Exhibit 4.3

NINETY-EIGHTH SUPPLEMENTAL INDENTURE FOR
ADDITIONAL SUBSIDIARY GUARANTEES

NINETY-EIGHTH SUPPLEMENTAL INDENTURE (this “Supplemental Indenture for Additional Guarantees”), dated as of September 4, 2013, among Gregory Partners, LLC, a Delaware limited liability company, Gregory Power Partners LLC, a Delaware limited liability company, NRG Curtailment Solutions LLC, a Delaware limited liability company, Energy Curtailment Specialists, Inc., a New York corporation, Ace Energy, Inc., a New York corporation, and Bidurenergy, Inc., a New York corporation (each, a “Guaranteeing Subsidiary” and collectively, the “Guaranteeing Subsidiaries”), each a subsidiary of NRG Energy, Inc., a Delaware corporation (the “Company”), the Company, the Existing Guarantors set forth on the signature pages hereto (the “Existing Guarantors”) and Law Debenture Trust Company of New York, as trustee under the Indenture 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 forty-second supplemental indenture (the “Forty-Second Supplemental Indenture”), dated as of January 26, 2011, among the Company, the Guarantors party thereto and the Trustee, providing for the original issuance of an aggregate principal amount of $1,200 million of 7.625% Senior Notes due 2018 (the “Initial Notes”), and, subject to the terms of the Forty-Second Supplemental Indenture, future unlimited issuances of 7.625% Senior Notes due 2018 (the “Additional Notes,” and together with the Initial Notes, the “Notes”), as amended by a forty-ninth supplemental indenture, dated as of May 20, 2011, among the Company, the Guarantors party thereto and the Trustee (the “Forty-Ninth Supplemental Indenture”), a fifty-fifth supplemental indenture, dated as of November 8, 2011, among the Company, the Guarantors party thereto and the Trustee (the “Fifty-Fifth Supplemental Indenture”), a sixty-first supplemental indenture, dated as of April 5, 2012, among the Company, the Guarantors party thereto and the Trustee (the “Sixty-First Supplemental Indenture”), a sixty-seventh supplemental indenture, dated as of May 9, 2012, among the Company, the Guarantors party thereto and the Trustee (the “Sixty-Seventh Supplemental Indenture”), a seventy-third supplemental indenture, dated as of October 9, 2012, among the Company, the Guarantors party thereto and the Trustee (the “Seventy-Third Supplemental Indenture”), a seventy-ninth supplemental indenture, dated as of January 3, 2013, among the Company, the Guarantors party thereto and the Trustee (the “Seventy-Ninth Supplemental Indenture”), an eighty-fifth supplemental indenture, dated as of March 13, 2013, among the Company, the Guarantors party thereto and the Trustee (the “Eighty-Fifth Supplemental Indenture”), an eighty-ninth supplemental indenture, dated as of March 13, 2013, among the Company, the Guarantors party thereto and the Trustee (the “Eighty-Ninth Supplemental Indenture”), and a ninety-second supplemental indenture, dated as of May 2, 2013, among the Company, the Existing Guarantors and the Trustee (the “Ninety-Second Supplemental Indenture” and together with the Base Indenture, the Forty-Second Supplemental Indenture, the Forty-Ninth Supplemental Indenture, the Fifty-Fifth Supplemental Indenture, the Sixty-First Supplemental Indenture, the Sixty-Seventh Supplemental Indenture, the Seventy-Third Supplemental Indenture, the Seventy-Ninth Supplemental Indenture, the Eighty-Fifth Supplemental Indenture and the Eighty-Ninth Supplemental Indenture, the “Indenture”);

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 Forty-Second 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.  Each Guaranteeing Subsidiary hereby becomes party to the Indenture as a Guarantor 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.  Each Guaranteeing Subsidiary hereby agrees to be bound by all of the provisions of the Indenture applicable to a Guarantor and to perform all of the Obligations and agreements of a Guarantor under the Indenture.  In furtherance of the foregoing, each Guaranteeing Subsidiary shall be deemed a Guarantor for purposes of Article 10 of the Forty-Second Supplemental Indenture, including, without limitation, Section 10.02 thereof.

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.

[Signatures on following pages]

2

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 Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture

Signature Page to Ninety-Eighth Supplemental Indenture