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                                                                   Exhibit 10.35
                                SPONSOR GUARANTY

     This SPONSOR GUARANTY ("GUARANTY"), dated as of September 1, 2006, is
entered into by and between Robert M. Worsley and Christi M. Worsley
(individually, a "GUARANTOR" and collectively, "GUARANTORS") and CoBank, ACB, as
Administrative Agent under the Credit Agreement, as defined below (together with
its successors, designees and assigns in such capacity, "ADMINISTRATIVE AGENT").

     WHEREAS, Snowflake White Mountain Power, LLC ("SWMP"), Renegy, LLC
("Renegy") and Renegy Trucking, LLC (together with SWMP and Renegy,
"BORROWERS"), Administrative Agent, CoBank ACB as Collateral Agent, the LC
Issuer as defined therein, and the Lenders party thereto have entered into that
certain Credit Agreement, dated as of September 1, 2006 (the "Credit
Agreement"), pursuant to which the Lenders have agreed to extend credit to
Borrowers;

     WHEREAS, Guarantors are principals of SWMP and Guarantors expect to benefit
as a result of Lenders extending the credit and other financial accommodations
provided to Borrowers pursuant to the Credit Agreement; and

     WHEREAS, Guarantors are entering into this Guaranty as an inducement to
Lenders to enter into the Credit Agreement and other Credit Documents (such term
and each other term used but not defined herein has the meaning given to it in
Exhibit A of the Credit Agreement), with knowledge that the Lenders will rely
hereon.

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

     1. GUARANTY. Guarantors hereby jointly and severally unconditionally,
irrevocably, continuously, and absolutely guarantee to Administrative Agent
payment of the following obligations, should they arise, in connection with the
Borrowers' business activities (collectively, the "GUARANTEED OBLIGATIONS"):

          (a) If Project Costs which are necessary to achieve Completion exceed
budgeted Project Costs of $67,310,572, Guarantors shall pay such excess amount
to SWMP in sufficient time for SWMP to be able to pay the applicable Projects
Costs.

          (b) Certain insurance coverages were recommended by the Insurance
Consultant, as set forth on Exhibit A (the "Missing Coverages"), but were not
available to the Borrowers, or not available on commercially reasonable terms.
If a casualty or other event occurs which would have been covered by the Missing
Coverages, Guarantors shall contribute to SWMP, within two Business Days of
demand by Administrative Agent, such amount as Administrative Agent in
consultation with the Insurance Consultant reasonably determines would have been
payable by the provider of the applicable Missing Coverage if it had been in
place.

          (c) In the event that liquidated damages are payable by B&W pursuant
to Section 19 of the Boiler Purchase Contract, Administrative Agent in
consultation with the

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Independent Engineer shall input into the Base Case Project Projections the
as-tested boiler output upon which are based such liquidated damages, and shall
then determine the debt level which the Project could support keeping all
coverage ratios and other assumptions in the Base Case Project Projections
constant. The difference between the originally-provided debt level and such
revised debt level is the "Performance Shortfall Prepayment Amount". Guarantors
shall contribute to SWMP, within two Business Days of demand by Administrative
Agent, the difference between the Performance Shortfall Prepayment Amount and
the liquidated damages paid by B&W, and such contribution shall be applied to
prepay Construction Loans (or Term Loans, if Term-Conversion has occurred), or
Renegy Term Loans, as determined by Administrative Agent.

          (d) In connection with disbursement of each Construction Loan, an
analysis is performed as to "Available Construction Funds," as defined in the
Credit Agreement, to pay Project Costs. If such analysis projects that Available
Construction Funds will be insufficient to make the $500,000 payment owed by
SWMP to Abitibi pursuant to Section 4.2 of the Ground Lease, or if,
notwithstanding earlier projections, Available Construction Funds are in fact
insufficient to make such payment, Guarantors shall contribute to SWMP, within
two Business Days of demand by Administrative Agent, the amount necessary to
make up the shortfall, up to $500,000 in the aggregate.

          (e) In the event that on any Interest Payment Date (as defined in the
Indenture), sufficient funds are not available in the Revenue Account to
reimburse the LC Issuer for a draw under the Letter of Credit in respect of
interest on the Bonds, Guarantors shall contribute to SWMP, within two Business
Days of demand by Administrative Agent, the amount necessary to make up the
shortfall, up to $911,891 in the aggregate for all such Interest Payment Dates.

     2. GUARANTY ABSOLUTE. The liability of Guarantors under this Guaranty shall
be absolute, continuous, and unconditional irrespective of:

          (a) any lack of validity or enforceability of or defect or deficiency
in this Guaranty, any other Credit Document or any other documents to which any
Borrower and/or either Guarantor is or may become a party;

          (b) any modification, extension or waiver of any of the terms of this
Guaranty or any other Credit Document;

          (c) any existence, value or condition of, or failure to perfect the
Collateral Agent's Lien against, any Collateral or any action or the absence of
any action, by any Secured Party in respect thereof (including, without
limitation, the release of any such security);

          (d) except as to applicable statutes of limitation, failure, omission,
delay, waiver or refusal by any Secured Party to exercise, in whole or in part,
any right or remedy held by such Secured Party with respect to this Guaranty or
any other Credit Document;

          (e) any change in the existence, structure or ownership of any
Borrower, or any insolvency, bankruptcy, reorganization or other similar
proceeding affecting any Borrower or its assets; or


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          (f) any other circumstance that might otherwise constitute a defense
available to, or a discharge of, Guarantors in respect of the Guaranteed
Obligations, other than payment in full of the Guaranteed Obligations.

     3. OBLIGATIONS SEVERAL. This is a guaranty of payment and not of
collection. The obligations of Guarantors hereunder are several from the
Borrowers or any other person, and are primary obligations concerning which
Guarantors are the principal obligors. There are no conditions precedent to the
enforcement of this Guaranty, except as expressly contained herein. It shall not
be necessary for Administrative Agent, in order to enforce payment by Guarantors
under this Guaranty, to show any proof of any Borrower's default, to exhaust its
remedies against Borrowers, any other guarantor, or any other person liable for
the payment or performance of the Guaranteed Obligations. Administrative Agent
shall not be required to mitigate damages or take any other action to reduce,
collect, or enforce the Guaranteed Obligations other than under Section 9
hereof.

     4. OBLIGATIONS CONTINUING. This Guaranty shall continue to be effective or
be reinstated, as the case may be, if at any time any payment of any of the
Guaranteed Obligations are annulled, set aside, invalidated, declared to be
fraudulent or preferential, rescinded or must otherwise be returned, refunded or
repaid by Administrative Agent upon the insolvency, bankruptcy, dissolution,
liquidation or reorganization of any Borrower or any other guarantor, or upon or
as a result of the appointment of a receiver, intervener or conservator of, or
trustee or similar officer for, any Borrower or any other guarantor or any
substantial part of its property or otherwise, all as though such payment or
payments had not been made.

     5. ENFORCEMENT OF GUARANTY. In no event shall Administrative Agent have any
obligation (although it is entitled, at its option) to proceed against Borrowers
or any Collateral before seeking satisfaction from Guarantors, and
Administrative Agent may proceed, prior or subsequent to, or simultaneously
with, the enforcement of Administrative Agent's rights hereunder, to exercise
any right or remedy which it may have against any Collateral, as a result of any
Lien it may have as security for all or any portion of the Guaranteed
Obligations.

     6. WAIVER. Guarantors hereby waive:

          (a) notice of acceptance of this Guaranty, of the creation or
existence of any of the Guaranteed Obligations and of any action by
Administrative Agent in reliance hereon or in connection herewith;

          (b) except as expressly set forth herein, presentment, demand for
payment, notice of dishonor or nonpayment, protest and notice of protest with
respect to the Guaranteed Obligations; and

          (c) any requirement that suit be brought against, or any other action
by Administrative Agent be taken against, or any notice of default or other
notice be given to, or any demand be made on, Borrowers or any other Person, or
that any other action be taken or not taken as a condition to Guarantors'
liability for the Guaranteed Obligations under this Guaranty or as a condition
to the enforcement of this Guaranty against Guarantors.


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     7. EXPENSES. Guarantors agree to pay on demand any and all costs, including
reasonable legal fees, and other expenses incurred by Administrative Agent in
enforcing Guarantors' obligations under this Guaranty. Guarantors hereby
unconditionally, absolutely and irrevocably agree to hold Administrative Agent
and its successors and assigns harmless and to indemnify Administrative Agent
and its successors and assigns from and against any and all costs and expenses,
including reasonable attorneys' fees, arising out of or relating to any failure
by Guarantors to carry out, observe and perform in accordance with this Guaranty
any of Guaranteed Obligations contained in or arising from this Guaranty.

     8. BENEFIT OF GUARANTY. The provisions of this Guaranty are for the benefit
of the Secured Parties and their successors, transferees, endorsees and assigns.

     9. MODIFICATION OF GUARANTEED OBLIGATIONS, ETC. Guarantors hereby
acknowledge and agree that Administrative Agent may at any time or from time to
time, with or without the consent of, or notice to, Guarantors:

          (a) take any action under or in respect of the Credit Documents in the
exercise of any remedy, power or privilege contained therein or available to it
at law, equity or otherwise, or waive or refrain from exercising any such
remedies, powers or privileges;

          (b) amend or modify the Credit Documents;

          (c) extend or waive the time for Borrowers' performance of, or
compliance with, any term, covenant or agreement on its part to be performed or
observed under the Credit Documents, or waive such performance or compliance or
consent to a failure of, or departure from, such performance or compliance;

          (d) release anyone who may be liable in any manner for the payment of
any amounts owed by Guarantors or Borrowers to the Secured Parties; and/or

          (e) modify or terminate the terms of any intercreditor or
subordination agreement pursuant to which claims of other creditors of
Guarantors or Borrowers are subordinated to the claims of the Secured Parties;

and the Secured Parties shall not incur any liability to Guarantors as a result
thereof, and no such action shall impair or release the Guaranteed Obligations
of Guarantors under this Guaranty.

     10. SUBROGATION. Guarantors hereby waive any right of subrogation they
otherwise might have had against Borrowers.

     11. REINSTATEMENT. This Guaranty shall remain in full force and effect and
continue to be effective should any petition be filed by or against Borrowers or
either Guarantor for liquidation or reorganization, should Borrowers or either
Guarantor become insolvent or make an assignment for the benefit of creditors or
should a receiver or trustee be appointed for all or any significant part of the
Borrowers' or Guarantors' assets, and shall continue to be effective or be
reinstated, as the case may be, if at any time payment and performance of the
Guaranteed Obligations, or any part thereof, is, pursuant to applicable law,
rescinded or reduced in amount, or must otherwise be restored or returned by
Administrative Agent, whether as a "voidable


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preference", "fraudulent conveyance", or otherwise, all as though such payment
or performance had not been made. In the event that any payment, or any part
thereof, is rescinded, reduced, restored or returned, the Guaranteed Obligations
shall be reinstated and deemed reduced only by such amount paid and not so
rescinded, reduced, restored or returned.

     12. ELECTION OF REMEDIES. If Administrative Agent may, under applicable
law, proceed to realize benefits under any of the Credit Documents giving
Administrative Agent a Lien upon any Collateral owned by Borrowers, either by
judicial foreclosure or by non-judicial sale or enforcement, Administrative
Agent may, at its sole option, determine which of such remedies or rights it may
pursue without affecting any of such rights and remedies under this Guaranty.

     13. CONTINUING GUARANTY. This is a continuing Guaranty, and all extensions
of credit and financial accommodations concurrently herewith or hereafter made
by the Secured Parties to Borrowers and all indebtedness of Borrowers now owned
or hereafter acquired by the Secured Parties in connection with the transactions
contemplated under the Credit Agreement shall be conclusively presumed to have
been made or acquired in acceptance hereof.

     14. NOTICES. All demands, notices and other communications provided for
hereunder shall, unless otherwise specifically provided herein, (a) be in
writing addressed to the party receiving the notice at the address set forth
below or at such other address as may be designated by written notice, from time
to time, to the other party, and (b) be effective upon delivery, when mailed by
U.S. mail, registered or certified, return receipt requested, postage prepaid,
or personally delivered. Notices shall be sent to the following addresses:

     If to Administrative Agent:

     5500 S. Quebec Street
     Greenwood Village, CO 80111
     Attention: David B. Willis, copy to Kelly Purtell
     Facsimile No.: (303) 796-1437
     Telephone No.: (303) 740-6513

     If to Guarantors:

     Robert M. Worsley
     Christi M. Worsley
     3418 N. Val Vista Drive
     Mesa, AZ 85213
     Telephone: (480)219-1063
     Facsimile: (480)718-7977


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     If to Borrowers:

     Snowflake White Mountain Power, LLC
     3418 N. Val Vista Drive
     Mesa, AZ 85213
     Attention: Robert M. Worsley
     Telephone: (480)219-1063
     Facsimile: (480)718-7977

     15. NO WAIVER; REMEDIES. Except as to applicable statutes of limitation, no
failure on the part of Administrative Agent to exercise, and no delay in
exercising, any right hereunder shall operate as a waiver thereof, nor shall any
single or partial exercise of any right hereunder preclude any other or further
exercise thereof or the exercise of any other right. The remedies herein
provided are cumulative and not exclusive of any remedies provided by law.

     16. TERM; TERMINATION. This Guaranty shall continue in full force and
effect until payment in full of the Obligations, cancellation of the
Commitments, and return for cancellation of the Letter of Credit; provided,
however, that the obligations and liabilities of Guarantors hereunder shall
continue in full force and effect with respect to any breach of its obligations
hereunder or of the Guaranteed Obligations, in each case occurring prior to such
termination; provided further, that (a) if the Borrowers are able to obtain the
Missing Coverages, Section 1(b) of this Guaranty shall terminate and have no
further force and effect from and after such time as the Missing Coverages are
in place, otherwise, Section 1(b) of this Guaranty shall terminate and have no
further force and effect upon Term-Conversion, (b) Section 1(c) of this Guaranty
shall terminate and have no further force and effect if either (i) no liquidated
damages are payable by B&W pursuant to Section 19 of the Boiler Purchase
Contract upon Term-Conversion, (ii)the Performance Shortfall Payment Amount is
zero upon Term-Conversion, or (iii) the Performance Shortfall Prepayment Amount
shall have been paid and applied per Section 1(c) hereof, upon such application,
(c) Sections 1(a) and 1(d) of this Guaranty shall terminate and have no further
force and effect upon Term-Conversion; and (d) Section 1(e) of this Guaranty
shall terminate and have no further force and effect upon payment of shortfalls
described therein in an aggregate amount of $911,891 or the repayment in full in
cash of the Obligations.

     17. SUCCESSORS AND ASSIGNS. This Guaranty shall be binding upon and inure
to the benefit of the parties hereto and their respective heirs, successors,
assigns, and legal representatives.

     18. AMENDMENTS, ETC. No amendment of this Guaranty shall be effective
unless in writing and signed by Guarantors and Administrative Agent. No waiver
of any provision of this Guaranty nor consent to any departure by Guarantors
therefrom shall in any event be effective unless such waiver shall be in writing
and signed by Administrative Agent. Any such waiver shall be effective only in
the specific instance and for the specific purpose for which it was given.

     19. CAPTIONS. The captions in this Guaranty have been inserted for
convenience only and shall be given no substantive meaning or significance
whatsoever in construing the terms and provisions of this Guaranty.


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     20. REPRESENTATION AND WARRANTIES. Guarantors represent and warrant that
this Guaranty constitutes the legal, valid and binding obligation of Guarantors
enforceable against Guarantors in accordance with its terms, subject, as to
enforcement, to bankruptcy, insolvency and other laws of general applicability
relating to or affecting the rights of creditors and to general equity
principles.

     21. LIMITATION BY LAW. All rights, remedies and powers provided in this
Guaranty may be exercised only to the extent that the exercise thereof does not
violate any applicable provision of law, and all the provisions of this Guaranty
are intended to be subject to all applicable mandatory provisions of law that
may be controlling and to be limited to the extent necessary so that they will
not render this Guaranty invalid, unenforceable, in whole or in part, or not
entitled to be recorded, registered or filed under the provisions of any
applicable law. In the event that any provision of this Guaranty is held to be
invalid or unenforceable in whole or in part by any court of competent
jurisdiction, the remainder hereof shall continue in full force and effect, and
the affected provision shall be enforced to the extent permitted by law.

     22. GOVERNING LAW. THIS GUARANTY IS MADE UNDER AND SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF ARIZONA, EXCLUSIVE OF ANY
CONFLICT OF LAWS AND PROVISIONS THAT WOULD APPLY TO THE LAWS OF ANOTHER
JURISDICTION.

     23. WAIVER OF JURY TRIAL. EACH PARTY WAIVES, TO THE FULLEST EXTENT
PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN RESPECT
OF ANY SUIT, ACTION, CLAIM OR PROCEEDING RELATING TO THIS AGREEMENT.

     24. ENTIRE AGREEMENT. This Guaranty constitutes the entire agreement among
the parties and supersedes all prior and contemporaneous agreements and
understandings of the parties with respect to the subject matter hereof.

     25. GUARANTOR ACKNOWLEDGMENTS. Guarantors acknowledge that (i) they have
been advised by counsel in the negotiations, execution, and delivery of this
Guaranty, and (ii) Administrative Agent has no fiduciary relationship to either
Guarantor.


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     IN WITNESS WHEREOF, Guarantors have caused this Sponsor Guaranty to be duly
executed and delivered as of the date first written above.


                                        By: /s/ Robert M. Worsley
                                            ------------------------------------
                                            Robert M. Worsley


                                        By: /s/ Christi M. Worsley
                                            ------------------------------------
                                            Christi M. Worsley

                       Signature Page to Sponsor Guaranty