Exhibit 10.13 (b)
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                                  AMENDMENT TO
                                    SUBLEASE


This Amendment to Sublease (this "Amendment") is made as of March 21, 2006 by
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and between Enron Wind Systems, LLC ("EWS"), the successor by merger to Enron
                                      ---
Wind Systems, Inc., which was formerly known as Zond Systems, Inc., and Zond
Windsystem Partners, Ltd. Series 85-B, a California limited partnership (the
"Partnership").
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                                    RECITALS
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A.  WHEREAS, EWS and the Partnership are parties to that certain Sublease dated
    as of August 30, 1990 (the "Sublease"), pursuant to which EWS has subleased
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    to the Partnership fourteen (14) wind turbine site locations on land leased
    by EWS under that certain Lease and Royalty Agreement for Meteorological
    Research Sites and the Construction and Operation of Wind Energy Conversion
    Systems ( the "Lease") by and between the John M. Wuerth Family Trust and
    EWS, as successor by merger to Enron Wind Systems, Inc.


B.  WHEREAS, the term of the Sublease expires on the later to occur of (i) the
    termination of all power purchase agreements which receive power generated
    on or transmitted over the land subject to the Sublease and (ii) December
    21, 2021 (the "Sublease Termination Date").
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C.  WHEREAS, the term of that certain Amended and Restated Wind Park Easement
    Agreement dated as of March 24, 1986 (the "Wind Park Easement Agreement")
                                               ----------------------------
    by and between the Partnership and ZWHC LLC, the successor to Zond
    Construction Corporation III, a California corporation, and an affiliate of
    EWS, expires on June 30, 2006 (the "Wind Park Easement Termination Date")
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    and at such time the Partnership's rights to operate 226 of its 240 wind
    turbines will terminate.

D.  WHEREAS, the EWS and the Partnership desire to amend the Sublease
    Termination Date to be concurrent with the Wind Park Easement Termination
    Date and to provide the Partnership with a period of time following the
    Sublease Termination Date to remove its wind turbines from the real property
    subject to the Sublease.


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                                    AGREEMENT
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NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which is hereby acknowledged, ZWHC and the Partnership agree as follows:

1.   Amendment to Sublease. The Sublease is hereby amended as follows:
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     1.1  Section 4. Term. Section 4 of the Sublease is hereby amended to delete
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          the existing text of Section 4 in its entirety and replace it with the
          following:

          "The term of this Sublease shall be for a period commencing as of the
          date hereof and ending on June 30. 2006 (the "Scheduled Expiration
          Date"), provided, however, that the term of this Sublease shall
          continue beyond the Scheduled Expiration Date solely for the purposes
          specified in Section 18 pertaining to the removal of the Turbines
          until the first to occur of (i) the date of removal of the Sublessee's
          Turbines as provided in Section 18 or (ii) the date occurring eleven
          (11) months from the Scheduled Expiration Date."

     1.2  Section 18. Disposition of Turbines at Expiration of Term. The
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          Sublease is hereby amended by adding the following new Section 18:

          "18 DISPOSITION OF TURBINES AT EXPIRATION OF TERM

               Upon the occurrence of the Scheduled Expiration Date, the
          Sublessee shall have the right, but not the obligation, to remove
          during the eleven-month period immediately following the Scheduled
          Expiration Date the Turbines and/or any related turbine equipment of
          the Sublessee from the Premises at the sole cost and expense of the
          Sublessee. In the event that the Sublessee fails to remove any of its
          Turbines or turbine-related equipment from the Premises during such
          eleven-month period, then such Turbines and turbine-related equipment
          shall be deemed abandoned by the Sublessee at the end of such period
          and all right, title and interest of the Sublessee in such Turbines
          and turbine-related equipment shall pass to the Sublessor without any
          further act by Sublessee; provided, however, that the Sublessor (or
          any affiliates or assigns) shall not have the right to operate any
          such abandoned Turbines or turbine-related equipment unless the
          Sublessor (or any affiliates or assigns) shall have paid to the
          Sublessee an amount equal to the appraised fair market value of such
          abandoned Turbines and turbine related equipment (valued in place
          taking into account any expected revenues from operation) as
          determined by a qualified independent appraiser mutually acceptable to

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          the Sublessor and the Sublessee."

2. Governing Law. The terms and provisions of this Amendment shall be governed
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by and construed in accordance with the laws of the State of California.

3. Counterparts. This Amendment may be executed in counterparts, each of which
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shall be deemed an original and all of which, when taken together, shall
constitute one and the same document.

IN WITNESS WHEREOF, each of the parties to this Amendment has executed this
Amendment on the date first set forth above.





EWS                                                        Partnership
Enron Wind Systems, LLC,                                   Zond Windsystem Partners, Ltd. Series
a California limited liability company                     85-B, a California limited partnership

                                                        
By:   Enron Wind LLC,                                      By:  Zond Windsystems Management
      its sole member                                           IV LLC, its General Partner

By:   Enron Renewable Energy Corp.,                        By:     /s/ Jesse E. Neyman
      its sole member                                           ------------------------------------------
                                                           Name:   Jesse E. Neyman
                                                                 -----------------------------------------
                                                           Title:  President and Chief Executive Officer
                                                                  ----------------------------------------


By:     /s/ Jesse E. Neyman
    -----------------------------------------
Name:   Jesse E. Neyman
      ---------------------------------------
Title:  President and Chief Executive Officer
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