**Exhibit4.12**

**SECONDSUPPLEMENTAL INDENTURE ADDITIONAL SUBSIDIARY GUARANTEES**

SECOND SUPPLEMENTAL INDENTURE(this “*Supplemental Indenture*”),dated as of September 21, 2006, among Reliant Energy Power Supply,LLC (the “*Guaranteeing Subsidiary*”),a subsidiary of Reliant Energy, Inc. (or its permitted successor), a Delawarecorporation (the “*Company*”), theCompany, the other Guarantors (as defined in the Indenture referred to herein)and Wilmington Trust Company, as trustee under the indenture referred to below(the “*Trustee*”).

**WITNESSETH**

WHEREAS, the Company has heretofore executed anddelivered to the Trustee an indenture (the “*Indenture*”),dated as of July 1, 2003 providing for the original issuance of an aggregateprincipal amount of $550,000,000 of 9.50% Senior Secured Notes due 2013 (the “*Initial Note*s”), and, subject to the termsof the Indenture, future unlimited issuances of 9.50% Senior Secured Notes due2013 (the “*Additional Notes*,” andtogether with the Initial Notes, the “*Notes*”);

WHEREAS, the Indenture provides that under certaincircumstances the Guaranteeing Subsidiary shall execute and deliver to theTrustee a supplemental indenture pursuant to which the Guaranteeing Subsidiaryshall unconditionally guarantee all of the Company’s Obligations under theNotes and the Indenture (the “*Note Guarantee*”);and

WHEREAS, pursuant to Section 9.01 of the Indenture,the Trustee, the Company and the other Guarantors are authorized to execute anddeliver this Supplemental Indenture.

NOW THEREFORE, in consideration of the foregoing andfor good and valuable consideration, the receipt of which is herebyacknowledged, the Guaranteeing Subsidiary, the Trustee, the Company and theother Guarantors mutually covenant and agree for the equal and ratable benefitof the Holders of the Notes as follows:

1.             *Capitalized Terms*.  Unless otherwise defined in this SupplementalIndenture, capitalized terms used herein without definition shall have themeanings assigned to them in the Indenture.

2.             *Agreement to be Bound;Guarantee*.  The GuaranteeingSubsidiary hereby becomes a party to the Indenture as a Guarantor and as suchwill have all of the rights and be subject to all of the Obligations andagreements of a Guarantor under the Indenture. The Guaranteeing Subsidiary hereby agrees to be bound by all of theprovisions of the Indenture applicable to a Guarantor and to perform all of theObligations and agreements of a Guarantor under the Indenture.  In furtherance of the foregoing, the GuaranteeingSubsidiary shall be deemed a Guarantor for purposes of Article 12 of theIndenture, including, without limitation, Section 12.02 thereof.

3.             ***NEW YORK LAW TO GOVERN*. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TOCONSTRUE THIS SUPPLEMENTAL INDENTURE BUT WITHOUT GIVING EFFECT TO APPLICABLE**

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**PRINCIPLESOF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHERJURISDICTION WOULD BE REQUIRED THEREBY.**

4.             *Counterparts*.  The parties may sign any number of copies ofthis Supplemental Indenture.  Each signedcopy shall be an original, but all of them together represent the sameagreement.

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

6.             *The Trustee*.  The Trustee shall not be responsible in anymanner whatsoever for or in respect of the validity or sufficiency of thisSupplemental Indenture or for or in respect of the recitals contained herein,all of which recitals are made solely by the Guaranteeing Subsidiary and theCompany.

7.             *Ratification of Indenture;Supplemental Indenture  Part of Indenture*.  Except as expressly amended hereby, theIndenture 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 shall form a partof the Indenture for all purposes, and every Holder of Notes heretofore orhereafter authenticated and delivered shall by bound hereby.

 

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IN WITNESS WHEREOF, the parties hereto have causedthis Supplemental Indenture to be duly executed and attested, all as of thedate first above written.

Dated : September 21, 2006.
|   | RELIANT ENERGY POWER SUPPLY, LLC |
|--------|----------------------------------|
|   |                             |   |
|   | By:                              | /s/ Lloyd A. Whittington |
|   | Name:                            | Lloyd A. Whittington |
|   | Title:                           | Vice President and Treasurer |
|   |                             |   |
|   | RELIANT ENERGY, INC.             |
|   |                             |   |
|   | By:                              | /s/ Andrew C. Johannesen |
|   | Name:                            | Andrew C. Johannesen |
|   | Title:                           | Vice President and Asst. Treasurer |

 

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|        | RELIANT ENERGY ASSET  MANAGEMENT, LLC      |
|--------|--------------------------------------------|
|   | RELIANT ENERGY BROADBAND,  INC.            |
|   | RELIANT ENERGY CALIFORNIA  HOLDINGS, LLC   |
|   | RELIANT ENERGY  COMMUNICATIONS, INC.       |
|   | RELIANT ENERGY COOLWATER,  INC.            |
|   | RELIANT ENERGY CORPORATE  SERVICES, LLC    |
|   | RELIANT ENERGY ELLWOOD,  INC.              |
|   | RELIANT ENERGY ETIWANDA,  INC.             |
|   | RELIANT ENERGY FLORIDA,  LLC               |
|   | RELIANT ENERGY KEY/CON  FUELS, LLC         |
|   | RELIANT ENERGY MANDALAY,  INC.             |
|   | RELIANT ENERGY NORTHEAST  GENERATION, INC. |
|   | RELIANT ENERGY NORTHEAST  HOLDINGS, INC.   |
|   | RELIANT ENERGY ORMOND  BEACH, INC.         |
|   | RELIANT ENERGY POWER  GENERATION, INC.     |
|   | RELIANT ENERGY RETAIL  HOLDINGS, LLC       |
|   | RELIANT ENERGY SABINE  (TEXAS), INC.       |
|   | RELIANT ENERGY SERVICES  DESERT BASIN, LLC |
|   | RELIANT ENERGY SERVICES  MID-STREAM, LLC   |
|   | RELIANT ENERGY SEWARD, LLC                 |
|   | RELIANT ENERGY TRADING  EXCHANGE, INC.     |
|   | RELIANT ENERGY VENTURES,  INC.             |
|   | RELIANT ENERGY WHOLESALE GENERATION,  LLC  |
|   |                                       |   |
|        | By:                                        | /s/ Andrew C. Johannesen |
|   | Name:                                      | Andrew C. Johannesen |
|   | Title:                                     | Assistant Treasurer of the corporations and limited  liability companies, and of the general partners of the limited partnerships,  listed above |

 

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|   | RELIANT ENERGY  SERVICES, INC.          |
|--------|-----------------------------------------|
|   |                                    |   |
|   | By:                                     | /s/ Andrew C. Johannesen |
|   | Name:                                   | Andrew C. Johannesen |
|   | Title:                                  | Vice President and Treasurer |
|   |                                    |   |
|   | RELIANT ENERGY RETAIL  SERVICES, LLC    |
|   | RELIANT ENERGY ELECTRIC  SOLUTIONS, LLC |
|   | RELIANT ENERGY SOLUTIONS  EAST, LLC     |
|   |                                    |   |
|   | By:                                     | /s/ Lloyd A. Whittington |
|   | Name:                                   | Lloyd A. Whittington |
|   | Title:                                  | Vice President and Treasurer of the limited  liability companies listed above |

 

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|        | RELIANT ENERGY CAPTRADES  HOLDING CORP. |
|--------|-----------------------------------------|
|   | RELIANT ENERGY SABINE  (DELAWARE), INC. |
|   |                                    |   |
|        | By:                                     | /s/ Patricia F. Genzel |
|   | Name:                                   | Patricia F. Genzel |
|   | Title:                                  | President |

 

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|        | WILMINGTON TRUST COMPANY,  as Trustee |
|--------|---------------------------------------|
|   |                                  |   |
|        | By:                                   | /s/ Michael G. Oller |
|   | Authorized Signatory                  |

 

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