<PAGE>

                                                                    EXHIBIT 4.11

                                                               EXECUTION VERSION

--------------------------------------------------------------------------------

                      MEMBERSHIP INTEREST PLEDGE AGREEMENT
              (CalGen Expansion Company, LLC Membership Interests)

                           dated as of March 23, 2004

                                       by

                        CALPINE GENERATING COMPANY, LLC,
                                   as Pledgor

                                      and

                         CALGEN EXPANSION COMPANY, LLC,
                                   as Company

                                      and

                           WILMINGTON TRUST COMPANY,
                              as Collateral Agent

--------------------------------------------------------------------------------

<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                  Page
                                                                                  ----
<S>                                                                               <C>
ARTICLE 1. DEFINITIONS; RULES OF CONSTRUCTION...................................    3

  Section 1.1    Definitions....................................................    3
  Section 1.2    Rules of Construction..........................................    4

ARTICLE 2. PLEDGE...............................................................    5

  Section 2.1    Pledged Collateral.............................................    5
  Section 2.2    Delivery of Certificates and Instruments.......................    6
  Section 2.3    Pledgor's Rights...............................................    6
  Section 2.4    Collateral Agent Not Liable....................................    7
  Section 2.5    Attorney-in-Fact...............................................    8
  Section 2.6    Collateral Agent May Perform...................................    8
  Section 2.7    Reasonable Care................................................    8

ARTICLE 3. REPRESENTATIONS AND WARRANTIES.......................................    8

  Section 3.1    Valid Security Interest........................................    8
  Section 3.2    No Liens.......................................................    9
  Section 3.3    Chief Executive Office.........................................    9

ARTICLE 4. COVENANTS............................................................    9

  Section 4.1    Chief Executive Office.........................................    9
  Section 4.2    Supplements; Further Assurances, etc...........................    9
  Section 4.3    Amendment of LLC Agreement.....................................    9
  Section 4.4    Certification of Equity Interests..............................   10
  Section 4.5    Certificates and Instruments...................................   10
  Section 4.6    Bankruptcy.....................................................   10

ARTICLE 5. EXERCISE OF REMEDIES UPON AN EVENT OF DEFAULT........................   10

  Section 5.1    Remedies Generally.............................................   10
  Section 5.2    Sale of Pledged Collateral.....................................   10
  Section 5.3    Purchase of Pledged Collateral.................................   11
  Section 5.4    Application of Proceeds........................................   11

ARTICLE 6. MISCELLANEOUS PROVISIONS.............................................   12

  Section 6.1    Notices........................................................   12
  Section 6.2    Continuing Security Interest...................................   12
  Section 6.3    Release........................................................   12
  Section 6.4    Reinstatement..................................................   12
  Section 6.5    Independent Security...........................................   12
  Section 6.6    Amendments.....................................................   12
  Section 6.7    Successors and Assigns.........................................   13
  Section 6.8    Third Party Beneficiaries......................................   13
  Section 6.9    Survival.......................................................   13
  Section 6.10   No Waiver; Remedies Cumulative.................................   13
</TABLE>

                                       i

<PAGE>

<TABLE>
<S>                                                                                <C>
Section 6.11  Counterparts......................................................   13
Section 6.12  Headings Descriptive..............................................   13
Section 6.13  Severability......................................................   13
Section 6.14  Governing Law.....................................................   13
Section 6.15  Consent to Jurisdiction...........................................   14
Section 6.16  Waiver of Jury Trial..............................................   14
Section 6.17  Entire Agreement..................................................   14
Section 6.18  Independent Obligations...........................................   14
Section 6.19  Subrogation, Etc..................................................   14
Section 6.20  Collateral Trust Agreement........................................   15
Section 6.21  No Recourse Against Pledgor or the Company........................   15
</TABLE>

                                       ii

<PAGE>

                      MEMBERSHIP INTEREST PLEDGE AGREEMENT

            This MEMBERSHIP INTEREST PLEDGE AGREEMENT, dated as of March 23,
2004 (as amended, amended and restated, supplemented or otherwise modified from
time to time, this "Agreement"), is entered into by and among CALPINE GENERATING
COMPANY, LLC, a Delaware limited liability company ("Pledgor"), CALGEN EXPANSION
COMPANY, LLC, a Delaware limited liability company (the "Company"), and
WILMINGTON TRUST COMPANY, as collateral agent (together with its successors and
permitted assigns in such capacity, the "Collateral Agent") for the Secured
Parties (as defined in the Collateral Trust Agreement referred to below).

                                    RECITALS

            WHEREAS, Pledgor:

                  (a)   intends to issue, together with CalGen Finance Corp.
      ("CalGen Finance"), as co-issuer, on a non-recourse basis:

                        (i) $235,000,000 in aggregate principal amount of its
            First Priority Secured Floating Rate Notes due 2009 (the "First
            Priority Notes"), pursuant to the Indenture, dated as of the date
            hereof (the "First Priority Indenture"), among Pledgor, CalGen
            Finance, the guarantors party thereto from time to time and
            Wilmington Trust FSB, as trustee (together with its successors and
            permitted assigns in such capacity, the "First Priority Indenture
            Trustee");

                        (ii) $640,000,000 in aggregate principal amount of its
            Second Priority Floating Rate Notes due 2010 (the "Second Priority
            Notes"), pursuant to the Indenture, dated as of the date hereof (the
            "Second Priority Indenture"), among Pledgor, CalGen Finance, the
            guarantors party thereto from time to time and Wilmington Trust FSB,
            as trustee (together with its successors and permitted assigns in
            such capacity, the "Second Priority Indenture Trustee"); and

                        (iii) (A) $680,000,000 in aggregate principal amount of
            its Third Priority Secured Floating Rate Notes due 2011 (the "Third
            Priority Floating Rate Notes"), and (B) $150,000,000 in aggregate
            principal amount of its 11.50% Third Priority Secured Notes due 2011
            (the "Third Priority Fixed Rate Notes" and, together with the First
            Priority Notes, the Second Priority Notes and the Third Priority
            Floating Rate Notes, the "Notes"), pursuant to the Indenture, dated
            as of the date hereof (the "Third Priority Indenture" and, together
            with the First Priority Indenture and the Second Priority Indenture,
            the "Indentures"), among Pledgor, CalGen Finance, the guarantors
            party thereto from time to time and Wilmington Trust FSB, as trustee
            (together with its successors and permitted assigns in such
            capacity, the "Third Priority Indenture Trustee");
                  (b)   intends to borrow, on a non-recourse basis;

<PAGE>

                        (i) $600,000,000 in aggregate principal amount of first
            priority institutional term loans due 2009 (the "First Priority Term
            Loans"), pursuant to a Credit and Guarantee Agreement, dated as of
            the date hereof (the "First Priority Term Loan Agreement"), among
            Pledgor, the guarantors party thereto from time to time, Morgan
            Stanley Senior Funding, Inc., as the administrative agent (together
            with its successors and permitted assigns in such capacity, the
            "First Priority Term Loan Administrative Agent"), Morgan Stanley
            Senior Funding, Inc., as sole lead arranger, Morgan Stanley Senior
            Funding, Inc., as sole book-runner, and the lenders party thereto
            from time to time; and

                        (ii) $100,000,000 in aggregate principal amount of
            second priority institutional term loans due 2010 (the "Second
            Priority Term Loans" and, together with the First Priority Term
            Loans, the "Term Loans"), pursuant to a Credit and Guarantee
            Agreement, dated as of the date hereof (the "Second Priority Term
            Loan Agreement" and, together with the First Priority Term Loan
            Agreement, the "Term Loan Agreements"), among Pledgor, the
            guarantors party thereto from time to time, Morgan Stanley Senior
            Funding, Inc., as the administrative agent (together with its
            successors and permitted assigns in such capacity, the "Second
            Priority Term Loan Administrative Agent"), Morgan Stanley Senior
            Funding, Inc., as sole lead arranger, Morgan Stanley Senior Funding,
            Inc., as sole book-runner, and the lenders party thereto from time
            to time; and

                  (c)   has entered into that certain Amended and Restated
      Credit Agreement, dated as of the date hereof (the "Revolving Loan
      Agreement"), among Pledgor, the guarantors party thereto from time to
      time, the lenders party thereto from time to time, The Bank of Nova
      Scotia, as administrative agent (together with its successors and
      permitted assigns in such capacity, the "Revolver Administrative Agent"),
      and each of the other agents and arrangers party thereto, which provides
      for the borrowing on a non-recourse basis of up to $200,000,000 in
      aggregate principal amount of first priority secured revolving loans (the
      "Revolving Loans");

            WHEREAS, as a condition precedent to the effectiveness of each Term
Loan Agreement, the Revolving Loan Agreement and each Indenture, Pledgor is
required to execute and deliver this Agreement, pursuant to which Pledgor will
pledge its membership interests in the Company to the Collateral Agent;

            WHEREAS, Pledgor, Calpine CalGen Holdings, Inc., the Guarantors (as
defined in the Collateral Trust Agreement (as defined below)), the First
Priority Indenture Trustee, the Second Priority Indenture Trustee, the Third
Priority Indenture Trustee, the First Priority Term Loan Administrative Agent,
the Second Priority Term Loan Administrative Agent, the Revolver Administrative
Agent and the Collateral Agent have entered into the Collateral Trust Agreement,
dated as of the date hereof (the "Collateral Trust Agreement"), which sets forth
the terms on which Pledgor, Calpine CalGen Holdings, Inc., CalGen Finance, and
the Guarantors, among others, have appointed the Collateral Agent as agent for
the present and future holders of the Secured Obligations (as defined in the
Collateral Trust Agreement), among others, to (a) receive, hold, maintain,
administer and enforce (i) all Security Documents (as defined in the Collateral
Trust Agreement) and (ii) all interests, rights, powers and remedies of the
Collateral Agent

                                       2
<PAGE>

thereunder, and (b) distribute the proceeds of the Collateral (as defined in the
Collateral Trust Agreement) in a manner consistent with the priority of liens
established by the Collateral Trust Agreement; and

            WHEREAS, Pledgor owns 100% of the membership interests of the
Company.

                                   AGREEMENT

            NOW, THEREFORE, in consideration of the premises herein and for
other good and valuable consideration, the receipt and adequacy of which are
hereby acknowledged, Pledgor hereby agrees for the benefit of the Secured
Parties as follows:

                                   ARTICLE 1.
                       DEFINITIONS; RULES OF CONSTRUCTION

      Section 1.1 Definitions.

      (a)   For purposes of this Agreement, capitalized terms used but not
otherwise defined herein shall have the meanings set forth in the Collateral
Trust Agreement as of the date hereof or as amended in accordance with the terms
thereof.

      (b)   The following terms shall have the following respective meanings:

      "Capital Stock" shall mean:

            (1)   in the case of a corporation, corporate stock;

            (2)   in the case of an association or business entity, any and all
shares, interests, participations, rights or other equivalents (however
designated) of corporate stock;

            (3)   in the case of a partnership of limited liability company,
partnership interests (whether general or limited) or membership interests; and

            (4)   any other interest or participation that confers on a Person
the right to receive a share of the profits and losses of, or distributions of
assets of, the issuing Person, but excluding from all of the foregoing any debt
securities convertible into Capital Stock, whether or not such debt securities
include any right of participation with Capital Stock.

            "Equity Interests" shall mean Capital Stock and all warrants,
options or other rights to acquire Capital Stock (but excluding any debt
security that is convertible into, or exchangeable for, Capital Stock).

            "Event of Default" shall mean an "Event of Default" under and as
defined in any of the Indentures, any of the Term Loan Agreements, the Revolving
Loan Agreement or any other Secured Debt Document.

            "LLC Agreement" shall mean the Limited Liability Company Operating
Agreement of CalGen Expansion Company, LLC, dated as of October 31, 2002, as
amended,

                                       3
<PAGE>

supplemented or modified or replaced from time to time in accordance with the
terms hereof and thereof.

            "Pledged Collateral" shall have the meaning ascribed thereto in
Section 2.1(a).

            "UCC" shall mean the Uniform Commercial Code as the same may, from
time to time, be in effect in the State of New York; provided, however, that in
the event that, by reason of mandatory provisions of law, any or all of the
perfection or priority of the security interest in any Collateral is governed by
the Uniform Commercial Code as in effect in a jurisdiction other than the State
of New York, the term "UCC" shall mean the Uniform Commercial Code as in effect
in such other jurisdiction for purposes of the provisions hereof relating to
such perfection or priority and for purposes of definitions related to such
provisions.

      Section 1.2 Rules of Construction. Unless the context otherwise requires:

      (a)   Any of the terms used or defined herein may be used in the singular
or the plural, depending on the reference.

      (b)   Except as expressly provided in any Secured Debt Document, any
reference to any agreement or instrument shall be deemed to include a reference
to such agreement or instrument as assigned, amended, amended and restated,
supplemented, otherwise modified from time to time or replaced in accordance
with the terms of this Agreement.

      (c)   The use in this Agreement of the word "include" or "including," when
following any general statement, term or matter, shall not be construed to limit
such statement, term or matter to the specific items or matters set forth
immediately following such word or to similar items or matters, whether or not
nonlimiting language (such as "without limitation" or "but not limited to" or
words of similar import) is used with reference thereto, but rather shall be
deemed to refer to all other items or matters that fall within the broadest
possible scope of such general statement, term or matter. The word "will" shall
be construed to have the same meaning and effect as the word "shall."

      (d)   References to "Articles", "Sections" and "clauses" shall be to
Articles, Sections and clauses, respectively, of this Agreement unless otherwise
specifically provided.

      (e)   References to "Exhibits", "Annexes", "Appendices" and "Schedules"
shall be to Exhibits, Annexes, Appendices and Schedules, respectively, to this
Agreement unless otherwise specifically provided.

      (f)   The use in this Agreement of the words "herein," "hereof," and
"hereunder," and words of similar import, shall be construed to refer to this
Agreement in its entirety and not to any particular provision hereof.

            This Agreement and any documents or instruments delivered pursuant
hereto or thereto shall be construed without regard to the identity of the party
who drafted the various provisions of the same. Each and every provision of this
Agreement and any instruments and documents entered into and delivered in
connection therewith shall be construed as though the parties participated
equally in the drafting of the same. Consequently, each of the parties

                                       4
<PAGE>

acknowledges and agrees that any rule of construction that a document is to be
construed against the drafting party shall not be applicable to this Agreement
or the instruments and documents entered into and delivered in connection
therewith. If any conflict or inconsistency exists between this Agreement and
the Collateral Trust Agreement, the Collateral Trust Agreement shall govern.

                                   ARTICLE 2.
                                     PLEDGE

      Section 2.1 Pledged Collateral.

      (a)   As collateral security for the prompt and complete payment and
performance when due, whether at stated maturity, by required prepayment,
declaration, acceleration, demand or otherwise (including the payment of amounts
which would become due but for the operation of the automatic stay under Section
362(a) of the U.S. Bankruptcy Code, 11 U.S.C. Section 362(a) and any successor
provision thereof), of all of the First Priority Lien Obligations, whether now
existing or hereafter arising and howsoever evidenced, Pledgor hereby grants to
the Collateral Agent, its successors and assigns, for the benefit of the
Collateral Agent and the First Priority Secured Parties, a security interest in
the following, whether now existing or hereafter from time to time acquired
(collectively, the "Pledged Collateral"):

            (i)   all of Pledgor's Equity Interests in the Company and all of
Pledgor's rights to acquire membership or other Equity Interests in the Company
in addition to or in exchange or substitution for any Equity Interests in the
Company;

            (ii)  all of Pledgor's rights, privileges, authority and powers as
an owner of Equity Interests in the Company under the LLC Agreement;

            (iii) all certificates or other documents (if any) representing any
and all of the foregoing in clauses (i) and (ii), including, without limitation,
the certificates listed on Schedule I hereto;

            (iv)  all dividends, distributions, cash, securities, instruments
and other property or proceeds of any kind to which Pledgor may be entitled in
its capacity as an owner of Equity Interests in the Company by way of
distribution, return of capital or otherwise;

            (v)   any other claim which Pledgor now has or may in the future
acquire in its capacity as an owner of Equity Interests in the Company against
the Company and its property; and

            (vi)  all proceeds, products and accessions of and to any of the
property described in the preceding clauses (i) through (v).

      (b)   As collateral security for the prompt and complete payment and
performance when due, whether at stated maturity, by required prepayment,
declaration, acceleration, demand or otherwise (including the payment of amounts
which would become due but for the operation of the automatic stay under Section
362(a) of the U.S. Bankruptcy Code, 11 U.S.C. Section 362(a) and any successor
provision thereof), of all of the Second Priority Lien Obligations, whether now

                                       5
<PAGE>

existing or hereafter arising and howsoever evidenced, Pledgor hereby grants to
the Collateral Agent, its successors and assigns, for the benefit of the
Collateral Agent and the Second Priority Secured Parties, a security interest in
the Pledged Collateral.

      (c)   As collateral security for the prompt and complete payment and
performance when due, whether at stated maturity, by required prepayment,
declaration, acceleration, demand or otherwise (including the payment of amounts
which would become due but for the operation of the automatic stay under Section
362(a) of the U.S. Bankruptcy Code, 11 U.S.C. Section 362(a) and any successor
provision thereof), of all of the Third Priority Lien Obligations, whether now
existing or hereafter arising and howsoever evidenced, Pledgor hereby grants to
the Collateral Agent, its successors and assigns, for the benefit of the
Collateral Agent and the Third Priority Secured Parties, a security interest in
the Pledged Collateral.

      (d)   As used herein, the term "proceeds" shall be construed in its
broadest sense and shall include whatever is received or receivable when any of
the property described in clauses (i) through (v) of Section 2.1(a), or any
proceeds thereof, are sold, collected, exchanged or otherwise disposed of,
whether voluntarily or involuntarily, and shall include, without limitation, all
rights to payment, including interest and premiums, with respect to any such
property or any proceeds thereof.

      Section 2.2 Delivery of Certificates and Instruments. All certificates or
instruments representing or evidencing the Pledged Collateral, if any, shall be
delivered to and held by or on behalf of the Collateral Agent in accordance with
Section 4.5 and shall be in suitable form for transfer by delivery, or shall be
accompanied by duly executed, undated instruments of transfer or assignment in
blank, all in form and substance reasonably satisfactory to the Collateral
Agent. The Collateral Agent shall have the right, at any time following the
occurrence and during the continuation of an Event of Default (but subject to
the terms of the Collateral Trust Agreement including, without limitation, the
receipt of lawful directions given to it pursuant to such terms), without notice
to Pledgor, to transfer to or to register in its name or in the name of any of
its nominees any or all of the Pledged Collateral.

      Section 2.3 Pledgor's Rights.

      (a)   Voting Rights.

            (i)   Unless an Event of Default shall have occurred and be
continuing and written notice shall have been provided by the Collateral Agent
to Pledgor (provided that if an Insolvency Proceeding shall have occurred with
respect to Pledgor, such written notice shall not be required and shall be
deemed to have been received by Pledgor upon the occurrence of such Event of
Default), Pledgor shall be entitled to exercise all voting and other rights with
respect to the Pledged Collateral; provided, however, that no vote shall be
cast, right exercised or other action taken which would result in any violation
of any provision of this Agreement or any other Secured Debt Document.

            (ii)  Upon the occurrence and during the continuation of an Event of
Default and upon written notice from the Collateral Agent to Pledgor (provided
that if an Insolvency Proceeding shall have occurred with respect to Pledgor,
such written notice shall not be required

                                       6
<PAGE>

and shall be deemed to have been received by Pledgor upon the occurrence of such
Event of Default), all voting and other rights of Pledgor with respect to the
Pledged Collateral which Pledgor would otherwise be entitled to exercise
pursuant to the terms of this Agreement or otherwise shall cease, and all such
rights shall be vested in the Collateral Agent which shall thereupon have the
sole right to exercise such rights. After all Events of Default have been cured
or waived and Pledgor has delivered to the Collateral Agent a certificate to
that effect, Pledgor's rights under this Section 2.3 shall be reinstated.

      (b)   Distributions.

            (i)   Unless an Event of Default shall have occurred and be
continuing and written notice shall have been provided by the Collateral Agent
to Pledgor (provided that if an Insolvency Proceeding shall have occurred with
respect to Pledgor, such written notice shall not be required and shall be
deemed to have been received by Pledgor upon the occurrence of such Event of
Default), Pledgor shall be entitled to receive and retain any and all dividends,
interest, principal and other distributions paid on or distributed in respect of
the Pledged Collateral to the extent and only to the extent that all such
dividends, interest, principal and other distributions are permitted by, and
otherwise paid or distributed in accordance with, the terms and conditions of
the Secured Debt Documents.

            (ii)  Upon the occurrence and during the continuation of an Event of
Default and upon written notice from the Collateral Agent to Pledgor (provided
that if an Insolvency Proceeding shall have occurred with respect to Pledgor,
such written notice shall not be required and shall be deemed to have been
received by Pledgor upon the occurrence of such Event of Default), all rights of
Pledgor to the dividends, interest, principal and other distributions shall
cease and all such rights shall be vested in the Collateral Agent which shall
thereupon have the sole right to receive such distributions. After all Events of
Defaults have been cured or waived and Pledgor has delivered to the Collateral
Agent a certificate to that effect, Pledgor's rights under this Section 2.3
shall be reinstated.

      (c)   Turnover. All distributions and other amounts which are received by
Pledgor contrary to the provisions of this Agreement shall be received in trust
for the benefit of the Collateral Agent, shall be segregated from other funds of
Pledgor and shall be forthwith paid over to the Collateral Agent as Pledged
Collateral in the same form as so received (with any necessary endorsement
requested by Collateral Agent).

      Section 2.4 Collateral Agent Not Liable. Notwithstanding any other
provision contained in this Agreement, Pledgor shall remain liable under the LLC
Agreement to observe and perform all of the conditions and obligations to be
observed and performed by Pledgor thereunder. The powers conferred on the
Collateral Agent hereunder are solely to protect its interest in the Pledged
Collateral and the interests of the Secured Parties and shall not impose any
duty upon it to exercise any such powers. Neither the Collateral Agent, its
Affiliates nor any of their directors, officers, employees, Affiliates or agents
shall be liable for acting in any way hereunder, for failure to demand, collect
or realize upon all or any part of the Pledged Collateral or for any delay in
doing so or shall be under any obligation to sell or otherwise dispose of any
Pledged Collateral upon the request of Pledgor or otherwise.

                                       7
<PAGE>

      Section 2.5 Attorney-in-Fact. Pledgor hereby appoints the Collateral
Agent, on behalf of the Secured Parties, as its true and lawful attorney-in-fact
and proxy, with full power and authority in the place and stead of Pledgor and
in the name of Pledgor or in its own name, at Pledgor's cost and expense, to the
extent reasonable, from time to time to take any action and to execute any
instrument which may be reasonably necessary to enforce its rights under this
Agreement, including, without limitation, authority to receive, endorse and
collect all instruments made payable to Pledgor representing any distribution,
interest payment or other payment in respect of the Pledged Collateral or any
part thereof to be paid over to the Collateral Agent pursuant to Sections 2.3
(b) and (c) and to give full discharge for the same.

      Section 2.6 Collateral Agent May Perform. If Pledgor fails to perform any
agreement contained herein after receipt of a written request to do so from the
Collateral Agent, the Collateral Agent may (but shall not be obligated to)
itself perform, or cause performance of, such agreement, and the expenses of the
Collateral Agent, including the reasonable fees and expenses of its counsel,
incurred in connection therewith shall be payable by the Company under Section
8.7 of the Collateral Trust Agreement; provided that if an Insolvency Proceeding
shall have occurred with respect to Pledgor, the written request described in
this Section 2.6 shall not be required and shall be deemed to have been received
by Pledgor upon the failure of Pledgor to perform such agreement.

      Section 2.7 Reasonable Care. The Collateral Agent shall be deemed to have
exercised reasonable care in the custody and preservation of the Pledged
Collateral in its possession if the Pledged Collateral is accorded treatment
substantially equivalent to that which the Collateral Agent accords its own
property of the type of which the Pledged Collateral consists, it being
understood that the Collateral Agent shall have no responsibility for (a)
ascertaining or taking action with respect to calls, conversions, exchanges,
maturities, tenders or other matters relative to any Pledged Collateral, whether
or not the Collateral Agent has or is deemed to have knowledge of such matters,
or (b) taking any necessary steps to preserve rights against any parties with
respect to any Pledged Collateral.

                                  ARTICLE 3.
                         REPRESENTATIONS AND WARRANTIES

            Pledgor represents and warrants to the Collateral Agent for its
benefit and the benefit of the Secured Parties, as of the Closing Date, as
follows, which representations and warranties shall survive the execution and
delivery of this Agreement:

      Section 3.1 Valid Security Interest. When UCC financing statements naming
Pledgor as "debtor" and Collateral Agent as "secured party" and describing the
Pledged Collateral are filed in the appropriate filing offices, this Agreement
will create a perfected security interest in all right, title and interest of
Pledgor in the Pledged Collateral, to the extent perfection can be obtained by
filing UCC financing statements in such jurisdictions. When Pledged Collateral
constituting certificated securities (as defined in the UCC) is delivered to the
Collateral Agent, together with instruments of transfer duly endorsed in blank,
this Agreement will create a perfected security interest in all right, title
and interest of Pledgor in such certificated securities to the extent perfection
is governed by the UCC as in effect in any applicable jurisdiction.

                                       8
<PAGE>

      Section 3.2 No Liens. Pledgor is the owner of all of its right, title and
interest in the Pledged Collateral free from any Liens other than the Liens
created pursuant to this Agreement and other Permitted Liens.

      Section 3.3 Chief Executive Office. As of the Closing Date, the chief
executive office of Pledgor and the office where Pledgor keeps its records
concerning the Pledged Collateral is located at:

                  Calpine Generating Company, LLC
                  c/o Calpine Corporation
                  50 West San Fernando Street
                  San Jose, California 95113

Pledgor's taxpayer identification number is 77-0555128 and Pledgor's
organizational identification number with the State of Delaware is 3282581. The
name of Pledgor is Calpine Generating Company, LLC, as indicated on the public
record of the State of Delaware.

                                   ARTICLE 4.
                                   COVENANTS

            Pledgor hereby covenants and agrees from and after the date of this
Agreement until the termination of this Agreement in accordance with the
provisions of Section 6.3 hereof:

      Section 4.1 Chief Executive Office. Pledgor shall not establish a new
location for its chief executive office, change its state of incorporation or
change its name until (i) it has given to the Collateral Agent not less than
thirty (30) days prior written notice of its intention so to do, clearly
describing such new location or specifying such new state or name, as the case
may be, and (ii) with respect to such new location or such new state or name, as
the case may be, it shall have taken all action necessary to maintain the
security interest of the Collateral Agent in the Pledged Collateral intended to
be granted hereby at all times fully perfected and in full force and effect.

      Section 4.2 Supplements; Further Assurances, etc. Pledgor shall at any
time and from time to time, at the expense of Pledgor, promptly execute and
deliver all further instruments and documents, and take all further action, that
the Collateral Agent may reasonably request, in order to perfect any security
interest granted or purported to be granted hereby in the Pledged Collateral or
to enable the Collateral Agent to exercise and enforce its rights and remedies
hereunder with respect to any Pledged Collateral.

      Section 4.3 Amendment of LLC Agreement. Pledgor shall not, without the
prior written consent of the Collateral Agent, agree to or permit (a) the
cancellation or termination of the LLC Agreement, except upon the expiration of
the stated term thereof, or (b) any amendment, supplement or modification of, or
waiver with respect to any of the provisions of, the LLC Agreement, in either
case, that is prohibited by the Secured Debt Documents; provided, that Pledgor
agrees that it shall not, without the prior written consent of the Collateral
Agent, amend or modify the LLC Agreement in any manner which would expressly
restrict the

                                       9
<PAGE>

Collateral Agent's ability to exercise remedies in respect of the Pledged
Collateral as and to the extent contemplated hereby.

      Section 4.4 Certification of Equity Interests. The Equity Interests in the
Company pledged hereunder shall be "certificated securities" under the UCC.

      Section 4.5 Certificates and Instruments. Pledgor shall deliver all
certificates or other instruments representing the Pledged Collateral to the
Collateral Agent with all necessary instruments of transfer or assignment duly
indorsed in blank. In the event Pledgor obtains possession of any certificates,
or any securities or instruments forming a part of the Pledged Collateral,
Pledgor shall promptly deliver the same to the Collateral Agent together with
all necessary instruments of transfer or assignment duly indorsed in blank.
Prior to any such delivery, any Pledged Collateral in Pledgor's possession shall
be held by Pledgor in trust for the Collateral Agent.

      Section 4.6 Bankruptcy. Pledgor shall not authorize or permit the Company
to (a) commence a voluntary case or other proceeding seeking liquidation,
reorganization or other relief with respect to the Company or the Company's
debts under any Bankruptcy Law now or hereafter in effect or seeking the
appointment of a trustee, receiver, liquidator, custodian or other similar
official of the Company or any substantial part of the Company's property, (b)
consent to any such relief or to the appointment of or taking possession by any
such official in an involuntary case or other proceeding commenced against the
Company or (c) make a general assignment for the benefit of the Company's
creditors. Pledgor shall not commence or join with any other Person (other than
the Collateral Agent and the other Secured Parties) in commencing any proceeding
against the Company under any Bankruptcy Law or any similar statute now or
hereafter in effect in any jurisdiction.

                                   ARTICLE 5.
                 EXERCISE OF REMEDIES UPON AN EVENT OF DEFAULT

      Section 5.1 Remedies Generally. If an Event of Default shall have occurred
and be continuing, the Collateral Agent may exercise in respect of the Pledged
Collateral, in addition to all other rights and remedies granted in this
Agreement and in any other instrument or agreement securing, evidencing or
relating to the Secured Obligations, all rights and remedies of a secured party
under the UCC and all other rights and remedies available at law or in equity,
in each case subject to and in accordance with the Collateral Trust Agreement.

      Section 5.2 Sale of Pledged Collateral

      (a)   Without limiting the generality of Section 5.1, if an Event of
Default shall have occurred and be continuing, the Collateral Agent may, without
notice except as specified below, sell the Pledged Collateral or any part
thereof in one or more parcels at public or private sale or at any of the
Collateral Agent's corporate trust offices or elsewhere, for cash, on credit or
for future delivery, and at such price or prices and upon such other terms as
are commercially reasonable, irrespective of the impact of any such sales on the
market price of the Pledged Collateral at any such sale. Each purchaser at any
such sale shall hold the property sold absolutely, free from any claim or right
on the part of Pledgor, and Pledgor hereby waives (to the

                                       10
<PAGE>

extent permitted by law) all rights of redemption, stay and/or appraisal which
it now has or may at any time in the future have under any rule of law or
statute now existing or hereafter enacted. Pledgor agrees that at least ten (10)
days notice to Pledgor of the time and place of any public sale or the time
after which any private sale is to be made shall constitute reasonable
notification. The Collateral Agent shall not be obligated to make any sale of
Pledged Collateral regardless of notice of sale having been given. The
Collateral Agent may adjourn any public or private sale from time to time by
announcement at the time and place fixed therefor, and such sale may, without
further notice, be made at the time and place to which it was so adjourned. The
Collateral Agent shall incur no liability as a result of the sale of the Pledged
Collateral, or any part thereof, at any public or private sale. Pledgor hereby
waives any claims against the Collateral Agent arising by reason of the fact
that the price at which any Pledged Collateral may have been sold at such a
private sale, if commercially reasonable, was less than the price which might
have been obtained at a public sale, even if the Collateral Agent accepts the
first offer received and does not offer the Pledged Collateral to more than one
offeree.

      (b)   Pledgor recognizes that, if an Event of Default shall have occurred
and be continuing, the Collateral Agent may elect to sell all or any part of the
Pledged Collateral to one or more purchasers in privately negotiated
transactions in which the purchasers will be obligated to agree, among other
things, to acquire the Pledged Collateral for their own account, for investment
and not with a view to the distribution or resale thereof. Pledgor acknowledges
that any such private sales may be at prices and on terms less favorable than
those obtainable through a public sale (including, without limitation, a public
offering made pursuant to a registration statement under the Securities Act),
and Pledgor and the Collateral Agent agree that such private sales shall be made
in a commercially reasonable manner and that the Collateral Agent has no
obligation to engage in public sales and no obligation to delay sale of any
Pledged Collateral to permit the issuer thereof to register the Pledged
Collateral for a form of public sale requiring registration under the Securities
Act. If the Collateral Agent determines to exercise its right to sell any or all
of the Pledged Collateral, upon written request Pledgor shall, from time to
time, furnish to the Collateral Agent all such information as is necessary in
order to determine the number of shares and other instruments included in the
Pledged Collateral which may be sold by the Collateral Agent as exempt
transactions under the Securities Act and rules of the SEC thereunder, as the
same are from time to time in effect.

      Section 5.3 Purchase of Pledged Collateral. The Collateral Agent may be a
purchaser of the Pledged Collateral or any part thereof or any right or interest
therein at any sale thereof, whether pursuant to foreclosure, power of sale or
otherwise hereunder and the Collateral Agent may apply the purchase price to the
payment of the Secured Obligations. Any purchaser of all or any part of the
Pledged Collateral shall, upon any such purchase, acquire good title to the
Pledged Collateral so purchased, free of the security interests created by this
Agreement.

      Section 5.4 Application of Proceeds. The Collateral Agent shall apply any
proceeds from time to time held by it and the net proceeds of any collection,
recovery, receipt, appropriation, realization or sale with respect to the
Pledged Collateral in accordance with and subject to the Collateral Trust
Agreement. For avoidance of doubt, it is understood that the Company shall
remain liable to the extent of any deficiency between the amount of proceeds of
the Pledged Collateral and the aggregated amount of the Secured Obligations.

                                       11
<PAGE>

                                   ARTICLE 6.
                            MISCELLANEOUS PROVISIONS

      Section 6.1 Notices. Unless otherwise specifically herein provided, any
notice or other communication required or permitted under the terms and
provisions hereof shall be in writing and any such notice shall become effective
if given in accordance with the provisions of Section 8.5 of the Collateral
Trust Agreement.

      Section 6.2 Continuing Security Interest This Agreement shall create a
continuing security interest in the Pledged Collateral until the release thereof
pursuant to Section 6.3.

      Section 6.3 Release. Upon the Secured Obligations Termination Date, or any
sale or other transfer of the Pledged Collateral permitted under this Agreement
and the other Secured Debt Documents, the Collateral Agent, upon the request,
and at the expense, of Pledgor, and acting pursuant to written instructions from
Pledgor, shall execute and deliver all such documentation as Pledgor may
reasonably request to release the security interest created pursuant to this
Agreement.

      Section 6.4 Reinstatement. This Agreement shall continue to be effective
or be reinstated, as the case may be, if at any time any amount received by the
Collateral Agent or any other Secured Party hereunder or pursuant hereto is
rescinded or must otherwise be restored or returned by the Collateral Agent or
such Secured Party upon a Bankruptcy Event of Pledgor, the Company or any of the
Guarantors or upon the appointment of any intervenor or conservator of, or
trustee or similar official for, Pledgor, the Company or any of the Guarantors
or any substantial part of Pledgor, the Company or any of the Guarantors'
assets, or upon the entry of an order by any court avoiding the payment of such
amount, or otherwise, all as though such payments had not been made.

      Section 6.5 Independent Security. The security provided for in this
Agreement shall be in addition to and shall be independent of every other
security which the Secured Parties may at any time hold for any of the Secured
Obligations hereby secured, whether or not under the Security Documents. The
execution of any other Security Document shall not modify or supersede the
security interest or any rights or obligations contained in this Agreement and
shall not in any way affect, impair or invalidate the effectiveness and validity
of this Agreement or any term or condition hereof. Pledgor hereby waives its
right to plead or claim in any court that the execution of any other Security
Document is a cause for extinguishing, invalidating, impairing or modifying the
effectiveness and validity of this Agreement or any term or condition contained
herein. The Collateral Agent shall be at liberty to accept further security from
Pledgor or from any third party and/or release such security without notifying
Pledgor and without affecting in any way the obligations of Pledgor under the
this Agreement. The Collateral Agent shall determine if any security conferred
upon the Secured Parties under the Security Documents shall be enforced by the
Collateral Agent, as well as the sequence of securities to be so enforced.

      Section 6.6 Amendments. No waiver, amendment, modification or termination
of any provision of this Agreement, or consent to any departure by Pledgor or
the Company therefrom, shall in any event be effective without the prior written
consent of each of the parties hereto, and none of the Pledged Collateral shall
be released without the written consent of the Collateral

                                       12
<PAGE>

Agent. Any such waiver or consent shall be effective only in the specific
instance and for the specific purpose for which given.

      Section 6.7 Successors and Assigns. This Agreement shall be binding upon
Pledgor and the Company and their respective successors, transferees and assigns
and shall inure to the benefit of the Collateral Agent and the other Secured
Parties and their respective successors, transferees and assigns. Neither
Pledgor nor the Company shall assign or otherwise transfer any of its rights or
obligations under this Agreement without the written consent of the Collateral
Agent.

      Section 6.8 Third Party Beneficiaries. The agreements of the parties
hereto are intended to benefit the Secured Parties and their respective
successors and assigns.

      Section 6.9 Survival. All agreements, statements, representations and
warranties made by Pledgor and the Company herein or in any certificate or other
instrument delivered by Pledgor or on its behalf under this Agreement shall be
considered to have been relied upon by the Collateral Agent and the other
Secured Parties and shall survive the execution and delivery of this Agreement
until termination hereof or the indefeasible payment in full in cash or Cash
Equivalents of all of the Secured Obligations regardless of any investigation
made by the Collateral Agent or the other Secured Parties or made on their
behalf.

      Section 6.10 No Waiver, Remedies Cumulative. No failure or delay on the
part of the Collateral Agent in exercising any right, power or privilege
hereunder and no course of dealing between any of the parties hereto shall
operate as a waiver thereof; nor shall any single or partial exercise of any
right, power or privilege hereunder preclude any other or further exercise
thereof or the exercise of any other right, power or privilege hereunder or
thereunder. The rights and remedies herein expressly provided are cumulative and
not exclusive of any rights or remedies which the Collateral Agent would
otherwise have.

      Section 6.11 Counterparts. This Agreement may be executed in any number of
counterparts and by the different parties hereto on separate counterparts, each
of which when so executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument.

      Section 6.12 Headings Descriptive. The headings of the several sections
and subsections of this Agreement are inserted for convenience only and shall
not in any way affect the meaning or construction of any provision of this
Agreement.

      Section 6.13 Severability. in case any provision contained in or
obligation under this Agreement shall be invalid, illegal or unenforceable in
any jurisdiction, the validity, legality and enforceability of the remaining
provisions or obligations, or of such provision or obligation in any other
jurisdiction, shall not in any way be affected or impaired thereby.

      Section 6.14 Governing Law. This Agreement shall be governed by the laws
of the State of New York of the United States of America and shall for all
purposes be governed by and construed in accordance with the laws of such state
without regard to the conflict of law rules thereof other than Section 5-1401 of
the New York General Obligations Law.

                                       13

<PAGE>

      Section 6.15 Consent to Jurisdiction. ALL JUDICIAL PROCEEDINGS BROUGHT
AGAINST PLEDGOR OR THE COMPANY ARISING OUT OF OR RELATING HERETO OR ANY OTHER
TRANSACTION DOCUMENT, OR ANY OF THE OBLIGATIONS, MAY BE BROUGHT IN ANY STATE OR
FEDERAL COURT OF COMPETENT JURISDICTION IN THE STATE, COUNTY AND CITY OF NEW
YORK. BY EXECUTING AND DELIVERING THIS AGREEMENT, EACH PARTY, FOR ITSELF AND IN
CONNECTION WITH ITS PROPERTIES, IRREVOCABLY ACCEPTS GENERALLY AND
UNCONDITIONALLY THE NONEXCLUSIVE JURISDICTION AND VENUE OF SUCH COURTS; WAIVES
ANY DEFENSE OF FORUM NON CONVENIENS; AGREES THAT SERVICE OF ALL PROCESS IN ANY
SUCH PROCEEDING IN ANY SUCH COURT MAY BE MADE BY REGISTERED OR CERTIFIED MAIL,
RETURN RECEIPT REQUESTED, TO THE APPLICABLE PARTY IN ACCORDANCE WITH SECTION
6.1; AGREES THAT SERVICE AS PROVIDED ABOVE IS SUFFICIENT TO CONFER PERSONAL
JURISDICTION OVER IT, AS APPLICABLE, IN ANY SUCH PROCEEDING IN ANY SUCH COURT,
AND OTHERWISE CONSTITUTES EFFECTIVE AND BINDING SERVICE IN EVERY RESPECT; AND
AGREES THAT THE SERVICE PROCESS MAY BE MADE IN ANY OTHER MANNER PERMITTED BY LAW
OR TO BRING PROCEEDINGS AGAINST ANY PARTY HERETO IN THE COURTS OF ANY OTHER
JURISDICTION.

      Section 6.16 Waiver of Jury Trial. EACH OF THE PARTIES HERETO HEREBY
KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES ANY RIGHTS IT MAY HAVE TO A
TRIAL BY JURY IN RESPECT OF ANY LITIGATION BASED HEREON, OR ARISING OUT OF,
UNDER OR IN CONNECTION WITH, THIS AGREEMENT, OR ANY COURSE OF CONDUCT, COURSE OF
DEALING, STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF THE OTHER PARTIES
HERETO. THIS PROVISION IS A MATERIAL INDUCEMENT FOR THE COLLATERAL AGENT TO
ENTER INTO THIS AGREEMENT.

      Section 6.17 Entire Agreement. This Agreement, together with any other
agreement executed in connection herewith (including the Collateral Trust
Agreement), is intended by the parties as a final expression of their agreement
as to the matters covered hereby and is intended as a complete and exclusive
statement of the terms and conditions thereof.

      Section 6.18 Independent Obligations. Pledgor's obligations under this
Agreement are independent of those of the Company. The Collateral Agent may
bring a separate action against Pledgor without first proceeding against the
Company or any other Person or any other security held by the Collateral Agent
and without pursuing any other remedy.

      Section 6.19 Subrogation. Etc. Notwithstanding any payment or payments
made by Pledgor or the exercise by the Collateral Agent of any of the remedies
provided under this Agreement or any other Secured Debt Document, until the
Secured Obligations Termination Date, Pledgor shall have no claim (as defined in
11 U.S.C. Section 101(5)) of subrogation to any of the rights of the Collateral
Agent against the Company, the Pledged Collateral or any guaranty held by the
Collateral Agent for the satisfaction of any of the Secured Obligations, nor
shall Pledgor have any claims (as defined in 11 U.S.C. Section 101(5)) for
reimbursement, indemnity, exoneration or contribution from the Company in
respect of payments made by Pledgor hereunder. Notwithstanding the foregoing, if
any amount shall be paid to Pledgor on account of such

                                       14
<PAGE>

subrogation, reimbursement, indemnity, exoneration or contribution rights at any
time, such amount shall be held by Pledgor in trust for the Collateral Agent
segregated from other funds of Pledgor, and shall be turned over to the
Collateral Agent in the exact form received by Pledgor (duly endorsed by Pledgor
to the Collateral Agent if required) to be applied against the Secured
Obligations in such amounts and in such order as the Collateral Agent may elect.

      Section 6.20 Collateral Trust Agreement. All the provisions contained in
this Agreement are expressly subject to all of the provisions contained in the
Collateral Trust Agreement in all respects. The rights, powers, benefits,
privileges, immunities and indemnities given to the Collateral Agent and set
forth in the Collateral Trust Agreement are hereby expressly incorporated herein
and shall survive the termination of this Agreement and the resignation or
removal of the Collateral Agent.

      Section 6.21 No Recourse Against Pledgor or the Company. NOTWITHSTANDING
ANYTHING TO THE CONTRARY SET FORTH IN THIS AGREEMENT OR ANY OTHER SECURED DEBT
DOCUMENT, THE NOTES, THE TERM LOANS, THE REVOLVING LOANS AND ALL RELATED
GUARANTEES ARE NON-RECOURSE SECURED OBLIGATIONS OF PLEDGOR, THE COMPANY AND THE
GUARANTORS PARTY THERETO, AS APPLICABLE. THE ONLY RECOURSE A SECURED PARTY WILL
HAVE WITH RESPECT TO THE PAYMENT OF PRINCIPAL OF, OR INTEREST OR PREMIUM ON, ANY
OF THE FOREGOING OBLIGATIONS WILL BE ENFORCEMENT OF ITS RIGHTS AGAINST THE
COLLATERAL PURSUANT TO THE SECURITY DOCUMENTS.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       15
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused this Membership
Interest Pledge Agreement to be duly executed and delivered by their officers
thereunto duly authorized as of the date first above written.

                                          CALPINE GENERATING COMPANY, LLC,
                                          a Delaware limited liability company

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

                                          CALGEN EXPANSION COMPANY, LLC,
                                          a Delaware limited liability company

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

[Calpine Generating Company, LLC-Pledge Agreement]

<PAGE>

                                          WILMINGTON TRUST COMPANY,
                                          as Collateral Agent

                                          By: /s/ James J. McGinley
                                              ----------------------------------
                                          Name: James J. McGinley
                                          Title: Athorized Signer

[Calpine Generating Company, LLC - Pledge Agreement]

<PAGE>

                                                                      Schedule I
                                                             to Pledge Agreement

                                  CERTIFICATES

LLC Interest Certificate No. 2 in CalGen Expansion Company, LLC

<PAGE>

UCC FINANCING STATEMENT

FOLLOW INSTRUCTIONS (front and back) CAREFULLY

A. NAME & PHONE OF CONTACT AT FILER [optional]

B. SEND ACKNOWLEDGMENT TO: (Name and Address)

                 THE ABOVE SPACE IS FOR FILING OFFICE USE ONLY

<TABLE>
<S>                                                      <C>                        <C>                               <C>
1. DEBTOR'S EXACT FULL LEGAL NAME- Insert only one debtor name (1a or 1b)- do
not abbreviate or combine names

   1a. ORGANIZATION'S NAME
   Calpine Generating Company, LLC
OR
   1b. INDIVIDUAL'S LAST NAME                            FIRST NAME                 MIDDLE NAME                       SUFFIX

1c. MAILING ADDRESS                                        CITY                     STATE    POSTAL CODE              COUNTRY
c/o Calpine Corporation, 50 West San Fernando Street     San Jose                    CA      95113                     U.S.A.

1d. TAX ID # SSN OR EIN  ADDL. INFO RE  1e. TYPE OF      1f. JURIDICTION OF         1g. ORGANIZATIONAL ID #, if any
                        ORGANIZATION   ORGANIZATION      ORGANIZATION
                        DEBTOR         LLC               Delaware                   DE3282581                         [ ] NONE

2. ADDITIONAL DEBTOR'S EXACT FULL LEGAL NAME - Insert only one debtor name (2a
or 2b)- do not abbreviate or combine names

   2a. ORGANIZATION'S NAME
OR
   2b. INDIVIDUAL'S LAST NAME                            FIRST NAME                 MIDDLE NAME                       SUFFIX

2c. MAILING ADDRESS                                        CITY                     STATE    POSTAL CODE              COUNTRY

2d. TAX ID # SSN OR EIN  ADDL INFO RE  2e. TYPE OF       2f. JURISDICTION OF        2g. ORGANIZATIONAL ID #, if any
                        ORGANIZATION   ORGANIZATION      ORGANIZATION
                        DEBTOR                                                                                        [ ] NONE

3. SECURED PARTY'S NAME (or NAME of TOTAL ASSIGNEE of ASSIGNOR S/P) - Insert
only one secured party name (3a or 3b)

   3a. ORGANIZATION'S NAME
   Wilmington Trust Company, as Collateral Agent
OR
   3b. INDIVIDUAL'S LAST NAME                            FIRST NAME                 MIDDLE NAME                       SUFFIX

3c. MAILING ADDRESS                                        CITY                     STATE    POSTAL CODE              COUNTRY

Rodney Square N., 1100 N. Market St. Attn : Corp. Capital  Wilmiagton                DE      19890                     U.S.A.
Mkts.
</TABLE>

4. This FINANCING STATEMENT covers the following Collateral:

   See Exhibit A attached hereto.

<TABLE>
<S>                           <C>             <C>                   <C>             <C>                 <C>          <C>
5. ALTERNATIVE DESIGNATION    LESSEE/LESSOR   CONSIGNEE/CONSIGNOR   BAILEE/BAILOR   SELLER/BUYER        AG.LIEN      NON-UCC FILING
   [if applicable]:
</TABLE>

<TABLE>
<S>                                            <C>                                                 <C>          <C>       <C>
6.  This FINANCING STATEMENT is to be filed    7. Check to REQUEST SEARCH REPORT(S) on Debtor(s)
    [for record] (or recorded) in the REAL
     ESTATE      RECORDS     [if applicable]      [ADDITIONAL FEE]              [optional]         All Debtors  Debtor 1  Debtor 2
     Attach     Addendurn
</TABLE>

8. OPTIONAL FILER REFERENCE DATA
   TO BE FILED WITH THE SECTRETARY OF STATE OF DELAWARE.

FILING OFFICE COPY -NATIONAL UCC FINANCING STATEMENT (FORM UCC1)(REV. 07/29/98)

<PAGE>

DEBTOR:                 CALPINE GENERATING COMPANY, LLC

SECURED PARTY:          WILMINGTON TRUST COMPANY, AS COLLATERAL AGENT

                               EXHIBIT A TO UCC1

This financing statement covers all the estate, right, title and interest of
Debtor, now owned or hereafter acquired, in, to and under any and all of the
following (the "Collateral"):

(i) all of Debtor's Equity Interests (the "Equity Interests"), as defined more
fully in that certain Membership Interest Pledge Agreement, dated as of March
23, 2004, by and among Debtor, Company, and Secured Party (the "Pledge
Agreement") in CalGen Expansion Company, LLC, a Delaware limited liability
company (the "Company") and all of Debtor's rights to acquire membership or
other Equity Interests in the Company in addition to or in exchange or
substitution for any Equity Interests in the Company;

(ii) all of Debtor's rights, privileges, authority and powers as an owner of
Equity Interests in the Company under that certain Limited Liability Company
Operating Agreement of Company, dated as of October 31,2002, as amended,
supplemented or modified or replaced from time to time(the "LLC Agreement");

(iii) all certificates or other documents (if any) representing any and all of
the foregoing in clauses (i) and (ii), including, without limitation, the
certificates listed on Schedule I to the Pledge Agreement;

(iv) all dividends, distributions, cash, securities, instruments and other
property or proceeds of any kind to which Debtor may be entitled in its capacity
as an owner of Equity Interests in the Company by way of distribution, return of
capital or otherwise;

(v) any other claim which Debtor now has or may in the future acquire in its
capacity as an owner of Equity Interests in the Company against the Company and
its property; and

(vi) all proceeds, products and accessions of and to any of the property
described in the preceding clauses (i) through (v).

                                       1