FIRST AMENDMENT TO LOAN AGREEMENT

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Exhibit 10.51

FIRST AMENDMENT TO LOAN AGREEMENT

        THIS FIRST AMENDMENT TO LOAN AGREEMENT (herein called the "Amendment") made as of July 28, 2009 by and between CLEAN ENERGY, a California corporation (the "Lender") and Dallas Clean Energy, LLC., a Delaware limited liability company (formerly CE Dallas Renewables LLC) (the "Borrower").

W I T N E S S E T H:

        WHEREAS, the Borrower and Lender entered into that certain Loan Agreement dated as of August 15, 2008 (as amended, supplemented, or restated to the date hereof, the "Original Loan Agreement"), for the purpose and consideration therein expressed, whereby Lender became obligated to make loans to the Borrower as therein provided; and

        WHEREAS, the Borrower and Lender desire to amend the Original Loan Agreement as set forth herein;

        NOW, THEREFORE, in consideration of the premises and the mutual covenants and agreements contained herein and in the Original Loan Agreement, in consideration of the loans which may hereafter be made by Lender to the Borrower, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto do hereby agree as follows:

ARTICLE I.

DEFINITIONS AND REFERENCES

        § 1.1.     Terms Defined in the Original Loan Agreement.     Unless the context otherwise requires or unless otherwise expressly defined herein, the terms defined in the Original Loan Agreement shall have the same meanings whenever used in this Amendment.

        § 1.2.     Other Defined Terms.     Unless the context otherwise requires, the following terms when used in this Amendment shall have the meanings assigned to them in this Section 1.2.

        " Amendment " means this First Amendment to Original Loan Agreement.

        " Loan Agreement " means the Original Loan Agreement as amended hereby.

ARTICLE II.

AMENDMENTS TO ORIGINAL LOAN AGREEMENT

        § 2.1.     Recitals.     Section D of the Original Loan Agreement is hereby amended in its entirety to read as follows:

        "In order to fund certain capital improvements to be made in connection with the process of repairing, improving, expanding and operating the Project or to provide capital for other uses as Lender may consent to in its sole discretion, Borrower has requested that Lender provide secured financing to Borrower in an aggregate principal amount of up to $14,000,000."

        § 2.2.     Repayment Terms.     Section 1.1(c) of the Original Loan Agreement is hereby amended in its entirety to read as follows:

        "Lender shall have received evidence from Borrower, in form and substance satisfactory to Lender, that Borrower will use the proceeds of each requested Loan for capital improvements identified on Schedule 1.1, prior expenditures for the drilling and installation of gas collection wells, such other capital expenditures, working capital or other uses (including repayment of principal due under this Agreement) as Lender may consent to in its sole discretion."

ARTICLE III.

CONDITIONS OF EFFECTIVENESS

        § 3.1.     Effective Date.     This Amendment shall become effective as of the date first above written when and only when:

        (a)   Lender shall have received all of the following, at Lender's office, duly executed and delivered and in form and substance satisfactory to Lender, all of the following:

        (i)    the Amendment; and

        (ii)   such other supporting documents as Lender may reasonably request.

        (b)   The Borrower shall have paid all other fees and reimbursements to be paid to Lender pursuant to the Original Loan Agreement or otherwise due Lender including fees and disbursements of Lender's attorneys.

ARTICLE IV.

REPRESENTATIONS AND WARRANTIES

        § 4.1.     Representations and Warranties of the Borrower.     In order to induce Lender to enter into