Exhibit 10.4

                                PROMISSORY NOTE
                                   (Due 2009)

$122,550,000.00                                                     May 28, 1999


          For value received, the undersigned, COSO FINANCE PARTNERS, a
California general partnership (the "Guarantor"), by this promissory note
                                     ---------
promises to pay to the order of Caithness Coso Funding Corp., a Delaware
corporation ("Funding Corporation"), at the office of Funding Corporation,
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located at 1114 Avenue of the Americas, New York, New York 10036, in lawful
currency of the United States of America and in immediately available funds, the
principal amount of $122,550,000.00, or if less, the aggregate unpaid and
outstanding principal amount of this Promissory Note advanced by Funding
Corporation to the Guarantor pursuant to that certain Credit Agreement (the
"Guarantor Credit Agreement"), dated as of May 28, 1999, by and among the
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Guarantor and Funding Corporation, and as the same may be amended from time to
time, and all other amounts owed by the Guarantor to Funding Corporation
hereunder.

          This is the Promissory Note entered into pursuant to the Guarantor
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 that certain Indenture,
dated as of May 28, 1999 (the "Indenture"), by and between Funding Corporation,
                               ---------
the Guarantor, Coso Energy Developers, a California general partnership, Coso
Power Developers, a California general partnership, and U.S. Bank Trust National
Association, as trustee.

          Reference is hereby made to the Guarantor Credit Agreement, the
Indenture and the Security Documents for the provisions, among others, with
respect to the rights, duties and obligations of the Guarantor and the rights of
the holder of this Promissory Note.

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

          The Guarantor further agrees to pay, in lawful currency 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 Guarantor Credit Agreement, and the Guarantor agrees to
pay other fees and costs as stated in the Guarantor Credit Agreement.

          Upon the occurrence of any one or more Credit Agreement Events of
Default (as


defined in Section 5.1 of the Guarantor Credit Agreement), all amounts then
remaining unpaid under this Promissory Note may become or be declared to be
immediately due and payable as provided in the Guarantor Credit Agreement,
without notice of default, presentment or demand for payment, protest or notice
of nonpayment or dishonor, or notices or demands of any kind, all of which are
expressly waived by the Guarantor.

          The obligations hereunder are subject to the limitations set forth in
Section 6.11 of the Guarantor Credit Agreement, the provisions of which are
hereby incorporated by reference.

          This Promissory Note shall be construed and interpreted in accordance
with and governed by the laws of the State of New York without regard to the
conflicts of laws rules thereof other than Section 5-1401 of the New York
General Obligations Law.

                       COSO FINANCE PARTNERS,
                       a California general partnership

                              By:  New CLOC Company, LLC,
                                   a Delaware limited liability company,
                                   its Managing General Partner

                                   By:  /s/ Christopher T. McCallion
                                        ----------------------------
                                        Christopher T. McCallion
                                        Executive Vice President

                              By:  ESCA, LLC,
                                   a Delaware limited liability company,
                                   its General Partner

                                   By:  /s/ Christopher T. McCallion
                                        ----------------------------
                                        Christopher T. McCallion
                                        Executive Vice President

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