FORTY-FIRST SUPPLEMENTAL INDENTURE FOR ADDITIONAL SUBSIDIARY GUARANTEES

Exhibit 4.5

FORTY-FIRST SUPPLEMENTAL INDENTURE FOR
ADDITIONAL SUBSIDIARY GUARANTEES

FORTY-FIRST SUPPLEMENTAL INDENTURE (this “Supplemental Indenture for Additional Guarantees”), dated as of December 15, 2010, among Cottonwood Development LLC, Cottonwood Generating Partners II LLC, Cottonwood Generating Partners I LLC, Cottonwood Generating Partners III LLC, Cottonwood Energy Company LP, Cottonwood Technology Partners LP and Green Mountain Energy Company (each a “Guaranteeing Subsidiary” and together the “Guaranteeing Subsidiaries”), each an indirect subsidiary of NRG Energy, Inc., a Delaware corporation (the “Company”), the Company, the Existing Guarantors set forth on the signature page hereto (the “Existing Guarantors”) and Law Debenture Trust Company of New York, as trustee under the indentures referred to below (the “Trustee”).

W I T N E S S E T H

WHEREAS, the Company has heretofore executed and delivered to the Trustee an indenture (the “Base Indenture”), dated as of February 2, 2006, between the Company and the Trustee, as amended by a Thirty-Sixth Supplemental Indenture (the “Thirty-Sixth Supplemental Indenture” and, together with the Base Indenture, the “Indenture”), dated as of August 20, 2010, among the Company, the Guarantors named therein and the Trustee, providing for the original issuance of an aggregate principal amount of $1,100 million of 8.25% Senior Notes due 2020 (the “Initial Notes”), and, subject to the terms of the Thirty-Sixth Supplemental Indenture, future unlimited issuances of 8.25% Senior Notes due 2020 (the “Additional Notes,” and together with the Initial Notes, the “Notes”);

WHEREAS, the Indenture provides that under certain circumstances the Guaranteeing Subsidiaries shall execute and deliver to the Trustee a supplemental indenture pursuant to which the Guaranteeing Subsidiaries shall unconditionally guarantee all of the Company’s Obligations under the Notes and the Indenture (the “Additional Guarantees”); and

WHEREAS, pursuant to Section 4.17 of the Thirty-Sixth Supplemental Indenture, the Trustee, the Company and the Existing Guarantors are authorized and required to execute and deliver this Supplemental Indenture for Additional Guarantees.

NOW THEREFORE, in consideration of the foregoing and for good and valuable consideration, the receipt of which is hereby acknowledged, the Guaranteeing Subsidiaries, the Trustee, the Company and the Existing Guarantors mutually covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

1.             Capitalized Terms.  Unless otherwise defined in this Supplemental Indenture for Additional Guarantees, capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture.

2.             Agreement to be Bound; Guarantee.  The Guaranteeing Subsidiaries hereby become parties to the Supplemental Indenture as Guarantors and as such will have all of the rights and be subject to all of the Obligations and agreements of a Guarantor under the Indenture.  The Guaranteeing Subsidiaries hereby agree to be bound by all of the provisions of the Supplemental Indenture applicable to a Guarantor and to perform all of the Obligations and agreements of a Guarantor under the Supplemental Indenture.  In furtherance of the foregoing, the Guaranteeing Subsidiaries shall be deemed Guarantors for purposes of Article 10 of the Supplemental Indenture, including, without limitation, Section 10.02 thereof.

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3.             NEW YORK LAW TO GOVERN.  THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE FOR ADDITIONAL GUARANTEES BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

4.             Counterparts.  The parties may sign any number of copies of this Supplemental Indenture for Additional Guarantees.  Each signed copy shall be an original, but all of them together represent the same agreement.

5.             Effect of Headings.  The Section headings herein are for convenience only and shall not affect the construction hereof.

6.             The Trustee.  The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture for Additional Guarantees or for or in respect of the recitals contained herein, all of which recitals are made solely by the Guaranteeing Subsidiaries and the Company.

7.             Ratification of Indenture; Supplemental Indenture for Additional Guarantees Part of Indenture.  Except as expressly amended hereby, the Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect.  This Supplemental Indenture for Additional Guarantees shall form a part of the Indenture for all purposes, and every Holder of Notes heretofore or hereafter authenticated and delivered shall by bound hereby.

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture for Additional Guarantees to be duly executed and attested, all as of the date first above written.

Signature Page to Forty-First Supplemental Indenture

Signature Page to Forty-First Supplemental Indenture

Signature Page to Forty-First Supplemental Indenture

Signature Page to Forty-First Supplemental Indenture

Signature Page to Forty-First Supplemental Indenture

Signature Page to Forty-First Supplemental Indenture