**Exhibit 4.8**

**SECONDSUPPLEMENTAL INDENTUREADDITIONAL 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 9.25% Senior Secured Notes due 2010 (the “*Initial Notes*”), and, subject to the termsof the Indenture, future unlimited issuances of 9.25% Senior Secured Notes due2010 (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 Subsidiaryhereby agrees to be bound by all of the provisions of the Indenture applicableto a Guarantor and to perform all of the Obligations and agreements of aGuarantor under the Indenture. In furtherance of the foregoing, theGuaranteeing Subsidiary shall be deemed a Guarantor for purposes of Article 12of the Indenture, 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 APPLICABLEPRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWSOF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.**

4.             *Counterparts*.  The parties may sign any number of copies ofthis Supplemental Indenture. Each signed copy shall be an original, but all ofthem together represent the same agreement.

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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. ThisSupplemental Indenture shall form a part of the Indenture for all purposes, andevery Holder of Notes heretofore or hereafter authenticated and delivered shallby bound hereby.

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IN WITNESS WHEREOF, theparties hereto have caused this Supplemental Indenture to be duly executed andattested, all as of the date 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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