Operative Documents" means, collectively, the Joliet Lease Operative Documents (T1) and the Joliet Lease Operative Documents
(T2).

"Joliet Lease Operative Documents (T1)" means, collectively, the Operative Documents as defined in the Joliet Lease Participation
Agreement (T1).

"Joliet Lease Operative Documents (T2)" means, collectively, the Operative Documents as defined in the Joliet Lease Participation
Agreement (T2).

"Joliet Lease Participation Agreement (T1)" means the Participation Agreement (T1) dated as of August 17, 2000 by and among
Midwest, EME, Joliet Trust I, Wilmington Trust Company, Joliet Generation I, the Lease Indenture Trustee named therein and the Pass Through Trustees named therein.

"Joliet Lease Participation Agreement (T2)" means the Participation Agreement (T2) dated as of August 17, 2000 by and among
Midwest, EME, Joliet Trust II, Wilmington Trust Company, Joliet

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Generation
II, the Lease Indenture Trustee named therein and the Pass Through Trustees named therein.

"Joliet Lease Participation Agreements" means, collectively, the Joliet Lease Participation Agreement (T1) and the Joliet Lease
Participation Agreement (T2).

"Joliet Rent (T1)" means Rent as defined in the Joliet Lease Participation Agreement (T1).

"Joliet Rent (T2)" means Rent as defined in the Joliet Lease Participation Agreement (T2).

"Joliet Subordination Agreement (T1)" means the Subordination Agreement dated as of August 17, 2000 between Joliet Trust I, the
Owner Participant (as defined in the Joliet Participation Agreement (T1)), the Lease Indenture Trustee (as defined in the Joliet Participation Agreement (T1)) and the Holdings Collateral Agent.

"Joliet Subordination Agreement (T2)" means the Subordination Agreement dated as of August 17, 2000 between Joliet Trust II, the
Owner Participant (as defined in the Joliet Participation Agreement (T2)), the Lease Indenture Trustee (as defined in the Joliet Participation Agreement (T2)) and the Holdings Collateral Agent.

"Joliet Trust I" means Joliet Trust I, a Delaware business trust.

"Joliet Trust II" means Joliet Trust II, a Delaware business trust.

"Lease Financing Parties" shall mean, as the context shall require, all or any of the parties to Powerton/Joliet Lease Operative
Documents, including the Wilmington Trust Company and excluding ComEd and the Holdings Collateral Agent.

"Participation Agreements" means, collectively, the Powerton Lease Participation Agreements and the Joliet Lease Participation Agreements
(as amended, modified or supplemented and in effect from time to time).

"Powerton Lease Intercompany Note (T1)" means the EME Note (as defined in the Powerton Lease Participation Agreement (T1)) dated the
Closing Date (as defined in the Powerton Lease Participation Agreement (T1)) evidencing the loan by Midwest to EME of the proceeds of the Powerton Lease Transaction (T1).

"Powerton Lease Intercompany Note (T2)" means the EME Note (as defined in the Powerton Lease Participation Agreement (T2)) dated the
Closing Date (as defined in the Powerton Lease Participation Agreement (T2)) evidencing the loan by Midwest to EME of the proceeds of the Powerton Lease Transaction (T2).

"Powerton Lease Intercompany Notes" means, collectively, the Powerton Lease Intercompany Note (T1) and the Powerton Lease Intercompany
Note (T2).

"Powerton Lease Operative Documents" means, collectively, the Powerton Lease Operative Documents (T1) and the Powerton Lease Operative
Documents (T2).

"Powerton Lease Operative Documents (T1)" means, collectively, the Operative Documents as defined in the Powerton Lease Participation
Agreement (T1).

"Powerton Lease Operative Documents (T2)" means, collectively, the Operative Documents as defined in the Powerton Lease Participation
Agreement (T2).

"Powerton Lease Participation Agreement (T1)" means the Participation Agreement (T1) dated as of August 17, 2000 by and among
Midwest, EME, Powerton Trust I, Wilmington Trust Company, Powerton Generation I, the Lease Indenture Trustee named therein and the Pass Through Trustees named therein.

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"Powerton Lease Participation Agreement (T2)" means the Participation Agreement (T2) dated as of August 17, 2000 by and among
Midwest, EME, Powerton Trust II, Wilmington Trust Company, Powerton Generation II, the Lease Indenture Trustee named therein and the Pass Through Trustees named therein.

"Powerton Lease Participation Agreements" means, collectively, the Powerton Lease Participation Agreement (T1) and the Powerton Lease
Participation Agreement (T2).

"Powerton Rent (T1)" means Rent as defined in the Powerton Lease Participation Agreement (T1).

"Powerton Rent (T2)" means Rent as defined in the Powerton Lease Participation Agreement (T2).

"Powerton Subordination Agreement (T1)" means the Subordination Agreement dated as of August 17, 2000 between Powerton Trust I, the
Owner Participant (as defined in the Powerton Participation Agreement (T1)), the Lease Indenture Trustee (as defined in the Powerton Participation Agreement (T1)) and the Holdings Collateral Agent.

"Powerton Subordination Agreement (T2)" means the Subordination Agreement dated as of August 17, 2000 between Powerton Trust II,
the Owner Participant (as defined in the Powerton Participation Agreement (T2)), the Lease Indenture Trustee (as defined in the Powerton Participation Agreement (T2)) and the Holdings Collateral
Agent.

"Powerton Trust I" means Powerton Trust I, a Delaware business trust.

"Powerton Trust II" means Powerton Trust II, a Delaware business trust.

"Powerton/Joliet Lease Intercompany Notes" means, collectively, the Powerton Lease Intercompany Notes and the Joliet Lease Intercompany
Notes.

"Powerton/Joliet Lease Operative Documents" means, collectively, the Powerton Lease Operative Documents and the Joliet Lease Operative
Documents.

"Powerton/Joliet Lease Participation Agreements" means, collectively, the Powerton Lease Participation Agreement (T1), Powerton Lease
Participation Agreement (T2), Joliet Lease Participation Agreement (T1) and Joliet Lease Participation Agreement (T2).

"Powerton/Joliet Subordination Agreements" means, collectively, the Powerton Subordination Agreement (T1), the Powerton Subordination
Agreement (T2), the Joliet Subordination Agreement (T1) and the Joliet Subordination Agreement (T2).

2.Obligation to Reimburse Midwest.



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3.Obligation Absolute.EME's obligation under this Agreement shall be absolute and unconditional and shall not
be subject to any defense or be affected by any right of setoff, counterclaim or recoupment
which EME may now or hereafter have against Midwest or any other person for any reason whatsoever.

4.Notices.All notices, requests and other communications provided for herein (including, without limitation,
any modifications of, or waivers under, this Agreement) shall be given or made in writing (including, without limitation, by telecopy) delivered to the intended recipient at the "Address for Notices"
specified below its name on the signature pages hereof, or, as to any party, at such other address as shall be designated by such party in a notice to each other party. Except as otherwise provided in
this Agreement, all such communications shall be deemed to have been duly given (a) when received by certified mail or by an international courier, such as Federal Express, by such Person, at
said address of such Person or (b) when transmitted by facsimile to the number specified below and the receipt confirmed telephonically by recipient, providedthat such facsimile is promptly
followed by a copy of such notice delivered to such Person by postage-prepaid certified mail, or by an
international courier, such as Federal Express.

5.Waivers; Etc.The terms of this Agreement may be waived, altered or amended only by an instrument in writing
duly executed by EME and Midwest. Any such amendment or waiver shall be binding upon EME and Midwest.

6.Successors and Assigns.This Agreement shall be binding upon and inure to the benefit of the respective
successors and assigns of each of EME and Midwest.

7.Counterparts; Integration; Effectiveness.This Agreement may be executed in any number of counterparts, all
of which when taken together shall constitute one and the same instrument, and any of the parties hereto may execute this Agreement by signing any such counterpart. This Agreement constitutes the
entire agreement and understanding among the parties hereto and supersedes any and all prior agreements and understandings, written or oral, relating to the subject matter hereof.

8.Severability.If any provision hereof is invalid or unenforceable in any jurisdiction, then, to the fullest
extent permitted by applicable law, (a) the other provisions hereof shall remain in full force and effect in such jurisdiction and shall be liberally construed in order to carry out the
intentions of the parties hereto as nearly as may be possible and (b) the invalidity or unenforceability of any provision hereof in any jurisdiction shall not affect the validity or
enforceability of such provision in any other jurisdiction.

9.Headings.Headings appearing herein are used solely for convenience of reference and are not intended to
affect the interpretation of any provision of this Agreement.

10.WAIVER OF JURY TRIAL.EACH OF EME
AND MIDWEST HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL
BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

11.NO THIRD PARTY BENEFICIARIES.THE
AGREEMENTS OF THE PARTIES HERETO ARE SOLELY FOR THE BENEFIT OF MIDWEST (AND EACH PERSON WHO CLAIMS THROUGH MIDWEST), AND NO PERSON (OTHER THAN THE PARTIES HERETO AND THEIR SUCCESSORS AND ASSIGNS
PERMITTED HEREUNDER) SHALL HAVE ANY RIGHTS HEREUNDER.

12.Governing Law; Submission to Jurisdiction.This Agreement shall be governed by, and
construed in accordance with, the law of the State of New York. EME hereby submits to the non-exclusive jurisdiction of the United States District Court for the Southern District of New
York and of the Supreme Court of the State of New York sitting in New York County (including its

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Appellate
Division) and of any other appellate court in the State of New York for the purposes of all legal proceedings arising out of or relating to this Agreement or the transactions contemplated
hereby. EME hereby irrevocably waives, to the fullest extent permitted by applicable law, any objection that it may now or hereafter have to the laying of the venue of any such proceeding brought in
such a court and any claim that any such proceeding brought in such a court has been brought in an inconvenient forum.

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IN WITNESS WHEREOF,the parties have cause this Agreement to be duly executed and delivered as of the day and year above written.

| |  | EDISON MISSION ENERGY                                                                                        
| |  | -------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                          
| |  | Address for Notices:                                                                                         
| |  | 18101 Von Karman Avenue
Suite 1700
Irvine, CA 92616
Attention: General Counsel
Telecopier No.: (949) 752-1420

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| |  | MIDWEST GENERATION, LLC                                                                                                                          
| |  | -------------------------------------------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                                                              
| |  | Address for Notices:                                                                                                                             
| |  | One Financial Place
440 South LaSalle Street, Suite 3500
Chicago, Illinois 60605
Attn: President
Telecopier No.: (312) 583-6111                  
| |  | with a copy to:                                                                                                                                  
| |  | Edison Mission Midwest Holdings Co.
18101 Von Karman Avenue
Suite 1700
Irvine, CA 92616
Attention: General Counsel
Telecopier No.: (949) 752-1420

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