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                                                                   EXHIBIT 10.15

                                                                  EXECUTION COPY

                       AFFILIATED PARTY AGREEMENT GUARANTY

                  This AFFILIATED PARTY AGREEMENT GUARANTY (this "Guaranty")
dated as of March 23, 2004 is made by CALPINE CORPORATION, a Delaware
corporation ("Guarantor"), in favor of CALPINE GENERATING COMPANY, LLC, a
Delaware limited liability company ("CGC"), and the indirect wholly-owned
subsidiaries of CGC listed on Exhibit A attached hereto or that becomes a
beneficiary of this Guaranty as provided in Section 1(a) (each a "Facility
Owner").

                                    RECITALS

                  A.       Calpine Energy Services, L.P., a Delaware limited
partnership ("CBS"), is party to (i) that certain Index Based Gas Sale and Power
Purchase Agreement dated as of March 23, 2004 by and between CES, CGC and the
Facility Owners, and (ii) that certain WECC Fixed Price Gas Sale and Power
Purchase Agreement dated as March 23, 2004, by and between CES, CGC and certain
Facility Owners. Calpine Operating Services Company, Inc., a Delaware
corporation ("COSCI"), is party to (1) that certain Master Operation and
Maintenance Agreement dated as of March 23, 2004, and (2) that certain Master
Maintenance Services Agreement dated as of March 23, 2004, each by and between
COSCI, CGC and the Facility Owners. Calpine Construction Management Company,
Inc., a Delaware limited partnership ("CCMCI"), is party to (a) that certain
Master Construction Management Agreement, dated as of March 23, 2004, by and
between CCMCI, CGC and the Facility Owners and (b) that certain Contract for
Construction dated as of July 1, 2003 by and between CCMCI and Pastoria Energy
Facility L.L.C. (the "Pastoria Construction Contract"). Calpine Administrative
Services Company, Inc., a Delaware corporation ("CASCI") is party to that
certain Administrative Services Agreement dated as of March 23, 2004 by and
amongCASCI, CGC and the Facility Owners. The agreements described in this
Recital A are referred to collectively as the "Relevant Documents," and CES,
COSCI, CCMCI and CASCI are referred to collectively as the "Affiliated Parties;"

                  B.       Guarantor owns, either directly or indirectly, 100%
of the outstanding capital stock or other equity interests of each of the
Affiliated Parties;

                  C.       CGC and the Facility Owners have agreed to enter into
the Relevant Documents on the condition that Guarantor guarantee certain of the
Affiliated Parties' obligations thereunder as provided herein (or, in the case
of the Pastoria Construction Contract, on the condition that Guarantor guarantee
obligations thereunder pursuant to a past guaranty that is being terminated and
replaced by this Guaranty as of the date hereof);

                  D.       Guarantor acknowledges that it has and will benefit,
directly and indirectly, if CGC and the Facility Owners enter into the Relevant
Documents; and

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                  E.       The obligations of Guarantor hereunder are being
incurred concurrently with the obligations of the Affiliated Parties under the
Relevant Documents (or, in the case of the Pastoria Construction Contract, the
obligations of Guarantor under the past guaranty being terminated as of the date
hereto, were incurred concurrently with the obligations of CCMCI under the
Pastoria Construction Contract).

                                    AGREEMENT

                  NOW, THEREFORE, in consideration of the premises set forth
above and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, Guarantor hereby consents and agrees as follows:

         1.       Guaranty.

                  (a)      The undersigned Guarantor, as primary obligor and not
merely as surety, unconditionally and irrevocably guarantees to CGC and the
Facility Owners payment and performance when due, whether by acceleration or
otherwise, of any and all obligations and liabilities of each of the Affiliated
Parties under the Relevant Documents, together with all expenses incurred by CGC
and the Facility Owners in enforcing any of such obligations and liabilities or
the terms hereof, including, without limitation, reasonable fees and expenses of
legal counsel (collectively, the "Obligations"), and agrees that if for any
reason any of the Affiliated Parties shall fail to pay or perform when due any
of such Obligations, Guarantor will pay or perform the same forthwith (it being
understood that Guarantor's liability hereunder shall be subject to the same
limitations of liability as the Affiliated Parties' liability under the Relevant
Documents). Guarantor waives notice of acceptance of this Guaranty and of any
obligation to which it applies or may apply under the terms hereof, and waives
diligence, presentment, demand of payment, notice of dishonor or non-payment,
protest, notice of protest, of any such obligations, suit or taking other action
by CGC and the Facility Owners against, and giving any notice of default or
other notice to, or making any demand on, any party liable thereon (including
Guarantor). Guarantor further agrees that, in the event (i) any Facility Owners
not listed on Exhibit A are added to or become parties to any of the Relevant
Documents, such added or new Facility Owners shall be considered "Facility
Owners" hereunder and (ii) any directly or indirectly wholly-owned subsidiary of
Guarantor enters into a "general" or "prime" construction contract for the
design and construction of an electric generating facility (a "Facility") owned
by a Facility Owner or the expansion of a Facility owned by a Facility Owner,
such directly or indirectly wholly-owned subsidiary of Guarantor shall be
considered an "Affiliated Party" hereunder and such "general" or "prime"
construction contract shall be considered a "Relevant Document" hereunder.

                  (b)      This Guaranty is a primary obligation of the
Guarantor and is an absolute, unconditional, continuing and irrevocable guaranty
of payment and performance and not of collectibility and is in no way
conditioned on or contingent upon any attempt to enforce in whole or in part any
of the Affiliated Parties' liabilities and obligations to CGC and the Facility
Owners. If any of the Affiliated Parties shall fail to pay or perform any of the
Obligations to CGC or any Facility Owner as and when they are due, Guarantor
shall forthwith pay or perform, as applicable, such Obligations. Any and all
payments by Guarantor hereunder shall be in immediately available funds. Each
failure by any of the Affiliated Parties to pay or perform any

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Obligations shall give rise to a separate cause of action herewith, and separate
suits may be brought hereunder as each cause of action arises.

                  (c)      CGC and the Facility Owners may, at any time and from
time to time (whether or not after revocation or termination of this Guaranty)
without the consent of or notice to Guarantor, except such notice as may be
required by the Relevant Documents or applicable law which cannot be waived,
without incurring responsibility to Guarantor and without impairing or releasing
the obligations of Guarantor hereunder, upon or without any terms or conditions
and in whole or in part, (i) change the manner, place and terms of payment or
performance or change or extend the time of payment of, renew, or alter any
Obligation, or any obligations and liabilities (including any of those
hereunder) incurred directly or indirectly in respect thereof or hereof or in
any manner modify, amend or supplement the terms of the Relevant Documents, any
documents, instruments or agreements executed in connection therewith, in each
case with the consent of the relevant Affiliated Parties, if required by the
Relevant Documents, and the guaranty herein made shall apply to the Obligations,
changed, extended, renewed, modified, amended, supplemented or altered in any
manner; (ii) exercise or refrain from exercising any rights against any of the
Affiliated Parties or others (including Guarantor) or otherwise act or refrain
from acting; (iii) add or release any other guarantor from its obligations
without affecting or impairing the obligations of Guarantor hereunder; (iv)
settle or compromise any Obligations and/or any obligations and liabilities
(including any of those hereunder) incurred directly or indirectly in respect
thereof or hereof, and may subordinate the payment of all or any part thereof to
the payment of any obligations and liabilities which may be due to CGC and/or
the Facility Owners or others; (v) sell, exchange, release, surrender, realize
upon or otherwise deal with in any manner or in any order any property by
whomsoever pledged or mortgaged to secure or howsoever securing the Obligations
or any liabilities or obligations (including any of those hereunder) incurred
directly or indirectly in respect thereof or hereof and/or any offset
thereagainst; (vi) apply any sums by whomsoever paid or howsoever realized to
any obligations and liabilities of any of the Affiliated Parties to CGC and/or
the Facility Owners under the Relevant Documents in the manner provided therein
regardless of what obligations and liabilities remain unpaid; (vii) consent to
or waive any breach of, or any act, omission or default under, the Relevant
Documents or otherwise amend, modify or supplement (with the consent of the
relevant Affiliated Parties, if required by the Relevant Documents) the Relevant
Documents or any of such other instruments or agreements; and/or (viii) act or
fail to act in any manner referred to in this Guaranty which may deprive
Guarantor of its right to subrogation against any of the Affiliated Parties to
recover full indemnity for any payments made pursuant to this Guaranty or of its
right of contribution against any other party.

                  (d)      No invalidity, irregularity or unenforceability of
the obligations or liabilities hereby guaranteed shall affect, impair, or be a
defense to this Guaranty, which is a primary obligation of Guarantor.

                  (e)      This is a continuing Guaranty and all obligations to
which it applies or may apply under the terms hereof shall be conclusively
presumed to have been created in reliance hereon. In the event that,
notwithstanding the provisions of Section 1(a) hereof, this Guaranty shall be
deemed revocable in accordance with applicable law, then any such revocation
shall become effective only upon receipt by CGC and the Facility Owners of
written notice of revocation signed by Guarantor. No revocation or termination
hereof shall affect in any manner rights arising under this Guaranty with
respect to Obligations (i) arising prior to receipt by CGC

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and the Facility Owners of written notice of such revocation or termination and
the sole effect of revocation and termination hereof shall be to exclude from
this Guaranty Obligations thereafter arising which are unconnected with
Obligations theretofore arising or transactions theretofore entered into or (ii)
arising as a result of a default under the Relevant Documents occurring by
reason of the revocation or termination of this Guaranty.

                  (f)      (i) Except as otherwise required by law, each payment
required to be made by Guarantor to CGC and/or the Facility Owners hereunder
shall be made without deduction or withholding for or on account of Taxes. If
such deduction or withholding is so required, Guarantor shall, upon notice
thereof from CGC and/or the Facility Owners, (A) pay the amount required to be
deducted or withheld to the appropriate authorities before penalties attach
thereto or interest accrues thereon, (B) on or before the 60th day after payment
of such amount, forward to CGC and the Facility Owners, as applicable, an
official receipt evidencing such payment (or a certified copy thereof), and (C)
in the case of any such deduction or withholding, forthwith pay to CGC and/or
the Facility Owners, as applicable, such additional amount as may be necessary
to ensure that the net amount actually received by CGC and the Facility Owners
is free and clear of such Taxes, including any Taxes on such additional amount,
is equal to the amount that CGC and/or the Facility Owners would have received
had there been no such deduction or withholding.

                           (ii)     As used herein, the term "Tax" means any
present or future tax, levy, impost, duty, charge, assessment or fee of any
nature (including interest, penalties and additions thereto) that is imposed by
any government or other taxing authority in respect of any payment under this
Guaranty other than any income, franchise or similar tax imposed upon the gross
or net income of CGC or the Facility Owners by the United States or any State or
any jurisdiction where CGC or the Facility Owners, as applicable, are organized
and/or the jurisdiction in which any of them is located.

         2.       Representations and Warranties. Guarantor makes the
representations and warranties set forth below to CGC and the Facility Owners as
of the date hereof:

                  (a)      Guarantor is duly formed, validly existing and in
good standing under the laws of the State of Delaware and has the power and
authority to execute and deliver this Guaranty and to perform its obligations
hereunder.

                  (b)      Guarantor has taken all necessary corporate action to
authorize the execution and delivery of this Guaranty and the performance of its
obligations hereunder.

                  (c)      All governmental authorizations and actions necessary
in connection with the execution and delivery by Guarantor of this Guaranty and
the performance of its obligations hereunder have been obtained or performed and
remain valid and in full force and effect.

                  (d)      This Guaranty has been duly executed and delivered by
Guarantor and constitutes the legal, valid and binding obligation of Guarantor,
enforceable against Guarantor in accordance with the terms of this Guaranty,
subject to applicable bankruptcy, insolvency and other similar laws affecting
creditors' rights generally.

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                  (e)      The execution, delivery and performance of this
Guaranty (i) do not and will not contravene any provisions of Guarantor's
certificate of incorporation or bylaws, or any law, rule, regulation, order,
judgment or decree applicable to or binding on Guarantor or any of its
affiliates or properties; (ii) do not and will not contravene, or result in any
breach of or constitute any default under, any material agreement or instrument
to which Guarantor is a party or by which Guarantor or any of its properties may
be bound or affected; and (iii) do not and will not require the consent of any
person under any existing law or agreement which has not already been obtained.

                  (f)      Guarantor is not an investment company or a company
controlled by an investment company, within the meaning of the Investment
Company Act of 1940, and is not subject to, or is exempt from, regulation under
the Public Utility Holding Company Act of 1935 and the Federal Power Act.

                  (g)      Guarantor has established adequate means of obtaining
financial and other information pertaining to the businesses, operations and
condition (financial and otherwise) of each of the Affiliated Parties and their
respective properties on a continuing basis, and Guarantor now is and hereafter
will be completely familiar with the businesses, operations and condition
(financial and otherwise) of each of the Affiliated Parties and their respective
properties.

                  (h)      (i) Guarantor is not, and will not as a result of the
execution and delivery of this Guaranty, be rendered insolvent, (ii) Guarantor
does not intend to incur, or believe it is incurring, obligations beyond its
ability to pay and (iii) Guarantor's property remaining after the delivery and
performance of this Guaranty will not constitute unreasonably small capital.

         3.       Covenants. So long as any Obligations are outstanding,
Guarantor agrees that:

                  (a)      It will maintain in full force and effect all
consents of any governmental or other authority that are required to be obtained
by it with respect to this Guaranty and will obtain any that may become
necessary in the future;

                  (b)      It will comply in all material respects with all
applicable laws and orders to which it may be subject if failure so to comply
would materially impair its ability to perform its obligations under this
Guaranty;

                  (c)      It will deliver such other documents and other
information reasonably requested by CGC or any Facility Owner; and

                  (d)      It will comply in all material respects with its
certificate of incorporation.

         4.       Waiver. Guarantor hereby waives and relinquishes all rights
and remedies accorded by applicable law to sureties or guarantors and agrees not
to assert or take advantage of any such rights or remedies, including without
limitation (a) any right to require CGC or any Facility Owner to proceed against
any of the Affiliated Parties or any other person or to proceed against or
exhaust any security held by CGC or any Facility Owner at any time or to pursue
any other remedy in CGC's or any Facility Owner's power before proceeding
against Guarantor, (b) any defense that may arise by reason of the incapacity,
lack of power or authority, death, dissolution, merger, termination or
disability of any of the Affiliated Parties or any other person or the failure
of CGC or any Facility Owner to file or enforce a claim against the estate (in

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administration, bankruptcy or any other proceeding) of any of the Affiliated
Parties or any other person, (c) demand, presentment, protest and notice of any
kind, including without limitation notice of the existence, creation or
incurring of any new or additional obligation or of any action or non-action on
the part of any of the Affiliated Parties or creditor of any of the Affiliated
Parties or Guarantor or on the part of any other person under this or any other
instrument in connection with any obligation or evidence of indebtedness held by
CGC and/or the facility Owners as collateral or in connection with any
Obligations, (d) any defense based upon an election of remedies by CGC or any
Facility Owner, including without limitation an election to proceed by
non-judicial rather than judicial foreclosure, which destroys or otherwise
impairs the subrogation rights of Guarantor, the right of Guarantor to proceed
against any of the Affiliated Parties for reimbursement, or both, (e) any
defense based on any offset against any amounts which may be owed by any person
to Guarantor for any reason whatsoever, (f) any defense based on any act,
failure to act, delay or omission whatsoever on the part of any of the
Affiliated Parties or the failure by any of the Affiliated Parties to do any act
or thing or to observe or perform any covenant, condition or agreement to be
observed or performed by it under the Relevant Documents, (g) any defense based
upon any statute or rule of law which provides that the obligation of a surety
must be neither larger in amount nor in other respects more burdensome than that
of the principal except that this Guaranty shall only cover the Obligations as
they may be amended from time to time and, that, upon payment in full of the
Obligations, this Guaranty shall no longer be of any force or effect, (h) any
defense, setoff or counterclaim which may at any time be available to or
asserted by any of the Affiliated Parties against CGC or any Facility Owner or
any other person under the Relevant Documents (other than defense of payment or
performance of the Guaranteed Obligations), (i) any duty on the part of CGC or
any Facility Owner to disclose to Guarantor any facts CGC or any Facility Owner
may now or hereafter know about any of the Affiliated Parties, regardless of
whether CGC or any Facility Owner has reason to believe that any such facts
materially increase the risk beyond that which Guarantor intends to assume, or
has reason to believe that such facts are unknown to Guarantor, or has a
reasonable opportunity to communicate such facts to Guarantor, since Guarantor
acknowledges that Guarantor is fully responsible for being and keeping informed
of the financial condition of any of the Affiliated Parties and of all
circumstances bearing on the risk of non-payment of any obligations and
liabilities hereby guaranteed, (j) the fact that Guarantor may at any time in
the future dispose of all or part of its direct or indirect interest in any of
the Affiliated Parties, (k) any defense based on any change in the time, manner
or place of any payment under, or in any other term of, the Relevant Documents
or any other amendment, renewal, extension, acceleration, compromise or waiver
of or any consent or departure from the terms of the Relevant Documents, (l) any
right to assert the bankruptcy or insolvency of CGC or any Facility Owner or any
other Person as a defense hereunder or as the basis for rescission hereof and
any defense arising because of the election of CGC or any Facility Owner, in any
proceeding instituted under the federal bankruptcy code, of the application of
Section 1111(b)(2) of the federal bankruptcy code, and (m) any defense based
upon any borrowing or grant of a security interest under Section 364 of the
federal bankruptcy code.

         5.       Subordination. Except as otherwise specifically provided in
this Guaranty, all existing and future indebtedness of any of the Affiliated
Parties to Guarantor (except to the extent such indebtedness is incurred in the
ordinary course of business and relates to costs of materials or services
provided pursuant to or consistent with the Relevant Documents) and the right of
Guarantor to withdraw any capital invested by Guarantor in any of the Affiliated
Parties,

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is hereby subordinated to all obligations and liabilities hereby guaranteed.
Without the prior written consent of CGC and the Facility Owners, such
subordinated indebtedness shall not be paid or withdrawn in whole or in part,
nor shall Guarantor accept any payment of or on account of any such indebtedness
or as a withdrawal of capital while this Guaranty is in effect if any Affiliated
Party is then in default under any of the Relevant Documents. Any payment by any
of the Affiliated Parties in violation of this Guaranty shall be received by
Guarantor in trust for CGC and the Facility Owners, and Guarantor shall cause
the same to be paid to CGC and/or the Facility Owners immediately upon demand by
CGC and/or the Facility Owners on account of the relevant Affiliated Parties'
obligations and liabilities hereby guaranteed. Guarantor shall not assign all or
any portion of such indebtedness while this Guaranty remains in effect except
upon prior written notice to CGC and the Facility Owners by which the assignee
of any such indebtedness agrees that the assignment is made subject to the terms
of this Guaranty, and that any attempted assignment of such indebtedness in
violation of the provisions hereof shall be void.

         6.       Subrogation. Until the Obligations have been paid in full, (a)
Guarantor shall not have any right of subrogation and waives all rights to
enforce any remedy which CGC and the Facility Owners now have or may hereafter
have against any of the Affiliated Parties, and waives the benefit of, and all
rights to participate in, any security now or hereafter held by CGC and the
Facility Owners from any of the Affiliated Parties and (b) Guarantor waives any
claim, right or remedy which Guarantor now has or hereafter acquires against any
of the Affiliated Parties that arises hereunder and/or from the performance by
the Guarantor hereunder including, without limitation, any claim, remedy or
right of subrogation, reimbursement, exoneration, contribution, indemnification,
or participation in any claim, right or remedy of CGC and the Facility Owners
against any of the Affiliated Parties, or any security which CGC and the
Facility Owners now has or may hereafter acquire, whether or not such claim,
right or remedy arises in equity, under contract, by statute, under common law
or otherwise.

         7.       Bankruptcy.

                  (a)      The obligations of Guarantor under this Guaranty
shall not be altered, limited or affected by any proceeding, voluntary or
involuntary, involving the bankruptcy, reorganization, insolvency, receivership,
liquidation or arrangement of any of the Affiliated Parties, or by any defense
which any of the Affiliated Parties may have by reason of any order, decree or
decision of any court or administrative body resulting from any such proceeding.

                  (b)      So long as any Obligations are owed to CGC and the
Facility Owners, to the extent of such Obligations, Guarantor shall file, in any
bankruptcy or other proceeding in which the filing of claims is required or
permitted by law, all claims which Guarantor may have against any of the
Affiliated Parties relating to any indebtedness of any of the Affiliated Parties
to Guarantor, and hereby assigns to CGC and the Facility Owners all rights of
Guarantor thereunder. If Guarantor does not file any such claim, CGC and the
Facility Owners are hereby authorized to do so in the name of Guarantor or, in
their discretion, to assign the claim to a nominee and to cause proofs of claim
to be filed in the name of their nominee. The foregoing power of attorney is
coupled with an interest and cannot be revoked. CGC and the Facility Owners or
their respective nominees shall have the sole right to accept or reject any plan
proposed in any such proceeding and to take any other action which a party
filing a claim is entitled to take. In all such cases, whether in
administration, bankruptcy or otherwise, the person

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authorized to pay such a claim shall pay the same to CGC and the Facility Owners
to the extent of any Obligations which then remain unpaid, and, to the full
extent necessary for that purpose, Guarantor hereby assigns to CGC and the
Facility Owners all of Guarantor's rights to all such payments or distributions
to which Guarantor would otherwise be entitled; provided, however, that
Guarantor's obligations hereunder shall not be satisfied except to the extent
that CGC and the Facility Owners receive cash by reason of any such payment or
distribution. If CGC and the Facility Owners receive anything hereunder other
than cash, the same shall be held as collateral for amounts due under this
Guaranty.

         8.       Successions or Assignments.

                  (a)      This Guaranty shall inure to the benefit of the
successors or assigns of CGC and the Facility Owners who shall have, to the
extent of its interest, the rights of CGC and the Facility Owners hereunder.

                  (b)      This Guaranty is binding upon Guarantor and its
successors and assigns. Guarantor is not entitled to assign its obligations
hereunder to any other person without the written consent of CGC and the
Facility Owners, and any purported assignment in violation of this provision
shall be void.

         9.       Waivers.

                  (a)      No delay on the part of CGC or any Facility Owner in
exercising any of its rights (including those hereunder) and no partial or
single exercise thereof and no action or non-action by CGC or any Facility
Owner, with or without notice to Guarantor or anyone else, shall constitute a
waiver of any rights or shall affect or impair this Guaranty.

                  (b)      GUARANTOR HEREBY WAIVES ITS RIGHT TO A JURY TRIAL OF
ANY CLAM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS GUARANTY OR
RELATING TO THE SUBJECT MATTER OF THIS GUARANTY AND THE RELATIONSHIP BETWEEN
GUARANTOR AND CGC AND THE FACILITY OWNERS THAT IS BEING ESTABLISHED. GUARANTOR
ACKNOWLEDGES THAT THIS WAIVER IS A MATERIAL INDUCEMENT TO ENTER INTO A BUSINESS
RELATIONSHIP, THAT COMPANY HAS RELIED ON THE WAIVER ACCEPTING THIS GUARANTY, AND
THAT CGC AND THE FACILITY OWNERS WILL CONTINUE TO RELY ON THE WAIVER IN THEIR
RELATED FUTURE DEALINGS. GUARANTOR FURTHER WARRANTS AND REPRESENTS THAT IT HAS
REVIEWED THIS WAIVER WITH ITS LEGAL COUNSEL, AND THAT IT KNOWINGLY AND
VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS FOLLOWING CONSULTATION WITH LEGAL
COUNSEL.

         10.      Interpretation. The section headings in this Guaranty are for
the convenience of reference only and shall not affect the meaning or
construction of any provision hereof.

         11.      Notices. All notices in connection with this Guaranty shall be
given by telex or cable or by notice in writing hand-delivered or sent by
facsimile transmission or by certified mail return-receipt requested (airmail,
if overseas), postage prepaid. All such notices shall be sent to the appropriate
telex or telecopier number or address, as the case may be, set forth in Section
15

<PAGE>

below or to such other number or address as shall have been subsequently
specified by written notice to the other party, and shall be sent with copies,
if any, as indicated below. All such notices shall be effective upon receipt,
and confirmation by answerback of any such notice so sent by telex shall be
sufficient evidence of receipt thereof.

         12.      Amendments. This Guaranty may be amended only with the written
consent of the parties hereto.

         13.      Jurisdiction; Governing Law.

                  (a)      Any action or proceeding relating in any way to this
Guaranty may be brought and enforced in the courts of the State of New York or
of the United States for the Southern District of New York. Any such process or
summons in connection with any such action or proceeding may be served by
mailing a copy thereof by certified or registered mail, or any substantially
similar form of mail, addressed to Guarantor as provided for notices hereunder.

                  (b)      This Guaranty and the rights and obligations of CGC,
the Facility Owners and the Guarantor shall be governed by and construed in
accordance with the law of the State of New York without reference to principles
of conflicts of laws (other than Section 5-1401 of the New York General
Obligations Law).

         14.      Integration of Terms. This Guaranty contains the entire
agreement between the Guarantor and CGC and the Facility Owners relating to the
subject matter hereof and supersedes all oral statements and prior writing with
respect hereto.

         15.      Addresses.

                  (a)      The address of Guarantor for notices is:

                                   Calpine Corporation
                                   50 West San Fernando Street
                                   San Jose, California 95113
                                   Attention: General Counsel
                                   Telephone Number: (408) 995-5115
                                   Telecopier Number: (408) 995-0505

                  (b)      The address of CGC for notices is:

                                   Calpine Generating Company, LLC
                                   c/o Calpine Corporation
                                   50 West San Fernando Street
                                   San Jose, California 95113
                                   Attention: General Counsel
                                   Telephone No.: (408) 995-5115
                                   Telecopy No.: (408) 995-0505

                  (c)      The addresses of the Facility Owners for notices are
                           set forth on Exhibit A attached hereto.

<PAGE>

         16.      Interest; Collection Expenses. Any amount required to be paid
by Guarantor pursuant to the terms hereof shall bear interest at the an annual
rate equal to the "prime rate" as published from time to time in the Wall Street
Journal, plus 2%, such rate to change when the "prime rate" changes, or the
maximum rate permitted by law, whichever is less, from the date due until paid
in full. If CGC or any Facility Owner is required to pursue any remedy against
Guarantor hereunder, Guarantor shall pay to CGC or such Facility Owner, as the
case may be, upon demand, all reasonable attorneys' fees and expenses, and all
other costs and expenses incurred by CGC or such Facility Owner in enforcing
this Guaranty.

         17.      Reinstatement of Guaranty. This Guaranty shall continue to be
effective or be reinstated, as the case may be, if at any time any payment to or
on behalf of any of the Affiliated Parties or to CGC and the Facility Owners by
any of the Affiliated Parties under the Relevant Documents or by Guarantor
hereunder is rescinded or must otherwise be returned by CGC or any Facility
Owner upon the insolvency, bankruptcy, reorganization, dissolution or
liquidation of any of the Affiliated Parties or otherwise, all as though such
payment had not been made.

         18.      Counterparts. The Guaranty may be executed in one or more
duplicate counterparts, and when executed and delivered by all of the parties
listed below shall constitute a single binding agreement.

                  IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to
be duly executed and delivered as of the day and year first written above.

                                     CALPINE CORPORATION,
                                     a Delaware corporation

                                     BY: /s/ Zamir Rauf
                                         ------------------------------
                                     Name:  ZAMIR RAUF
                                     Title: Vice President

Accepted and agreed.

CALPINE GENERATING COMPANY, LLC
         a Delaware limited liability company,
         for itself and for each of the Facility Owners

By: /s/ Zamir Rauf
    ----------------------
Name:  ZAMIR RAUF
Title: Vice President

<PAGE>

                                    EXHIBIT A

                             LIST OF FACILITY OWNERS

BAYTOWN ENERGY CENTER FACILITY

8605 FM 1405
Baytown, Texas 77520
(281) 303-4200

CARVILLE ENERGY CENTER FACILITY

4322 LA Highway 30
Saint Gabriel, Louisiana 70776
(225) 642-8993

CHANNEL ENERGY CENTER FACILITY

12000 Lawndale Street, LCR Gate 5
Pasadena, Texas 77017
(713)456-1300

COLUMBIA ENERGY CENTER

100 Calpine Way
Gaston, South Carolina 29053
(803) 739-4940

CORPUS CHRISTI ENERGY CENTER FACILITY

3852 Buddy Lawrence Drive
Corpus Christi, Texas 78407
(361) 696-7700

DECATUR ENERGY CENTER FACILITY

2024 Highway 20 West
Decatur, Alabama 35601
(256) 301-6500

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DELTA ENERGY CENTER FACILITY

1200 Darcy Lane
Pittsburg, California 94565
(925)756-0789

FREESTONE ENERGY CENTER FACILITY

1366 FM 488
Fairfield, Texas 75840
(903)389-1400

GOLDENDALE ENERGY CENTER

600 Industrial Park Way
Goldendale, Washington 98620
(509)773-0380

LOS MEDANOS ENERGY CENTER FACILITY

750 East Third Street
Pittsburg, California 94565
(925)473-2180

MORGAN ENERGY CENTER

1410 Red Hat Road
Decatur, Alabama 35601
(256)308-3300

ONETA ENERGY CENTER FACILITY

25142 East 105th Street South
Broken Arrow, Oklahoma 74014
(918)486-1800

PASTORIA ENERGY CENTER

39789 Edmonston Pumping Plant Road
Lebec, California 93243
(661)654-8000

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ZION ENERGY CENTER

5701 Ninth Street
Zion, Illinois 60099
(847)731-6250