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                                                                   Exhibit 10.28

                                CONSTRUCTION NOTE

$12,001,890                                                   New York, New York
Note No. 1                                                      September 8,2006

     For value received, the undersigned, SNOWFLAKE WHITE MOUNTAIN POWER, LLC,
an Arizona limited liability company, RENEGY, LLC, an Arizona limited liability
company, and RENEGY TRUCKING, LLC, an Arizona limited liability company
(collectively, "Borrowers"). unconditionally jointly and severally promise to
pay to Cobank, ACB ("Lender"), at the office of CoBank, ACB, acting as
Administrative Agent under the Credit Agreement described below, located at 5500
S. Quebec Street, Greenwood Village, CO 80111, in lawful money of the United
States of America and in immediately available funds, the principal amount of
TWELVE MILLION ONE THOUSAND EIGHT HUNDRED NINETY DOLLARS ($12,001,890), or if
less, the aggregate unpaid and outstanding principal amount of the Construction
Loans advanced by Lender to Borrowers pursuant to that certain Credit Agreement,
dated as of September 1, 2006 (as amended, supplemented or otherwise modified
from time to time, the "Credit Agreement"), by and among Borrowers, Cobank, ACB,
as letter of credit issuer, CoBank, ACB, as lead arranger, administrative agent
and collateral agent, and Lender and the other financial institutions from time
to time parties thereto as lenders (collectively, the "Lenders"), and all other
amounts owed by Borrowers to Lender hereunder.

     This is one of the Construction Notes referred to in the Credit Agreement
and is entitled to the benefits thereof and is subject to all terms, provisions
and conditions thereof. Capitalized terms used and not defined herein shall have
the meanings set forth in the Credit Agreement.

     This Construction Note is made in connection with and is secured by, among
other instruments, the provisions of the Collateral Documents. Reference is
hereby made to the Credit Agreement and the Collateral Documents for the
provisions, among others, with respect to the custody and application of the
Collateral, the nature and extent of the security provided thereunder, the
rights, duties and obligations of Borrowers and the rights of the holder of this
Construction Note.

     The principal amount hereof is payable in accordance with the Credit
Agreement, and such principal amount may be prepaid solely in accordance with
the Credit Agreement.

     Borrowers further agree to pay, in lawful money of the United States of
America and in immediately available funds, interest from the date hereof on the
unpaid and outstanding principal amount hereof until such unpaid and outstanding
principal amount shall become due and payable (whether at stated maturity, by
acceleration or otherwise) at the rates of interest and at the times set forth
in the Credit Agreement, and Borrowers agree to pay all other fees and costs
owed to Lender under the Credit Agreement at the times specified in, and
otherwise in accordance with, the Credit Agreement.

     If any payment on this Construction Note becomes due and payable on a date
which is not a Business Day, such payment shall be made on the preceding or next
succeeding Business Day, in either case in accordance with the terms of the
Credit Agreement.

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     Upon the occurrence and during the continuation of any one or more Events
of Default, all amounts then remaining unpaid on this Construction Note may
become or be declared to be immediately due and payable as provided in the
Credit Agreement and the other Credit Documents. Borrowers hereby expressly
waive notice of default, presentment or demand for payment, protest or notice of
nonpayment or dishonor, or notices or demands of any kind.

     Recourse under this Construction Note shall be limited as provided in
Article 9 of the Credit Agreement.

     Borrowers agree to pay costs and expenses of Lender, including attorneys'
fees, incurred in connection with the interpretation or enforcement of this
Construction Note, at the times specified in, and otherwise in accordance with,
the Credit Agreement.

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     THIS CONSTRUCTION NOTE HAS BEEN EXECUTED AND DELIVERED IN AND SHALL BE
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE
STATE OF NEW YORK, WITHOUT REFERENCE TO CONFLICTS OF LAWS (OTHER THAN SECTIONS
5-1401 AND 5-1402 OF THE NEW YORK GENERAL OBLIGATIONS LAW).

                                        SNOWFLAKE WHITE MOUNTAIN POWER, LLC,


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


                                        RENEGY, LLC


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


                                        RENEGY TRUCKING, LLC


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

                       Signature Page to Construction Note