<PAGE>

                                  EXHIBIT 4.15

                                     FORM OF

                               CALPINE CORPORATION

                               GUARANTEE AGREEMENT

                         CALPINE CAPITAL TRUST [IV] [V]

                           DATED AS OF _____ ___, ____


<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                Page
<S>     <C>                                                                     <C>
ARTICLE I                                                                         1
DEFINITIONS
        Section 1.01  Definitions                                                 1

ARTICLE II                                                                        4
TRUST INDENTURE ACT
        Section 2.01  Trust Indenture Act; Application                            4
        Section 2.02  Lists of Holders of Preferred Securities                    4
        Section 2.03  Reports by the Guarantee Trustee                            4
        Section 2.04  Periodic Reports to the Guarantee Trustee                   4
        Section 2.05  Evidence of Compliance with Conditions Precedent            5
        Section 2.06  Events of Default; Waiver                                   5
        Section 2.07  Disclosure of Information                                   5
        Section 2.08  Conflicting Interest                                        5

ARTICLE III                                                                       5
POWERS, DUTIES AND RIGHTS OF THE GUARANTEE TRUSTEE
        Section 3.01  Powers and Duties of the Guarantee Trustee                  5
        Section 3.02  Certain Rights and Duties of the Guarantee Trustee          6
        Section 3.03  Not Responsible for Recitals or Issuance of Guarantee       7
        Section 3.04  The Guarantee Trustee May Own Preferred Securities          7
        Section 3.05  Moneys Received by the Guarantee Trustee to Be
                      Held in Trust Without Interest.                             8
        Section 3.06  Compensation and Expenses of Guarantee Trustee              8

ARTICLE IV                                                                        8
GUARANTEE TRUSTEE
        Section 4.01  Qualifications                                              8
        Section 4.02  Appointment, Removal and Resignation of the
                      Guarantee Trustee                                           9

ARTICLE V                                                                         9
GUARANTEE

        Section 5.01  Guarantee                                                   9
        Section 5.02  Waiver of Notice                                            9
        Section 5.03  Obligations Not Affected                                    9
        Section 5.04  Enforcement of Guarantee                                   10
        Section 5.05  Guarantee of Payment                                       10
        Section 5.06  Subrogation                                                11
        Section 5.07  Independent Obligations                                    11

ARTICLE VI                                                                       11
LIMITATION OF TRANSACTIONS; SUBORDINATION
        Section 6.01  Limitation of Transactions                                 11
       [Section 6.02  Subordination]                                             11

ARTICLE VII                                                                      11
TERMINATION
        Section 7.01  Termination                                                11

ARTICLE VIII
LIMITATION OF LIABILITY; INDEMNIFICATION
        Section 8.01  Exculpation                                                12
        Section 8.02  Indemnification                                            12
        Section 8.03  Survive Termination                                        12

ARTICLE IX                                                                       12
MISCELLANEOUS
        Section 9.01  Successors and Assigns                                     12
        Section 9.02  Amendments                                                 13
</TABLE>

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<TABLE>
<S>     <C>                                                                     <C>
        Section 9.03  Notices                                                   13
        Section 9.04  Genders                                                   13
        Section 9.05  Benefit.                                                  14
        Section 9.06  Governing Law                                             14
        Section 9.07  Counterparts                                              14
       [Section 9.08  Exercise of Overallotment Option]                         14
        Section 9.09  Limited Liability                                         14
</TABLE>

<PAGE>

                               GUARANTEE AGREEMENT

This GUARANTEE AGREEMENT, dated as of __________, ____, is executed and
delivered by CALPINE CORPORATION, a Delaware corporation (the "Guarantor"), and
Wilmington Trust Company, a Delaware banking corporation, as the initial
Guarantee Trustee (as defined herein) for the benefit of the Holders (as defined
herein) from time to time of the Preferred Securities (as defined herein) of
Calpine Capital Trust [IV] [V], a Delaware statutory business trust (the
"Issuer").

WHEREAS, pursuant to the Amended and Restated Declaration of Trust (the
"Declaration"), dated as of ______________, ____ among the trustees of the
Issuer named therein, Calpine Corporation, as Depositor, and the Holders from
time to time of preferred undivided beneficial interests in the assets of the
Issuer, the Issuer may issue up to $_____________ aggregate liquidation amount
of its _____% Trust Preferred Securities (the "Preferred Securities")
representing preferred undivided beneficial interests in the assets of the
Issuer and having the terms set forth in the Declaration [, of which
$_____________ liquidation amount of Preferred Securities is being issued as of
the date hereof. Up to the remaining $______________ liquidation amount of
Preferred Securities may be issued by the Issuer if and to the extent that the
over-allotment option granted by the Guarantor and the Issuer pursuant to the
Underwriting Agreement (as may be defined in the Declaration) is exercised by
the Underwriters named in the Underwriting Agreement]; and

WHEREAS, as incentive for the Holders to purchase Preferred Securities, the
Guarantor desires to irrevocably and unconditionally agree, to the extent set
forth herein, to pay to the Holders the Guarantee Payments (as defined herein)
and to make certain other payments on the terms and conditions set forth herein;

NOW, THEREFORE, in consideration of the purchase by the initial purchasers
thereof of Preferred Securities, which purchase the Guarantor hereby agrees
shall benefit the Guarantor, the Guarantor executes and delivers this Guarantee
Agreement for the benefit of the Holders from time to time.

                                    ARTICLE I
                                   DEFINITIONS

Section 1.01 Definitions.

(a) Capitalized terms used in this Guarantee Agreement but not defined in the
preamble or recitals above have the respective meanings assigned to them in this
Section 1.01.

(b) A term defined anywhere in this Guarantee Agreement has the same meaning
throughout.

(c) All references to the Guarantee Agreement or this Guarantee Agreement are to
this Guarantee Agreement as modified, supplemented or amended from time to time.

(d) All references in this Guarantee Agreement to Articles and Sections are to
Articles and Sections of this Guarantee Agreement unless otherwise specified.

(e) A term defined in the Trust Indenture Act has the same meaning when used in
this Guarantee Agreement unless otherwise defined in this Guarantee Agreement or
unless the context otherwise requires.

(f) A reference to the singular includes the plural and vice versa. Additional
Amounts has the meaning set forth in the Indenture.

"Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by, or under direct or indirect common
control with, such specified Person. For purposes of this definition, control of
a Person shall mean the power to direct the management and policies of such
Person, directly or indirectly, whether through the ownership of voting
securities, by contract or otherwise, and the terms controlling and controlled
shall have meanings correlative to the foregoing.


                                       1
<PAGE>

"Business Day" has the meaning set forth in the Indenture.

"Commission" means the Securities and Exchange Commission.

"Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer and having the terms set forth
in Exhibit [__] to the Declaration.

"Common Stock" means the common stock, $_____ par value per share, of the
Guarantor, including associated preferred share purchase rights.

"Debentures" means the series of [convertible] unsecured [junior subordinated]
[senior] debentures issued to the [Property Trustee] [Trust] by [Calpine
Corporation] under the Indenture and entitled the ___% [Convertible] [Junior
Subordinated] [Senior] Debentures due _____.

"Declaration" has the meaning set forth in the recitals above.

"Distributions" means the periodic distributions and other payments payable to
Holders in accordance with the terms of the Preferred Securities set forth in
Exhibit [__] to the Declaration.

"Event of Default" means a default by the Guarantor on any of its payment or
other obligations under this Guarantee Agreement; provided, however, that,
except with respect to a default in payment of any Guarantee Payment, any such
default shall constitute an Event of Default only if the Guarantor shall have
received notice of such default and shall not have cured such default within 60
days after receipt of such notice.

"Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Preferred Securities, to the extent not paid or
made by or on behalf of the Issuer: (i) any accumulated and unpaid
Distributions, any Additional Amounts payable with respect to the Preferred
Securities in accordance with the terms thereof and the Redemption Price,
including all accumulated and unpaid Distributions and Additional Amounts to the
date of redemption, with respect to the Preferred Securities called for
redemption by the Issuer but only if and to the extent that in each case the
Guarantor has made a payment to the Property Trustee of principal of, any
premium or interest on or any Additional Amounts with respect to the Debentures
and (ii) upon a voluntary or involuntary dissolution of the Issuer (other than
in connection with the distribution of Debentures to Holders in exchange for
Preferred Securities or the redemption of the Preferred Securities in full upon
the maturity or redemption of the Debentures as provided in the Declaration),
the lesser of (a) the aggregate of the liquidation amount and all accumulated
and unpaid Distributions and Additional Amounts on the Preferred Securities to
the date of payment, to the extent the Issuer has funds on hand legally
available therefor, and (b) the amount of assets of the Issuer remaining
available for distribution to Holders in liquidation of the Issuer as required
by applicable law.

"Guarantee Trustee" means Wilmington Trust Company, a Delaware banking
corporation, in its capacity as guarantee trustee hereunder, until a Successor
Guarantee Trustee has been appointed and has accepted such appointment pursuant
to the terms of this Guarantee Agreement, and thereafter means each such
Successor Guarantee Trustee, in its capacity as guarantee trustee hereunder.

"Holder" means any holder, as registered on the books and records of the Issuer,
of any Preferred Securities; provided, however, that in determining whether the
holders of the requisite percentage of Preferred Securities have given any
request, notice, consent or waiver hereunder, Holder shall not include the
Guarantor or any Affiliate of the Guarantor.

"Indemnified Person" means the Guarantee Trustee, any Affiliate of the Guarantee
Trustee, and any officers, directors, shareholders, members, partners,
employees, representatives or agents of the Guarantee Trustee.

"Indenture" means the Indenture dated as of [August 10, 2000 between Calpine
Corporation and Wilmington Trust Company, as trustee, [as supplemented by the
________ Supplemental Indenture thereto


                                       2
<PAGE>

dated as of _______ __, ____ (the Supplemental Indenture)]], pursuant to which
the Debentures are to be issued to the [Property Trustee] [Trust].

"Majority of Outstanding Preferred Securities" means Holder(s) of outstanding
Preferred Securities, voting together as a single class, who are the record
owners of Preferred Securities representing a majority of the outstanding
Preferred Securities.

"Officers' Certificate" means, with respect to any Person, a certificate signed
by the Chairman of the Board, the President, any Vice Chairman of the Board, any
Vice President, the chief financial officer, the Treasurer, any Assistant
Treasurer, the Controller, the Secretary or any Assistant Secretary of such
Person, and delivered to the Guarantee Trustee. One of the officers signing an
Officers' Certificate given pursuant to Section 2.04 shall be the principal
executive, financial or accounting officer of the Guarantor. Any Officers'
Certificate delivered with respect to compliance with a condition or covenant
provided for in this Guarantee Agreement (other than pursuant to Section
314(a)(4) of the Trust Indenture Act) shall include:

(i) a statement that the person making such certificate has read such covenant
or condition;

(ii) a brief statement as to the nature and scope of the examination or
investigation upon which the statements or opinions contained in such
certificate are based;

(iii) a statement that, in the opinion of such person, he has made such
examination or investigation as is necessary to enable him to express an
informed opinion as to whether or not such covenant or condition has been
complied with; and

(iv) a statement as to whether or not, in the opinion of such person, such
condition or covenant has been complied with.

"Person" means any individual, corporation, partnership, limited liability
company, joint venture, incorporated or unincorporated association, joint stock
company, trust, unincorporated organization or government or other agency or
political subdivision thereof or other entity of any kind.

"Preferred Securities" has the meaning set forth in the recitals above.

"Property Trustee" means the Person acting as Property Trustee under the
Declaration.

"Redemption Price" means the amount payable on redemption of the Preferred
Securities in accordance with the terms of the Preferred Securities.

"Responsible Officer" means, when used with respect to the Guarantee Trustee,
any officer within the corporate trust department of the Guarantee Trustee,
including any vice president, assistant vice president, assistant secretary,
assistant treasurer, trust officer or any other officer of the Guarantee Trustee
who customarily performs functions similar to those performed by the Persons who
at the time shall be such officers, respectively, or to whom any corporate trust
matter is referred because of such Person's knowledge of and familiarity with
the particular subject and, in either case, who shall have direct responsibility
for the administration of this Guarantee Agreement.

"Successor Guarantee Trustee" means a successor Guarantee Trustee possessing the
qualifications to act as a Guarantee Trustee under Section 4.01.

["Supplemental Indenture" has the meaning specified in the definition of
Indenture.]

"Trust Indenture Act" means the Trust Indenture Act of 1939, as amended.


                                       3
<PAGE>

                                   ARTICLE II
                               TRUST INDENTURE ACT

Section 2.01 Trust Indenture Act; Application.

(a) This Guarantee Agreement is subject to the provisions of the Trust Indenture
Act that are required to be part of this Guarantee Agreement and shall, to the
extent applicable, be governed by such provisions.

(b) If and to the extent that any provision of this Guarantee Agreement limits,
qualifies or conflicts with the duties imposed by Sections 310 to 317,
inclusive, of the Trust Indenture Act, such imposed duties shall control.

(c) The application of the Trust Indenture Act to this Guarantee Agreement shall
not affect the nature of the Preferred Securities as equity securities
representing preferred undivided beneficial interests in the assets of the
Issuer.

Section 2.02 Lists of Holders of Preferred Securities.

(a) The Guarantor shall provide the Guarantee Trustee (unless the Guarantee
Trustee is the registrar of the Preferred Securities) (i) within 14 days after
each record date for payment of Distributions, a list, in such form as the
Guarantee Trustee may reasonably require, of the names and addresses of the
Holders (List of Holders) as of such date, and (ii) at any other time, within 30
days of receipt by the Guarantor of a written request for a List of Holders as
of a date no more than 15 days before such List of Holders is given to the
Guarantee Trustee; provided that in each case the Guarantor shall not be
obligated to provide such List of Holders at any time that the List of Holders
does not differ from the most recent List of Holders given to the Guarantee
Trustee by the Guarantor. The Guarantee Trustee shall preserve, in as current a
form as is reasonably practicable, all information contained in the Lists of
Holders given to it; provided that the Guarantee Trustee may destroy any List of
Holders previously given to it on receipt of a new List of Holders.

(b) The Guarantee Trustee shall comply with its obligations under Section 312(b)
of the Trust Indenture Act.

Section 2.03 Reports by the Guarantee Trustee.

Within 60 days after ______ of each year, commencing _______, ____, the
Guarantee Trustee shall deliver to the Holders such reports as are required by
Section 313(a) of the Trust Indenture Act, if any, in the form, in the manner
and at the times provided by Section 313 of the Trust Indenture Act. The
Guarantee Trustee shall also comply with the other requirements of Section 313
of the Trust Indenture Act. A copy of each such report shall, at the time of
such transmission to the Holders, be filed by the Guarantee Trustee with the
Guarantor, with each stock exchange or quotation system upon which any Preferred
Securities are listed or traded (if so listed or traded) and also with the
Commission. The Guarantor agrees to notify the Guarantee Trustee when any
Preferred Securities become listed on any stock exchange or quotation system and
of any delisting thereof.

Section 2.04 Periodic Reports to the Guarantee Trustee.

The Guarantor shall provide to the Guarantee Trustee, the Commission and the
Holders, as applicable, such documents, reports and information (if any) as
required by Section 314(a)(1)-(3) of the Trust Indenture Act and the compliance
certificates required by Section 314(a)(4) and (c) of the Trust Indenture Act,
any such certificates to be provided in the form, in the manner and at the times
required by Section 314(a)(4) and (c) of the Trust Indenture Act (provided that
any certificate to be provided pursuant to Section 314(a)(4) of the Trust
Indenture Act shall be provided within 120 days of the end of each fiscal year
of the Issuer). Delivery of such reports, information and documents to the
Guarantee Trustee is for informational purposes only and the Guarantee Trustee's
receipt of such shall not constitute constructive notice of any information
contained therein, including the Guarantor's compliance with any of its
covenants hereunder (as to which the


                                       4
<PAGE>

Guarantee Trustee is entitled to rely exclusively on Officers' Certificates or
on certificates provided pursuant to this Section 2.04).

Section 2.05 Evidence of Compliance with Conditions Precedent.

The Guarantor shall provide to the Guarantee Trustee such evidence of compliance
with any conditions precedent, if any, provided for in this Guarantee Agreement
which relate to any of the matters set forth in Section 314(c) of the Trust
Indenture Act. Any certificate or opinion required to be given by an officer
pursuant to Section 314(c) may be given in the form of an Officers' Certificate.

Section 2.06 Events of Default; Waiver.

(a) The Holders of a Majority of Outstanding Preferred Securities may, by vote,
on behalf of the Holders, waive any past Event of Default and its consequences.
Upon such waiver, any such Event of Default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured, for every
purpose of this Guarantee Agreement, but no such waiver shall extend to any
subsequent or other default or Event of Default, or impair any right consequent
thereon.

(b) The right of any Holder to receive payment of the Guarantee Payments in
accordance with this Guarantee Agreement, or to institute suit for the
enforcement of any such payment, shall not be impaired without the consent of
each such Holder.

Section 2.07 Disclosure of Information.

The disclosure of information as to the names and addresses of the Holders in
accordance with Section 312 of the Trust Indenture Act, regardless of the source
from which such information was derived, shall not be deemed to be a violation
of any existing law, or any law hereafter enacted which does not specifically
refer to Section 312 of the Trust Indenture Act, nor shall the Guarantee Trustee
be held accountable by reason of mailing any material pursuant to a request made
under Section 312(b) of the Trust Indenture Act.

Section 2.08 Conflicting Interest.

(a) The Declaration and the Indenture shall be deemed to be specifically
described in this Guarantee Agreement for the purposes of clause (i) of the
first proviso contained in Section 310(b) of the Trust Indenture Act.

(b) The Guarantee Trustee shall comply with its obligations under Sections
310(b) and 311 of the Trust Indenture Act.

                                   ARTICLE III
                            POWERS, DUTIES AND RIGHTS
                            OF THE GUARANTEE TRUSTEE

Section 3.01 Powers and Duties of the Guarantee Trustee.

(a) This Guarantee Agreement shall be held by the Guarantee Trustee in trust for
the benefit of the Holders. The Guarantee Trustee shall not transfer its right,
title and interest in this Guarantee Agreement to any Person except a Successor
Guarantee Trustee on acceptance by such Successor Guarantee Trustee of its
appointment to act as Guarantee Trustee or to a Holder exercising his or her
rights pursuant to Section 5.04(iv). The right, title and interest of the
Guarantee Trustee to this Guarantee Agreement shall vest automatically in each
Person who may hereafter be appointed as Guarantee Trustee in accordance with
Article IV. Such vesting and cessation of title shall be effective whether or
not conveyancing documents have been executed and delivered.

(b) If an Event of Default has occurred and is continuing, the Guarantee Trustee
shall be entitled to enforce this Guarantee Agreement for the benefit of the
Holders.


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<PAGE>

(c) This Guarantee Agreement and all moneys received by the Guarantee Trustee in
respect of the Guarantee Payments will not be subject to any right, charge,
security interest, lien or claim of any kind in favor of, or for the benefit of,
the Guarantee Trustee or its agents or their creditors.

(d) The Guarantee Trustee shall, within 90 days after the occurrence of an Event
of Default actually known to a Responsible Officer of the Guarantee Trustee,
transmit by mail, first class postage prepaid, to the Holders, as their names
and addresses appear upon the List of Holders, notice of all such Events of
Default, unless such defaults shall have been cured before the giving of such
notice; provided that the Guarantee Trustee shall be protected in withholding
such notice if and so long as the board of directors, the executive committee or
a trust committee of directors and/or Responsible Officers of the Guarantee
Trustee in good faith determines that the withholding of such notice is in the
interests of the Holders. The Guarantee Trustee shall not be deemed to have
knowledge of any Event of Default except any Event of Default as to which the
Guarantee Trustee shall have received written notice or unless a Responsible
Officer charged with the administration of this Guarantee Agreement shall have
obtained written notice of such Event of Default.

(e) The Guarantee Trustee shall continue to serve as a trustee until a Successor
Guarantee Trustee has been appointed and accepted that appointment in accordance
with Article IV.

Section 3.02 Certain Rights and Duties of the Guarantee Trustee.

(a) The Guarantee Trustee, before the occurrence of an Event of Default and
after the curing or waiving of all Events of Default that may have occurred,
shall undertake to perform only such duties as are specifically set forth in
this Guarantee Agreement, and no implied covenants shall be read into this
Guarantee Agreement against the Guarantee Trustee. In case an Event of Default
has occurred (that has not been cured or waived pursuant to Section 2.06), the
Guarantee Trustee shall exercise such of the rights and powers vested in it by
this Guarantee Agreement, and use the same degree of care and skill in its
exercise thereof, as a prudent person would exercise or use under the
circumstances in the conduct of his own affairs.

(b) No provision of this Guarantee Agreement shall be construed to relieve the
Guarantee Trustee from liability for its own negligent action, its own negligent
failure to act or its own willful misconduct, except that:

(i) prior to the occurrence of an Event of Default and after the curing or
waiving of all such Events of Default that may have occurred:

(A) the duties and obligations of the Guarantee Trustee shall be determined
solely by the express provisions of this Guarantee Agreement, and the Guarantee
Trustee shall not be liable except for the performance of such duties and
obligations as are specifically set forth in this Guarantee Agreement, and no
implied covenants or obligations shall be read into this Guarantee Agreement
against the Guarantee Trustee; and

(B) in the absence of bad faith on the part of the Guarantee Trustee, the
Guarantee Trustee may conclusively rely, as to the truth of the statements and
the correctness of the opinions expressed therein, upon any certificates or
opinions furnished to the Guarantee Trustee and conforming to the requirements
of this Guarantee Agreement; provided, however, that in the case of any such
certificates or opinions that by any provision hereof or the Trust Indenture Act
are specifically required to be furnished to the Guarantee Trustee, the
Guarantee Trustee shall be under a duty to examine the same to determine whether
or not they conform to the requirements of this Guarantee Agreement or the Trust
Indenture Act, as the case may be;

(ii) the Guarantee Trustee shall not be liable for any error of judgment made in
good faith by a Responsible Officer of the Guarantee Trustee, unless it shall be
proved that the Guarantee Trustee was negligent in ascertaining the pertinent
facts upon which such judgment was made;

(iii) the Guarantee Trustee shall not be liable with respect to any action taken
or omitted to be taken by it in


                                       6
<PAGE>

good faith in accordance with the direction of the Holders of a Majority of
Outstanding Preferred Securities relating to the time, method and place of
conducting any proceeding for any remedy available to the Guarantee Trustee, or
exercising any trust or power conferred upon the Guarantee Trustee under this
Guarantee Agreement; and

(iv) no provision of this Guarantee Agreement shall require the Guarantee
Trustee to expend or risk its own funds or otherwise incur personal financial
liability in the performance of any of its duties or in the exercise of any of
its rights or powers, if it shall have reasonable grounds for believing that the
repayment of such funds or liability is not reasonably assured to it under the
terms of this Guarantee Agreement or adequate indemnity against such risk or
liability is not reasonably assured to it.

(c) Subject to the provisions of Section 3.02(a) and (b):

(i) whenever in the administration of this Guarantee Agreement, the Guarantee
Trustee shall deem it desirable that a matter be proved or established prior to
taking, suffering or omitting any action hereunder, the Guarantee Trustee
(unless other evidence is herein specifically prescribed) may, in the absence of
bad faith on its part, request and rely upon an Officers' Certificate, which,
upon receipt of such request, shall be promptly delivered by the Guarantor;

(ii) the Guarantee Trustee (A) may consult with counsel (which may be counsel to
the Guarantor or any of its Affiliates and may include any of its employees)
selected by it in good faith and with due care and the written advice or opinion
of such counsel with respect to legal matters shall be full and complete
authorization and protection in respect of any action taken, suffered or omitted
by it hereunder in good faith and in reliance thereon and in accordance with
such advice and opinion and (B) shall have the right at any time to seek
instructions concerning the administration of this Guarantee Agreement from any
court of competent jurisdiction;

(iii) the Guarantee Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents or
attorneys, and the Guarantee Trustee shall not be responsible for any misconduct
or negligence on the part of any agent or attorney appointed by it in good faith
and with due care;

(iv) the Guarantee Trustee shall be under no obligation to exercise any of the
rights or powers vested in it by this Guarantee Agreement at the request or
direction of any Holder, unless such Holder shall have offered to the Guarantee
Trustee security and indemnity satisfactory to the Guarantee Trustee against the
costs, expenses (including attorneys' fees and expenses) and liabilities that
might be incurred by it in complying with such request or direction; provided
that nothing contained in this clause (iv) shall relieve the Guarantee Trustee
of the obligation, upon the occurrence of an Event of Default (which has not
been cured or waived) to exercise such of the rights and powers vested in it by
this Guarantee Agreement, and to use the same degree of care and skill in this
exercise as a prudent person would exercise or use under the circumstances in
the conduct of his own affairs; and

(v) any action taken by the Guarantee Trustee or its agents hereunder shall bind
the Holders, and the signature of the Guarantee Trustee or its agents alone
shall be sufficient and effective to perform any such action; and no third party
shall be required to inquire as to the authority of the Guarantee Trustee to so
act, or as to its compliance with any of the terms and provisions of this
Guarantee Agreement, both of which shall be conclusively evidenced by the
Guarantee Trustee's or its agent's taking such action.

(vi) the Guarantee Trustee may conclusively rely, and shall be fully protected
in acting or refraining from acting upon, any resolution, certificate,
statement, instrument, opinion, report, notice, request, direction, consent,
order, bond, debenture, note, other evidence of indebtedness or other paper or
document believed by it to be genuine and to have been signed, sent or presented
by the proper party or parties;

(vii) any direction or act of the Guarantor contemplated by this Guarantee shall
be sufficiently evidenced by an Officer's Certificate;


                                       7
<PAGE>

(viii) the Guarantee Trustee shall not be bound to make any investigation into
the facts or matters stated in any resolution, certificate, statement,
instrument, opinion, report, notice, request, direction, consent, order, bond,
debenture, note, other evidence of indebtedness or other paper or document, but
the Guarantee Trustee, in its discretion, may make such further inquiry or
investigation into such facts or matters as it may see fit;

(ix) the Guarantee Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents, nominees,
custodians or attorneys, and the Guarantee Trustee shall not be responsible for
any misconduct or negligence on the part of any agent or attorney appointed with
due care by it hereunder;

(x) whenever in the administration of this Guarantee, the Guarantee Trustee
shall deem it desirable to receive instructions with respect to enforcing any
remedy or right or taking any other action hereunder, the Guarantee Trustee (A)
may request written instructions from the Holders of a Majority of Outstanding
Preferred Securities, (B) may refrain from enforcing such remedy or right or
taking such other action until such written instructions are received and (C)
shall be protected in conclusively relying on or acting in accordance with such
written instructions.

(d) no provision of this Guarantee shall be deemed to impose any duty or
obligation on the Guarantee Trustee to perform any act or acts or exercise any
right, power, duty or obligation conferred or imposed on it in any jurisdiction
in which it shall be illegal, or in which the Guarantee Trustee shall be
unqualified or incompetent to act in accordance with applicable law, to perform
any such act or acts or to exercise any such right, power, duty or obligation.
No permissive power or authority available to the Guarantee Trustee shall be
construed to be a duty.

Section 3.03 Not Responsible for Recitals or Issuance of Guarantee.

The recitals contained in this Guarantee Agreement shall be taken as the
statements of the Guarantor, and the Guarantee Trustee does not assume any
responsibility for their correctness. The Guarantee Trustee makes no
representations as to the validity or sufficiency of this Guarantee Agreement.

Section 3.04 The Guarantee Trustee May Own Preferred Securities.

The Guarantee Trustee, in its individual or any other capacity, may become the
owner or pledgee of Preferred Securities and may otherwise deal with the
Guarantor with the same rights it would have if it were not the Guarantee
Trustee.

Section 3.05 Moneys Received by the Guarantee Trustee to Be Held in Trust
Without Interest.

All moneys received by the Guarantee Trustee in respect of Guarantee Payments
shall, until used or applied as herein provided, be held in trust for the
purposes for which they were received, but need not be segregated from other
funds except to the extent required by law. The Guarantee Trustee shall be under
no liability for interest on any moneys received by it hereunder except such as
it may agree in writing to pay thereon.

Section 3.06 Compensation and Expenses of Guarantee Trustee.

The Guarantor covenants and agrees to pay to the Guarantee Trustee from time to
time, and the Guarantee Trustee shall be entitled to, such compensation as the
Guarantor and the Guarantee Trustee shall from time to time agree in writing
(which shall not be limited by any provision of law in regard to the
compensation of a Guarantee Trustee of an express trust) for all services
rendered by it in the exercise and performance of any of the powers and duties
hereunder of the Guarantee Trustee, and the Guarantor will pay or reimburse the
Guarantee Trustee upon its request for all reasonable expenses, disbursements
and advances incurred or made by the Guarantee Trustee in accordance with any of
the provisions of this Guarantee Agreement (including the reasonable
compensation and the reasonable expenses and disbursements of its counsel and of
all persons not regularly in its employ) except any such expense, disbursement
or advance as may arise


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<PAGE>

from its negligence or bad faith. The Guarantor also covenants to indemnify each
of the Guarantee Trustee or any predecessor Guarantee Trustee and their
officers, agents, directors and employees for, and to hold them harmless
against, any and all loss, liability, damage, claim or expense including taxes
(other than taxes based upon, measured by or determined by the income, profit,
franchise or doing business of the Guarantee Trustee) incurred without
negligence or bad faith on the part of the Guarantee Trustee and arising out of
or in connection with the acceptance or administration of this trust, including
the reasonable costs and expenses of defending itself against any claim (whether
asserted by the Guarantor, any Holder or any other Person) of liability in the
premises. The provisions of this Section 3.06 shall survive the termination of
this Guarantee Agreement and resignation or removal of the Guarantee Trustee.

                                   ARTICLE IV
                                GUARANTEE TRUSTEE

Section 4.01 Qualifications.

There shall at all times be a Guarantee Trustee that shall:

(i) not be an Affiliate of the Guarantor; and

(ii) be a national banking association or corporation organized and doing
business under the laws of the United States of America or any State or
Territory thereof or of the District of Columbia, or a corporation or Person
permitted by the Commission to act as an institutional trustee under the Trust
Indenture Act, authorized under such laws to exercise corporate trust powers,
having a combined capital and surplus of at least $50,000,000, and subject to
supervision or examination by Federal, State, Territorial or District of
Columbia authority. If such corporation publishes reports of condition at least
annually, pursuant to law or to the requirements of the supervising or examining
authority referred to above, then for the purposes of this clause (ii), the
combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so published.

If at any time the Guarantee Trustee shall cease to satisfy the requirements of
clauses (i) and (ii) above, the Guarantee Trustee shall immediately resign in
the manner and with the effect set out in Section 4.02. If the Guarantee Trustee
has or shall acquire any conflicting interest within the meaning of Section
310(b) of the Trust Indenture Act, the Guarantee Trustee and the Guarantor shall
in all respects comply with the provisions of Section 310(b) of the Trust
Indenture Act, subject to the penultimate paragraph thereof.

Section 4.02 Appointment, Removal and Resignation of the Guarantee Trustee.

(a) Subject to Section 4.02(b), in the absence of the existence of an Event of
Default, the Guarantee Trustee may be appointed or removed without cause at any
time by the Guarantor.

(b) The Guarantee Trustee shall not be removed in accordance with Section
4.02(a) until a Successor Guarantee Trustee possessing the qualifications to act
as Guarantee Trustee under Section 4.01 has been appointed and has accepted such
appointment by written instrument executed by such Successor Guarantee Trustee
and delivered to the Guarantor and the Guarantee Trustee being removed.

(c) The Guarantee Trustee appointed to office shall hold office until its
successor shall have been appointed or until its removal or resignation.

(d) The Guarantee Trustee may resign from office (without need for prior or
subsequent accounting) by an instrument (a "Resignation Request") in writing
signed by the Guarantee Trustee and delivered to the Guarantor, which
resignation shall take effect upon such delivery or upon such later date as is
specified therein; provided, however, that no such resignation of the Guarantee
Trustee shall be effective until a Successor Guarantee Trustee possessing the
qualifications to act as Guarantee Trustee under Section 4.01 has been appointed
and has accepted such appointment by instrument executed by such Successor
Guarantee Trustee and delivered to the Guarantor and the resigning Guarantee
Trustee.


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<PAGE>

(e) If no Successor Guarantee Trustee shall have been appointed and accepted
appointment as provided in this Section 4.02 within 30 days after delivery to
the Guarantor of a Resignation Request, the resigning Guarantee Trustee may
petition any court of competent jurisdiction for appointment of a Successor
Guarantee Trustee. Such court may thereupon after such notice, if any, as it may
deem proper, appoint a Successor Guarantee Trustee.

                                    ARTICLE V
                                    GUARANTEE

Section 5.01 Guarantee.

The Guarantor irrevocably and unconditionally agrees to pay in full to the
Holders the Guarantee Payments (without duplication of amounts theretofore paid
by the Issuer), as and when due, regardless of any defense, right of set- off or
counterclaim which the Issuer may have or assert. The Guarantor's obligation to
make a Guarantee Payment may be satisfied by direct payment of the required
amounts by the Guarantor to the Holders or to the Guarantee Trustee for
remittance to the Holders or by causing the Issuer to pay such amounts to the
Holders. The Guarantor shall give written notice to the Guarantee Trustee as
promptly as practicable in the event it makes any direct payment hereunder.

Section 5.02 Waiver of Notice.

The Guarantor hereby waives notice of acceptance of this Guarantee Agreement and
of any liability to which it applies or may apply, presentment, demand for
payment, any right to require a proceeding first against the Issuer or any other
Person before proceeding against the Guarantor, protest, notice of nonpayment,
notice of dishonor, notice of redemption and all other notices and demands.
Notwithstanding anything to the contrary herein, the Guarantor retains all of
its rights under the Indenture to extend the interest payment period on the
Debentures and the Guarantor shall not be obligated hereunder to make any
Guarantee Payment during any Extended Interest Payment Period (as defined in the
Supplemental Indenture) with respect to the Distributions on the Preferred
Securities.

Section 5.03 Obligations Not Affected.

The obligations, covenants, agreements and duties of the Guarantor under this
Guarantee Agreement shall in no way be affected or impaired by reason of the
happening from time to time of any of the following:

(a) the release or waiver, by operation of law or otherwise, of the performance
or observance by the Issuer of any express or implied agreement, covenant, term
or condition relating to the Preferred Securities to be performed or observed by
the Issuer;

(b) the extension of time for the payment by the Issuer of all or any portion of
the Distributions (other than an extension of time for payment of Distributions
that result from any Extended Interest Payment Period), Redemption Price,
Liquidation Distribution (as may be defined in the Declaration) or any other
sums payable under the terms of the Preferred Securities or the extension of
time for the performance of any other obligation under, arising out of, or in
connection with, the Preferred Securities (other than an extension of time for
payment of Distributions that result from any Extended Interest Payment Period);

(c) any failure, omission, delay or lack of diligence on the part of the
Guarantee Trustee or the Holders to enforce, assert or exercise any right,
privilege, power or remedy conferred on the Guarantee Trustee or the Holders
pursuant to the terms hereof or of the Preferred Securities, respectively, or
any action on the part of the Issuer granting indulgence or extension of any
kind;

(d) the voluntary or involuntary liquidation, dissolution, sale of any
collateral, receivership, insolvency, bankruptcy, assignment for the benefit of
creditors, reorganization, arrangement, composition or readjustment of debt of,
or other similar proceedings affecting, the Issuer or any of the assets of the
Issuer;

(e) any invalidity of, or defect or deficiency in, the Preferred Securities;


                                       10
<PAGE>

(f) the settlement or compromise of any obligation guaranteed hereby or hereby
incurred; or

(g) any other circumstance whatsoever that might otherwise constitute a legal or
equitable discharge or defense of a guarantor, it being the intent of this
Section 5.03 that the obligations of the Guarantor with respect to the Guarantee
Payments shall be absolute and unconditional under any and all circumstances.

There shall be no obligation of the Guarantee Trustee or the Holders to give
notice to, or obtain consent of, the Guarantor with respect to the happening of
any of the foregoing.

Section 5.04 Enforcement of Guarantee.

The Guarantor and the Guarantee Trustee expressly acknowledge and agree that (i)
this Guarantee Agreement will be deposited with the Guarantee Trustee to be held
for the benefit of the Holders; (ii) the Guarantee Trustee has the right to
enforce this Guarantee Agreement on behalf of the Holders; (iii) Holders
representing not less than a Majority of Outstanding Preferred Securities have
the right to direct the time, method and place of conducting any proceeding for
any remedy available to the Guarantee Trustee in respect of this Guarantee
Agreement or exercising any trust or other power conferred upon the Guarantee
Trustee under this Guarantee Agreement provided, that, subject to Section 3.1,
the Guarantee Trustee shall have the right to decline to follow any such
direction if the Guarantee Trustee being advised by counsel determines that the
action or proceeding so directed may not lawfully be taken or if the Guarantee
Trustee in good faith by its board of directors or trustees, executive
committee, or a trust committee of directors or trustees and/or Responsible
Officers of the Guarantee Trustee shall determine that the action or proceedings
so directed would involve the Guarantee Trustee in personal liability; and (iv)
if the Guarantee Trustee fails to enforce this Guarantee Agreement as provided
in clauses (ii) and (iii) above, any Holder may institute a legal proceeding
directly against the Guarantor to enforce its rights under this Guarantee
Agreement, without first instituting a legal proceeding against the Issuer, the
Guarantee Trustee or any other Person. Notwithstanding the foregoing, if the
Guarantor has failed to make a Guarantee Payment, a Holder may directly
institute a proceeding against the Guarantor for enforcement of this Guarantee
Agreement for such payment without first instituting a legal proceeding against
the Issuer, the Guarantee Trustee or any other Person.

Section 5.05 Guarantee of Payment.

This Guarantee Agreement creates a guarantee of payment and not merely of
collection. This Guarantee Agreement will not be discharged except by payment of
the Guarantee Payments in full (without duplication of amounts theretofore paid
by the Issuer) or upon the distribution of the Debentures to the Holders as
provided in the Declaration.

Section 5.06 Subrogation.

The Guarantor shall be subrogated to all (if any) rights of the Holders against
the Issuer in respect of any amounts paid to the Holders by the Guarantor under
this Guarantee Agreement; provided, however, that the Guarantor shall not
(except to the extent required by mandatory provisions of law) be entitled to
enforce or exercise any rights which it may acquire by way of subrogation or any
indemnity, reimbursement or other agreement, in all cases as a result of payment
under this Guarantee Agreement, if, at the time of any such payment, any amounts
are due and unpaid under this Guarantee Agreement. If any amount shall be paid
to the Guarantor in violation of the preceding sentence, the Guarantor agrees to
hold such amount in trust for the Holders and to pay over such amount to the
Holders or to the Guarantee Trustee for remittance to the Holders.

Section 5.07 Independent Obligations.

The Guarantor acknowledges that its obligations hereunder are independent of the
obligations of the Issuer with respect to the Preferred Securities and that the
Guarantor shall be liable as principal and as debtor hereunder to make Guarantee
Payments pursuant to the terms of this Guarantee Agreement notwithstanding


                                       11
<PAGE>

the occurrence of any event referred to in subsections (a) through (g),
inclusive, of Section 5.03 hereof.

                                   ARTICLE VI
                    LIMITATION OF TRANSACTIONS; SUBORDINATION

Section 6.01 Limitation of Transactions.

So long as any Preferred Securities remain outstanding, the Guarantor (i) will
remain the sole direct or indirect owner of all of the outstanding Common
Securities and shall not cause or permit the Common Securities to be transferred
except to the extent such transfer is permitted under Section [ ] of the
Declaration; provided that any permitted successor of the Guarantor under the
Indenture may succeed to the Guarantor's direct or indirect ownership of the
Common Securities and (ii) will use reasonable efforts to cause the Issuer to
continue to be treated as a grantor trust for United States federal income tax
purposes, except in connection with a distribution of Debentures as provided in
the Declaration.

[Section 6.02 Subordination.

This Guarantee Agreement will constitute an unsecured obligation of the
Guarantor and will rank (i) subordinate and junior in right of payment to all
other liabilities of the Guarantor and any guarantees of the Guarantor relating
to such liabilities, except in each case those made pari passu or subordinate by
their terms, and (ii) senior to all capital stock [(other than the most senior
preferred stock issued from time to time, if any, by the Guarantor, which
preferred stock will rank pari passu with this Guarantee Agreement)] and to any
guarantee now or hereafter entered into by the Guarantor in respect of any of
its capital stock [(other than the most senior preferred stock issued by the
guarantor)] now or hereafter issued by the Guarantor. The Guarantor's
obligations under this Guarantee Agreement will rank pari passu with respect to
obligations under other securities (other than capital stock) the Guarantor may
issue from time to time and other guarantee agreements which it may enter into
from time to time to the extent that (i) such agreements shall provide for
comparable guarantees by the Guarantor of payment on preferred securities issued
by other trusts, partnerships or other entities affiliated with the Guarantor
that are financing vehicles of the Guarantor and (ii) the debentures or other
evidences of indebtedness of the Guarantor relating to such preferred securities
are junior subordinated, unsecured indebtedness of the Guarantor.]

                                   ARTICLE VII
                                   TERMINATION

Section 7.01 Termination.

This Guarantee Agreement shall terminate and be of no further force and effect
(i) upon full payment of the Redemption Price of all Preferred Securities, (ii)
upon the distribution of Debentures, or any securities in to which such
Debentures are convertible, to Holders and holders of Common Securities in
exchange for all of the Preferred Securities and Common Securities or (iii) upon
full payment of the amounts payable in accordance with the Declaration upon
liquidation of the Issuer. Notwithstanding the foregoing, this Guarantee
Agreement will continue to be effective or will be reinstated, as the case may
be, if at any time any Holder must restore payment of any sums paid with respect
to the Preferred Securities or under this Guarantee Agreement.

                                  ARTICLE VIII
                    LIMITATION OF LIABILITY; INDEMNIFICATION

Section 8.01 Exculpation.

(a) No Indemnified Person shall be liable, responsible or accountable in damages
or otherwise to the Guarantor or any Holder for any loss, damage or claim
incurred by reason of any act or omission performed or omitted by such
Indemnified Person in good faith in accordance with this Guarantee Agreement and
in a manner such Indemnified Person reasonably believed to be within the scope
of the authority conferred on such Indemnified Person by this Guarantee
Agreement or by law, except that an Indemnified Person shall


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<PAGE>

be liable for any such loss, damage or claim incurred by reason of such
Indemnified Person's negligence or willful misconduct with respect to such acts
or omissions.

(b) An Indemnified Person shall be fully protected in relying in good faith upon
the records of the Guarantor and upon such information, opinions, reports or
statements presented to the Guarantor by any Person as to matters the
Indemnified Person reasonably believes are within such other Person's
professional or expert competence and who has been selected with reasonable care
by or on behalf of the Guarantor, including information, opinions, reports or
statements as to the value and amount of the assets, liabilities, profits,
losses or any other facts pertinent to the existence and amount of assets from
which Distributions to Holders might properly be paid.

Section 8.02 Survive Termination.

The provisions of Sections 8.01 and 8.02 shall survive the termination of this
Guarantee Agreement or the resignation or removal of the Guarantee Trustee.

                                   ARTICLE IX
                                  MISCELLANEOUS

Section 9.01 Successors and Assigns.

All guarantees and agreements contained in this Guarantee Agreement shall bind
the successors, assignees, receivers, trustees and representatives of the
Guarantor and shall inure to the benefit of the Guarantee Trustee and the
Holders then outstanding. Except in connection with a consolidation, merger or
sale involving the Guarantor that is permitted under Article IV of the
Indenture, the Guarantor shall not assign its obligations hereunder.

Section 9.02 Amendments.

Except with respect to any changes which do not adversely affect the rights of
Holders in any material respect (in which case no consent of Holders will be
required), this Guarantee Agreement may only be amended with the prior approval
of the Guarantor, the Guarantee Trustee and the Holders of not less than a
Majority of Outstanding Preferred Securities. The provisions of Section [ ] of
the Declaration concerning meetings, and actions by written consent without a
meeting, of Holders shall apply to the giving of such approval.

Section 9.03 Notices.

Any notice, request or other communication required or permitted to be given
hereunder shall be in writing, in English, duly signed by the party giving such
notice, and delivered, telecopied or mailed by first class mail as follows:

(a) if given to the Guarantor, to the address set forth below or such other
address as the Guarantor may give notice of to the Holders:

Calpine Corporation
50 West San Fernando Street
San Jose, California 95113
Facsimile: (408) 995-0505
Attention: Lisa M. Bodensteiner, Esq.

(b) if given to the Trust, in care of the Guarantor, at the Trust's (and the
Guarantee Trustee's) address set forth below or such other address as the Trust
may give notice of to the Holders:

Calpine Capital Trust [IV][V]
c/o Calpine Corporation


                                       13
<PAGE>

50 West San Fernando Street
San Jose, California 95113
Facsimile: (408) 995-0505
Attention: Lisa M. Bodensteiner, Esq.

(c) if given to the Guarantee Trustee, to the address set forth below or such
other address as the Guarantee Trustee may give notice of to the Holders:

Wilmington Trust Company
Rodney Square North
1100 North Market Street
Wilmington, Delaware 19890
Attention: Corporate Trust Administration

(c) if given to any Holder, at the address set forth on the books and records of
the Issuer.

All notices hereunder shall be deemed to have been given when (i) received in
person, (ii) telecopied with receipt confirmed, or (iii) mailed by first class
mail, postage prepaid, when received, except that if a notice or other document
is refused delivery or cannot be delivered because of a changed address of which
no notice was given, such notice or other document shall be deemed to have been
delivered on the date of such refusal or inability to deliver.

Section 9.04 Genders.

The masculine, feminine and neuter genders used herein shall include the
masculine, feminine and neuter genders.

Section 9.05 Benefit.

This Guarantee Agreement is solely for the benefit of the Guarantee Trustee and
the Holders and, subject to Section 3.01(a), is not separately transferable from
the Preferred Securities.

Section 9.06 Governing Law.

THIS GUARANTEE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED AND INTERPRETED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK (WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAWS).

Section 9.07 Counterparts.

This Guarantee Agreement may be executed in counterparts, each of which shall be
an original; but such counterparts shall together constitute one and the same
instrument.

Section 9.08 [Exercise of Overallotment Option.

If and to the extent that Preferred Securities are issued by the Issuer upon
exercise of the overallotment option referred to in the first WHEREAS clause,
the Guarantor agrees to give prompt notice thereof to the Guarantee Trustee but
the failure to give such notice shall not relieve the Guarantor of any of its
obligations hereunder.]

Section 9.09 Limited Liability.

Neither the Guarantee Trustee nor the Holders, in their capacities as such,
shall be personally liable for any liabilities or obligations of the Guarantor
arising out of this Guarantee Agreement. The parties further hereby agree that
the Holders, in their capacities as such, shall be entitled to the same
limitation of personal liability extended to the stockholders of private
corporations for profit organized under the General Corporation Law of the State
of Delaware.

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<PAGE>

THIS GUARANTEE AGREEMENT is executed as of the day and year first above written.

                                        CALPINE CORPORATION

                                        By: _________________________
                                        Name:_______________________
                                        Title: _______________________

                                        WILMINGTON TRUST COMPANY
                                          AS GUARANTEE TRUSTEE

                                        By: _______________________
                                        Name:_____________________
                                        Title: _____________________




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