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                                                                   Exhibit 10.27

                 THIRD AMENDMENT TO CREDIT AGREEMENT AND CONSENT

     This THIRD AMENDMENT TO CREDIT AGREEMENT AND CONSENT (this "Agreement") is
entered into as of October 1, 2007 in connection with (i) that certain Credit
Agreement, dated as of September 1, 2006, among SNOWFLAKE WHITE MOUNTAIN POWER,
LLC ("SWMP"), RENEGY, LLC ("Renegy"), RENEGY TRUCKING, LLC ("Renegy Trucking"
and together with Renegy and SWMP, the "Borrowers"), the financial institutions
from time to time party thereto (collectively, the "Lenders") and COBANK, ACB,
as administrative agent for the Lenders (in such capacity, the "Administrative
Agent"), as letter of credit issuer, collateral agent and as a Lender, as
amended (as further amended from time to time, the "Credit Agreement"), (ii)
that certain Pledge Agreement, dated as of September 1, 2006, among Stone Axe
Power Ranch, LLC, SWMP and COBANK, ACB (the "Stone Axe Pledge Agreement"), and
(iii) that certain Pledge Agreement, dated as of September 1, 2006, among New
Mexico and Arizona Land Company, LLC, Renegy, Renegy Trucking and COBANK, ACB
(the "NMALC Pledge Agreement"). Terms used herein but not defined shall have the
meaning given to them in the Credit Agreement and section references refer to
sections of the Credit Agreement unless otherwise stated.

     WHEREAS, the Borrowers have entered into that certain Contribution and
Merger Agreement, dated May 8, 2007, as amended (the "Merger Agreement"), by and
among the Borrowers, Catalytica Energy Systems, Inc., a Delaware corporation
("Catalytica"), Renegy Holdings, Inc. ("Renegy Holdings"), Snowflake Acquisition
Corporation, Robert M. Worsley, Christi M. Worsley and the Robert M. Worsley and
Christi M. Worsley Revocable Trust, pursuant to which the Borrowers and
Catalytica will combine their businesses and become wholly-owned subsidiaries of
Renegy Holdings (the "Transaction").

     WHEREAS, the Borrowers have requested that Administrative Agent and the
undersigned Lender(s) consent to the Transaction and the consummation of the
transactions contemplated thereby.

     WHEREAS, the Borrowers have requested that the Required Lenders agree to
amend the Credit Agreement in certain other respects as set forth herein.

     NOW THEREFORE, in consideration of the premises, and for other good and
valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto agree as follows:

     1. Consents. The Administrative Agent and undersigned Lender(s) hereby:

          (a) consent to the Transaction and the related transactions
     contemplated by the Merger Agreement;

          (b) consent to the amendments to the Borrowers' articles of
     organization in substantially the forms attached hereto as Exhibit A in
     connection with the Transaction;

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          (c) consent to the execution of the Pledge and Security Agreement
     among Renegy Holdings, SWMP, Renegy, Renegy Trucking and COBANK, ACB in
     substantially the form of Exhibit B hereto (the "Renegy Holdings Pledge
     Agreement");

          (d) consent to the termination of the Stone Axe Pledge Agreement and
     the NMALC Pledge Agreement, effective as of the closing of the Transaction;
     and

          (e) consent to the filing of appropriate UCC financing statements,
     including, without limitation, UCC-1 and UCC-3 statements, in connection
     with the execution of the Renegy Holdings Pledge Agreement and the
     termination of the Stone Axe Pledge Agreement and the NMALC Pledge
     Agreement, as contemplated above.

     2. Waivers. The Administrative Agent and undersigned Lender(s) hereby:

          (a) waive any Default or Event of Default under the Credit Agreement,
     including without limitation, Sections 5.4.11, 6.5, 6.8, 6.11 and 8.1.13
     thereto, or any defaults under the Collateral Documents, arising from any
     of the actions or matters set forth in Section 1 above; and

          (b) waive any Default or Event of Default under the Stone Axe Pledge
     Agreement and the NMALC Pledge Agreement, including without limitation,
     Sections 4.4, 4.5, 4.14, 5.3, 5.5 and 5.11 thereto, arising from any of the
     actions or matters set forth in Section 1 above.

     3. Amendments. The Credit Agreement is hereby amended as follows:

          (a) Exhibit A to the Credit Agreement is hereby amended to replace the
     definition of "Collateral Documents" with the following definition:

               "Collateral Documents" means the Mortgage, the Bond Pledge
          Agreement, the Renegy Holdings Pledge Agreement, the Security
          Agreement, each Consent, and any fixture filings, financing
          statements, or other similar documents filed, recorded or delivered in
          connection with the foregoing.

          (b) Exhibit A to the Credit Agreement is hereby amended to delete the
     following definitions in their entirety:

               "Pledge Agreement (NZ Land)"

               "Pledge Agreement (Stone Axe)"

          (c) Exhibit A to the Credit Agreement is hereby amended to add the
     following definition:

               "Renegy Holdings Pledge Agreement" means that certain Pledge
          Agreement among Borrowers and Collateral Agent, dated as of October 1,
          2007.


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          (d) For the avoidance of doubt, as of the date hereof, any reference
     in the Credit Documents to "Pledge Agreement (NZ Land)" or "Pledge
     Agreement (Stone Axe)" shall mean the Renegy Holdings Pledge Agreement, and
     any reference to Exhibit D-3-A shall refer to the Renegy Holdings Pledge
     Agreement.

     4. Conditions. The consents, waivers and amendments set forth above are
conditioned upon the timely delivery to the Administrative Agent of the executed
Renegy Holdings Pledge Agreement and related ancillary documents upon completion
of the Transaction as are reasonably satisfactory to and deemed necessary by the
Administrative Agent.

     5. Representations and Warranties. The Borrowers represent and warrant to
the Administrative Agent and the undersigned Lender(s) as follows:

          (a) The representations and warranties made by the Borrowers in
     Article 4 of the Credit Agreement and each other Credit Document are true
     and correct in all material respects on and as of the date hereof, except
     to the extent such representations and warranties expressly relate to an
     earlier date.

          (b) Other than as addressed herein, no Default or Event of Default has
     occurred and is continuing.

          (c) No Material Adverse Effect has occurred and is continuing.

     6. Effect of Agreement. This Agreement, together with each exhibit referred
and attached hereto, constitutes the entire and only understanding and agreement
among the parties, and supersedes all proposals, oral or written, all
negotiations, conversations or discussions among the parties, with respect to
the subject matter hereof. The execution, delivery and effectiveness of this
Agreement shall not, except as expressly provided herein, operate as a waiver of
any right, power or remedy of the Administrative Agent.

     7. Headings. The headings in this Agreement are for convenience of
reference only and are not part of the substance hereof.

     8. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York, without reference to rules of
conflicts of laws (other than Section 5-1401 of the New York General Obligations
Law).

     9. Enforceability. Should any one or more of the provisions of this
Agreement be determined to be illegal or unenforceable as to one or more of the
parties hereto, all other provisions nevertheless shall remain effective and
binding on the parties hereto.

     10. Counterparts. This Agreement may be executed in multiple originals and
by counterpart.

                            [Signature Page Follows]


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     IN WITNESS HEREOF, the parties have caused this Agreement to be duly
executed by their officers duly authorized as of the date first above written.

                                        SNOWFLAKE WHITE MOUNTAIN POWER, LLC,
                                        as Borrower


                                        By: /s/ Robert M. Worsley
                                            ------------------------------------
                                        Name: Robert M. Worsley
                                        Title: Manager


                                        RENEGY, LLC,
                                        as Borrower


                                        By: /s/ Robert M. Worsley
                                            ------------------------------------
                                        Name: Robert M. Worsley
                                        Title: Manager


                                        RENEGY TRUCKING, LLC,
                                        as Borrower


                                        By: /s/ Robert M. Worsley
                                            ------------------------------------
                                        Name: Robert M. Worsley
                                        Title: Manager


                                        COBANK, ACB,
                                        as Administrative Agent and a Lender


                                        By: /s/ David B. Willis
                                            ------------------------------------
                                        Name: David B. Willis
                                        Title: Managing Director, Energy
                                               Services, Communications and
                                               Energy Banking Group