EX-4.1






SIXTEENTH SUPPLEMENTAL INDENTURE FOR

ADDITIONAL SUBSIDIARY GUARANTEES




Sixteenth Supplemental Indenture (this “Supplemental Indenture for Additional
Guarantees”), dated as of April 28, 2009, among NRG Texas Holding Inc.(the “Guaranteeing
Subsidiary”), 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 first supplemental indenture (the “First Supplemental Indenture”), dated as of February 2, 2006,
among the Company, the Guarantors named therein and the Trustee, providing for the original
issuance of an aggregate principal amount of $1,200 million of 7.250% Senior Notes due 2014 (the
“Initial Notes”), and, subject to the terms of the Indenture, future unlimited issuances of 7.250%
Senior Notes due 2014 (the “Additional Notes,” and together with the Initial Notes, the “Notes”), a
third supplemental indenture (the “Third Supplemental Indenture”), dated as of March 14, 2006,
among the Company, the Existing Guarantors party thereto and the Trustee, a fifth supplemental
indenture (the “Fifth Supplemental Indenture”), dated as of April 28, 2006, among the Company, the
Existing Guarantors party thereto and the Trustee, a seventh supplemental indenture (the “Seventh
Supplemental Indenture"), dated as of November 13, 2006, among the Company, the Existing Guarantors
and the Trustee, a tenth supplemental indenture, dated July 19, 2007, among the Company, the
Existing Guarantors party thereto and the Trustee (the “Tenth Supplemental Indenture") and a
thirteenth supplemental indenture, dated as of August 28, 2007, among the Company, the Existing
Guarantors and the Trustee (together with the Base Indenture, the First Supplemental Indenture, the
Third Supplemental Indenture, the Fifth Supplemental Indenture, the Seventh Supplemental Indenture,
the Tenth Supplemental Indenture and the Thirteenth Supplemental Indenture, the “Indenture”);



WHEREAS, the Indenture provides that under certain circumstances the Guaranteeing Subsidiary
shall execute and deliver to the Trustee a supplemental indenture pursuant to which the
Guaranteeing Subsidiary 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 First Supplemental Indenture, the Trustee, the
Company and the other 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 Subsidiary, the Trustee, the Company and
the other 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 Subsidiary hereby becomes party to the
First Supplemental 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. The Guaranteeing
Subsidiary hereby agrees to be bound by all of the provisions of the First Supplemental Indenture
applicable to a Guarantor and to perform all of the Obligations and agreements of a Guarantor under
the First Supplemental Indenture. In furtherance of the foregoing, The Guaranteeing Subsidiary
shall be deemed a Guarantor for purposes of Article 10 of the First 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 Subsidiary 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.



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.



Guaranteeing Subsidiary:



NRG TEXAS HOLDING INC.



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Vice President & Treasurer





Issuer:



NRG ENERGY, INC.



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Vice President & Treasurer





Existing Guarantors:

ARTHUR KILL POWER LLC

ASTORIA GAS TURBINE POWER LLC

BERRIANS I GAS TURBINE POWER LLC

BIG CAJUN II UNIT 4 LLC

CABRILLO POWER I LLC

CABRILLO POWER II LLC

CHICKAHOMINY RIVER ENERGY CORP.

COMMONWEALTH ATLANTIC POWER LLC

CONEMAUGH POWER LLC

CONNECTICUT JET POWER LLC

DEVON POWER LLC

DUNKIRK POWER LLC

EASTERN SIERRA ENERGY COMPANY

EL SEGUNDO POWER LLC

EL SEGUNDO POWER II LLC

HANOVER ENERGY COMPANY

HOFFMAN SUMMIT WIND PROJECT, LLC

HUNTLEY IGCC LLC

HUNTLEY POWER LLC

INDIAN RIVER IGCC LLC

INDIAN RIVER OPERATIONS INC.

INDIAN RIVER POWER LLC

JAMES RIVER POWER LLC

KAUFMAN COGEN LP

KEYSTONE POWER LLC

LAKE ERIE PROPERTIES INC.

LOUISIANA GENERATING LLC

MIDDLETOWN POWER LLC

MONTVILLE IGCC LLC

MONTVILLE POWER LLC

NEO CHESTER-GEN LLC

NEO CORPORATION

NEO FREEHOLD-GEN LLC

NEO POWER SERVICES INC.

NEW GENCO GP, LLC

NORWALK POWER LLC

NRG AFFILIATE SERVICES INC.

NRG ARTHUR KILL OPERATIONS INC.

NRG ASIA-PACIFIC, LTD.

NRG ASTORIA GAS TURBINE OPERATIONS, INC.

NRG BAYOU COVE LLC

NRG CABRILLO POWER OPERATIONS INC.

NRG CADILLAC OPERATIONS INC.

NRG CALIFORNIA PEAKER OPERATIONS LLC

NRG CEDAR BAYOU DEVELOPMENT COMPANY, LLC

NRG CONNECTICUT AFFILIATE SERVICES INC.

NRG DEVON OPERATIONS INC.

NRG DUNKIRK OPERATIONS INC.

NRG EL SEGUNDO OPERATIONS INC.

NRG GENERATION HOLDINGS, INC.

NRG HUNTLEY OPERATIONS INC.

NRG INTERNATIONAL LLC

NRG KAUFMAN LLC

NRG MESQUITE LLC

NRG MIDATLANTIC AFFILIATE SERVICES INC.

NRG MIDDLETOWN OPERATIONS INC.

NRG MONTVILLE OPERATIONS INC.

NRG NEW JERSEY ENERGY SALES LLC

NRG NEW ROADS HOLDINGS LLC

NRG NORTH CENTRAL OPERATIONS INC.

NRG NORTHEAST AFFILIATE SERVICES INC.

NRG NORWALK HARBOR OPERATIONS INC.

NRG OPERATING SERVICES, INC.

NRG OSWEGO HARBOR POWER OPERATIONS INC.

NRG POWER MARKETING LLC

NRG ROCKY ROAD LLC

NRG SAGUARO OPERATIONS INC.

NRG SOUTH CENTRAL AFFILIATE SERVICES INC.

NRG SOUTH CENTRAL GENERATING LLC

NRG SOUTH CENTRAL OPERATIONS INC.

NRG TEXAS LLC

NRG TEXAS POWER LLC

NRG WEST COAST LLC

NRG WESTERN AFFILIATE SERVICES INC.

OSWEGO HARBOR POWER LLC

PADOMA WIND POWER, LLC

SAGUARO POWER LLC

SAN JUAN MESA WIND PROJECT II, LLC

SOMERSET OPERATIONS INC.

SOMERSET POWER LLC

TEXAS GENCO FINANCING CORP.

TEXAS GENCO GP, LLC

TEXAS GENCO HOLDINGS, INC.

TEXAS GENCO OPERATING SERVICES, LLC

VIENNA OPERATIONS INC.

VIENNA POWER LLC

WCP (GENERATION) HOLDINGS LLC

WEST COAST POWER LLC



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Treasurer





GCP FUNDING COMPANY, LLC




TEXAS GENCO LP, LLC



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Manager





NRG SOUTH TEXAS LP



By: Texas Genco GP, LLC, its General Partner



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Vice President & Treasurer




TEXAS GENCO SERVICES, LP



By: New Genco GP, LLC, its General Partner



By: /s/ Christopher S. Sotos

Name: Christopher S. Sotos

Title: Vice President & Treasurer







NRG CONSTRUCTION LLC



By: /s/ Rachel Smith

Name: Rachel Smith

Title: Treasurer







Attest:



	 	 	 
	By: /s/ Tanuja M. Dehne

	Name:

Title:

	 	Tanuja M. Dehne

Corporate Secretary






LAW DEBENTURE TRUST COMPANY OF NEW YORK,



as Trustee



	 	 	 
	By: /s/ James D. Heaney

	Name:

Title:

	 	James D. Heaney

Managing Director