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                                                                     EXHIBIT 4.2



                              Calpine Corporation

                      4% Convertible Senior Notes due 2006



                         REGISTRATION RIGHTS AGREEMENT
                         -----------------------------



                                                             December 26, 2001



Deutsche Bank Alex. Brown Inc.
31 West 52nd Street
New York, New York, 10019

Dear Sirs:

     Calpine Corporation, a Delaware corporation (the "Company"), proposes to
issue and sell (the "Initial Placement") to Deutsche Bank Alex. Brown Inc. (the
"Purchaser") upon the terms set forth in the Purchase Agreement dated December
20, 2001 (the "Purchase Agreement"), among the Purchaser and the Company, up to
$1,000,000,000 (or up to $1,200,000,000 to the extent the option granted to
purchase additional Securities (as defined below) by the Company to the
Purchaser pursuant to the Purchase Agreement is exercised in full) of its 4%
Convertible Senior Notes Due 2006 (the "Securities"). As an inducement to the
Purchaser to enter into the Purchase Agreement and in satisfaction of a
condition to the obligations of the Purchaser thereunder, the Company agrees
with the Purchaser for the benefit of the Holders (as defined herein), as
follows:

     1.   DEFINITIONS. Capitalized terms used herein without definition shall
have the meanings ascribed to them in the Purchase Agreement or, if not defined
therein, in the Offering Circular dated December 20, 2001. As used in this
Agreement, the following capitalized defined terms shall have the following
meanings:

          "Act" or "Securities Act" means the Securities Act of 1933, as
amended, and the rules and regulations of the Commission promulgated thereunder.
<PAGE>
          "Affiliate" of any specified person means any other person which,
directly or indirectly, is control of, controlled by, or is under common
control with, such specified person. For purposes of this definition, control
of a person means the power, direct or indirect, to direct or cause the
direction of the management and policies of such person whether by contract or
otherwise; the terms "controlling" and "controlled" have meanings correlative
to the foregoing.

          "Applicable Rate" means the rate at which the Securities accrue
interest.

          "Business Day" means any day other than (i) a Saturday or Sunday,
(ii) a day on which banking institutions in The City of New York are authorized
or required by law to close or (iii) a day on which the corporate trust office
of the Trustee is closed for business.

          "Closing Date" has the meaning given such term in the Purchase
Agreement.

          "Commission" means the United States Securities and Exchange
Commission, or any other federal agency at the time administering the Exchange
Act or the Securities Act, whichever is the relevant statute for the particular
purpose.

          "Common Stock" means the company's common stock, par value $.001 per
share.

          "Company" has the meaning set forth in the first paragraph of this
Agreement.

          "Effectiveness Deadline" means the 180th day following  the Closing
Date.

          "Exchange Act" means the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated thereunder.

          "Filing Deadline" means the 100th day following the Closing Date.

          "Holder" and "Holders" each mean any person that is the record owner
of Registrable securities (and includes any person that has a beneficial
interest in any Registrable Security in book-entry form).

          "Indenture" means the Indenture, dated August 10, 2000, between the
Company and the Trustee, as amended and supplemented from time to time in
accordance with its terms.



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<PAGE>

          "Initial Placement" has the meaning set forth in the first paragraph
to this Agreement.

          "Managing Underwriters" means the investment banker or investment
bankers and manager or managers that shall administer an underwritten offering,
if any, as set forth in Section 6 hereof.

          "Notice and Questionnaire" means a Notice of Registration Statement
and Selling Securityholder Questionnaire in a form reasonably agreed to by the
Company and the Purchaser.

          "Person" means any individual, partnership, corporation, trust, or
unincorporated organization, or a governmental agency or political subdivision
thereof.

          "Prospectus" means the prospectus included in any Shelf Registration
Statement (including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A under the Act), with respect
to the terms of the offering of any portion of the Securities covered by such
Shelf Registration Statement, as amended or supplemented by all amendments
(including post-effective amendments) and supplements to the Prospectus.

          "Purchase Agreement" has the meaning set forth in the first paragraph
to this Agreement.

          "Purchaser" has the meaning set forth in the first paragraph to this
Agreement.

          "Registrable Securities" has the meaning specified in the Indenture.

          "Registration Default" has the meaning given to such term in Section
7(a) hereof.

          "Securities" has the meaning set forth in the first paragraph to this
Agreement.

          "Shelf Registration" means a registration effected pursuant to
Section 2 hereof.

          "Shelf Registration Period" has the meaning set forth in Section 2(b)
hereof.

          "Shelf Registration Statement" shall mean a "shelf" registration
statement filed under the Securities Act on an appropriate form providing for
the registration of, and the sale on a continuous or delayed basis by the
Holders of, all of the Registrable Securities.



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<PAGE>
pursuant to Rule 415 under the Securities Act and/or any similar rule that may
be adopted by the Commission, filed by the Company pursuant to the provisions of
Section 2 of this Agreement, including the Prospectus contained therein, any
amendments and supplements to such registration statement, including
post-effective amendments, and all exhibits and all material incorporated by
reference in such registration statements.

           "Suspension Period" has the meaning set forth in Section 7(b) hereof.

           "Trust Indenture Act" means the Trust Indenture Act of 1939, or any
successor thereto, and the rules, regulations and forms promulgated thereunder,
as the same shall be amended from time to time.

           "Trustee" means Wilmington Trust Company, in its capacity as trustee
pursuant to the Indenture.

            "Underwriter" means any underwriter of Registrable Securities in
connection with an offering thereof under a Shelf Registration Statement.

      2.    SHELF REGISTRATION. (a) The Company shall as promptly as
practicable prepare and not later than the Filing Deadline, shall file with the
Commission a Shelf Registration Statement relating to the offer and sale of
the Registrable Securities by the Holders from time to time in accordance with
the methods of distribution elected by such Holders and set forth in such Shelf
Registration Statement and, thereafter shall use its best efforts to cause such
Shelf Registration Statement to be declared effective under the Act as soon as
practicable, but in no event later than the Effectiveness Deadline; provided,
however, that the Company may, upon written notice to all Holders, postpone
having the Shelf Registration Statement declared effective for a reasonable
period not to exceed 90 days if the Company possesses material non-public
information, the disclosure of which would have a material adverse effect on
the Company and its subsidiaries taken as a whole provided, further, however,
that no Holder (other than the Purchaser) shall be entitled to have its
Registrable Securities held by it covered by such Shelf Registration Statement
unless such Holder agrees in writing to be bound by all the provisions of this
Agreement applicable to such Holder.

            (b)  The Company shall each use its best efforts:

                 (i) to keep the Shelf Registration Statements continuously
            effective in order to permit the Prospectus forming a part thereof
            to be lawfully delivered to the Holders until the earliest of (a)
            the sale of all Registrable Securities registered under the Shelf
            Registration Statement and (b) two years from the date (the
            "Effective Date") such Shelf Registration Statement is declared
            effective (or for such other period as shall be


                                       4


<PAGE>
           required by Rule 144(k) of the Act or any successor provision
           thereto), in any such case, such period being called the "Shelf
           Registration Period;" and

                     (ii)   during the Shelf Registration Period, promptly upon
           the request of any Holder of Registrable Securities, to take any
           action reasonably necessary to enable such Holder to use the
           Prospectus forming a part thereof for resales of Registrable
           Securities, and to identify such Holder as a selling securityholder;
           provided, however, that nothing in this subparagraph shall relieve
           such Holder of the obligation to return a completed and signed Notice
           and Questionnaire to the Company in accordance with Section 3(a)
           hereof.

           The Company shall be deemed not to have used its best efforts to keep
the Shelf Registration Statement effective during the Shelf Registration Period
if it voluntarily takes any action that would result in Holders of Registrable
Securities covered thereby not being able to offer and sell such Registrable
Securities during such period, unless such action is required by applicable law.

           (c)       The Company may suspend the use of the Prospectus for a
period not to exceed 30 days in any 90-day period or an aggregate of 90 days in
any 12-month period of the Board of Directors of the Company shall have
determined in good faith that because of valid business reasons (not including
the avoidance of the Company's obligations hereunder), including the acquisition
of divestiture of assets, pending corporate developments and similar events, it
is in the best interests of the Company to suspend such use, and prior to
suspending such use, the Company provides the Holders with written notice of
such suspension, which notice need not specify the nature of the event giving
rise to such suspension.

          (d)        Notwithstanding any provisions of this Agreement to the
contrary, the Company shall cause the Shelf Registration Statement and the
related Prospectus and any amendment or supplement thereto, as of the effective
date of the Shelf Registration Statement, amendment or supplement, (i) to comply
in all material respects with the applicable requirements of the Securities Act
and the rules and regulations of the Commission and (ii) not to contain any
untrue statement of a material fact or omit to state a material fact required to
be stated therein or necessary in order to make the statements therein, in light
of the circumstances under which they were made, not misleading.

     3.   REGISTRATION PROCEDURES. In connection with any Shelf Registration
Statement, the following provisions shall apply:

          (a)      (1) Not less than 30 calendar days prior to the Effective
Date of the Shelf Registration Statement, the Company shall mail the Notice and
Questionnaire to the Holders of Registrable Securities. No Holder shall be
entitled to be named as a selling

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<PAGE>
securityholder in the Shelf Registration Statement or have its Registrable
Securities included therein, and no Holder shall be entitled to use the
Prospectus forming a part thereof for resales of Registrable Securities at any
time, unless such Holder is an Electing Holder; provided, however, Holders of
Registrable Securities shall have at least 28 calendar days from the date on
which the Notice and Questionnaire is first mailed to such Holders to return a
completed and signed Notice and Questionnaire to the Company.

                     (ii)   After the Effective Date of the Shelf Registration
Statement and during the Shelf Registration Period, the Company shall, upon the
request of any Holder of Registrable Securities that is not then an Electing
Holder, promptly send a Notice and Questionnaire to such Holder. The Company
shall not be required to take any action to name such Holder as a selling
securityholder in the Shelf Registration Statement or to enable such Holder to
use the Prospectus forming a part thereof for resales of Registrable Securities
until such Holder has returned a completed and signed Notice and Questionnaire
to the Company.

                     (iii)  The term "Electing Holder" shall mean any Holder of
Registrable Securities that has returned a completed and signed Notice and
Questionnaire to the Company in accordance with Section 3(a)(i) or 3(a)(ii)
hereof and has otherwise agreed to be bound by all the provisions of this
Agreement applicable to such Holder.

           (b)        The Company shall furnish to (i) the Purchaser and (ii)
any other Holders who so request, and its counsel and accountants, prior to the
filing thereof with the Commission, a copy of any shelf Registration Statement,
and each amendment thereof and each amendment or supplement, if any, to the
Prospectus included therein and shall each use its best efforts to reflect in
each such document, when so filed with the Commission, such comments as the
Purchaser and such other Holders reasonably may propose.

           (c)        The Company shall give written notice to the Purchaser
and the Holders:

                      (i)   when the Shelf Registration Statement and any
           amendment thereto has been filed with the Commission and when
           the Shelf Registration Statement or any post-effective amendment
           thereto has become effective.

                      (ii)  of any written request by the Commission for
           amendments or supplements to the Shelf Registration Statement
           or the Prospectus included therein or for additional information;

                      (iii) of the issuance by the Commission of any stop
           order suspending the effectiveness of the Shelf Registration
           Statement or the initiation of any proceeding for that purpose;


                                       6

<PAGE>
                (iv)   of the receipt by the Company of any notification with
           respect to the suspension of the qualification of the Securities
           included therein for sale in any state or the initiation or
           threatening of any proceeding for such purpose; and

                (v)    of the happening, during the Shelf Registration Period
           of any event that requires the making of any changes in the Shelf
           Registration Statement or the Prospectus so that, as of such date,
           the Registration Statement and the Prospectus do not contain an
           untrue statement of a material fact and do not omit to state a
           material fact required to be stated therein or necessary to make the
           statements therein (in the case of the Prospectus, in light of the
           circumstances under which they were made) not misleading (which
           advice shall be accompanied by an instruction to suspend the use of
           the Prospectus until the requisite changes have been made).

           (d)  The Company shall use its best efforts to prevent the issuance,
and if issued to obtain the withdrawal, of any order suspending the
effectiveness of any Shelf Registration Statement at the earliest possible time.

           (e)  The Company shall furnish to the Purchaser and each requesting
Holder included within the coverage of any Shelf Registration Statement, without
charge, at least one copy of such Shelf Registration Statement and any
post-effective amendment thereto (including, to the Purchaser or any such Holder
who so requests, any reports or other documents incorporated therein by
reference), including financial statements and schedules included therein, and,
if such Holder so requests, all exhibits (including those incorporated by
reference).

           (f)  The Company shall, during the Shelf Registration Period,
deliver to each Holder included within the coverage of any Shelf Registration
Statement, without charge, as many copies of the Prospectus (including each
preliminary Prospectus) included in such Shelf Registration Statement and any
amendment or supplement thereto as such Holder may reasonably request; and the
Company consents to the use, in accordance with the terms of this Agreement of
the Prospectus or any amendment or supplement thereto by each of the selling
Holders of Registrable Securities in connection with the offering and sale of
the Registrable Securities covered by the Prospectus or any amendment or
supplement thereto during the Shelf Registration Period.


           (g)  Prior to any offering of Registrable Securities pursuant to any
Shelf Registration Statement, the Company shall register or qualify, or shall
cooperate with the Holders of Registrable Securities included therein and their
respective counsel in connection with the registration or qualification of,
such Registrable Securities for offer and sale under the securities or blue sky
laws of such states as any such Holders reasonably request in writing and do
any and all other acts or things necessary or advisable to enable the offer and


                                       7

<PAGE>
sale in such states of the Registrable Securities covered by such Shelf
Registration Statement; provided, however, that the Company will not be required
to qualify generally to do business in any jurisdiction where it is not then so
qualified or to take any action which would subject it to general service of
process or to taxation in any such jurisdiction where it is not then so subject.

           (h)    Unless the applicable Registrable Securities shall be in
book-entry form, the Company shall cooperate with the Holders of Registrable
Securities to facilitate the timely preparation and delivery of certificates
representing Registrable Securities to be sold pursuant to any Shelf
Registration Statement free of any restrictive legends and in such permitted
denominations and registered in such names as Holders may request in connection
with the sale of Registrable Securities pursuant to such Shelf Registration
Statement.

           (i)    Upon the occurrence of any event contemplated by paragraphs
(ii) through (v) of Section 3(b) above (other than a request by the Commission
solely for additional information as referred to in Section 3(b)(ii) and unless
directed otherwise by the Commission), the Company shall promptly prepare and
file a post-effective amendment to any Shelf Registration Statement or an
amendment or supplement to the related Prospectus or file any other required
document so that, as thereafter delivered to Holders or purchasers of the
Registrable Securities included therein, the Prospectus will not contain an
untrue statement of a material fact or omit to state any material fact required
to be stated therein or necessary to make the statements therein, in the light
of the circumstances under which they were made, not misleading. If the Company
notifies the Purchaser or the Holders of the Securities in accordance with
paragraphs (ii) through (v) of Section 3(b) above to suspend the use of the
Prospectus until the requisite changes to the Prospectus have been made, then
the Purchaser and the Holders of the Registrable Securities shall suspend use of
the Prospectus for such time.

           (j)    Not later than the effective date of any Shelf Registration
Statement hereunder, the Company shall provide a CUSIP number for the
Registrable Securities registered under such Shelf Registration Statement, and
provide the applicable Trustee with certificates for such Registrable
Securities, in a form eligible for deposit with The Depository Trust Company.

           (k)    The Company shall use its best efforts to comply with all
applicable rules and regulations of the Commission and shall make generally
available to its security holders (or otherwise provide in accordance with
Section 11(a) of the Securities Act) as soon as practicable after the
effective date of the applicable Shelf Registration Statement an earning
statement satisfying the provisions of Section 11(a) of the Securities Act,
but in no event later than 45 days after the end of a 12-month period (or 90
days, if such period is a fiscal year) beginning with the first month of the
Company's first fiscal quarter commencing


                                       8
<PAGE>
after the effective date of Registration Statement, which statement shall cover
such 12-month period.

           (l)    The Company shall cause the Indenture to be qualified under
the Trust Indenture Act in a timely manner and containing such changes, if any,
as shall be necessary for such qualification.  In the event that such
qualification would require the appointment of a new trustee under the
Indenture, the Company shall appoint a new trustee thereunder pursuant to the
applicable provisions of such agreement.

           (m)    The Company may require each Holder of Registrable Securities
to be sold pursuant to any Shelf Registration Statement as a condition to the
registration of such Holder's Registrable Securities thereunder to furnish to
the Company such information regarding the Holder and the distribution of such
Registrable Securities as the Company may from time to time reasonably require
for inclusion in such Shelf Registration Statement. Each Holder who offers and
sells Registrable Securities by means of the Shelf Registration Statement shall
do so in accordance with the terms thereof and the requirements of the
Securities Act.

           (n)    The Company shall, if requested, promptly incorporate in a
Prospectus supplement or post-effective amendment to a Shelf Registration
Statement, such information as the Managing Underwriters, if any, reasonably
agree should be included therein and to which the Company does not reasonably
object and shall make all required filings of such Prospectus supplement or
post-effective amendment as soon as practicable after they are notified of the
matters to be incorporated in such Prospectus supplement or post-effective
amendment.

           (o)    The Company shall enter into such customary agreements
(including underwriting agreements in customary form) to take all other
appropriate actions in order to expedite or facilitate the registration or the
disposition of the Registerable Securities, and connection therewith, if an
underwriting agreement is entered into, cause the same to contain
indemnification provisions and procedures substantially identical to those set
forth in Section 5 hereof (or such other customary provisions and procedures
acceptable to the Managing Underwriters, if any) with respect to all parties to
be indemnified pursuant to Section 5 hereof.

           (p)    The Company shall (i) make reasonably available for inspection
by the Holders of Securities to be registered thereunder, any underwriter
participating in any disposition pursuant to such Shelf Registration Statement,
and any attorney, accountant or other agent retained by such Holders or any such
underwriter, all relevant financial and other records, pertinent corporate
documents and properties of the Company and its subsidiaries as shall be
requested in connection with the discharge of their due diligence obligations;
(ii) cause the Company's officers, directors, employees and independent public
accountants and the Trustee to supply at the Company's expense all relevant
information


                                       9
<PAGE>
reasonably requested by such Holders or any such underwriter, attorney,
accountant or agent in connection with any such Shelf Registration Statement as
is customary for similar due diligence examinations; provided, however, that any
information that is designated in writing by the Company in good faith as
confidential at the time of delivery of such information shall be kept
confidential by such Holders or any such underwriter, attorney, accountant or
agent, unless such disclosure is made in connection with a court proceeding or
required by law, or such information becomes available to the public generally
or through a third party without an accompanying obligation of confidentiality;
and provided further that the foregoing inspection and information gathering
shall be coordinated on behalf of the Holders and the other parties entitled
thereto by one counsel, who shall be Skadden Arps, Slate, Meagher & Flom LLP
unless another nationally-recognized law firm with specialization in securities
laws shall be chosen by the Company; (iii) make such representations and
warranties to the Holders of Securities registered thereunder and the
underwriters, if any, in form, substance and scope as are customarily made by
the issuers to underwriters in primary underwritten offerings and covering
matters as are customarily covered in representations and warranties requested
in primary underwritten offering including, but not limited to, those set forth
in the Purchase Agreement; (iv) obtain options of counsel to the Company and
updates thereof (which counsel and opinions (in form, scope and substance) shall
be reasonably satisfactory to the Managing Underwriters, if any) addressed to
each selling Holder and the underwriters, if any, thereof and dated, in the case
of the initial opinion, the effective date of such Shelf Registration Statement
(it being agreed that the matters to be covered by such Shelf Registration
Statement (it being agreed that the matters to be covered by such opinion shall
include, without limitation, the due incorporation and good standing of the
Company and its Subsidiaries; the due authorization, execution and delivery of
the relevant agreement of the type referred to in Section 3(n) hereof; the due
authorization, execution, authentication and issuance, and the validity and
enforceability, of the applicable Securities; absence of material legal or
governmental proceedings involving the Company and its Subsidiaries; the absence
of governmental approvals required to be obtained in connection with the Shelf
Registration Statement, the offering and sale of the applicable Securities, or
any agreement of the type referred to in Section 3(n) hereof; the compliance as
to form of such Shelf Registration Statement and any documents incorporated by
reference therein and of the Indenture, with the requirements of the Securities
Act and the Trust Indenture Act; and, as of the date of the opinion and as of
the effective date of the Shelf Registration Statement or most recent
post-effective amendment hereto, as the case may be, that such counsel do not
believe that such Shelf Registration Statement and the prospectus included
therein, as then amended or supplemented, and any documents incorporated by
reference therein contain an untrue statement of a material fact or omit to
state therein a material fact required to be stated therein or necessary to the
statements therein not misleading (in the case of any such documents, in the
light of the circumstances existing at the time that such documents were filed
with the Commission under the Exchange Act); (v) cause its officers to execute
and deliver all customary documents and certificates and updates thereof
requested by such Holders and any underwriters of the applicable Securities and
(vi) cause its independent public accountants and the independent public
accountants with respect to any other entity for which financial information is


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<PAGE>
provided in the Shelf Registration Statement to provide to the Holders of the
applicable Securities and any underwriter therefor a comfort letter in customary
form and covering matters of the type customarily covered in comfort letters in
connection with primary underwritten offerings, subject to receipt of
appropriate documentation as contemplated, and only if permitted, by Statement
of Auditing Standards No. 72. The foregoing actions set forth in clauses (iii),
(iv), (v), and (vi) of this Section 3(o) shall be performed at (A) the
effectiveness of such Shelf Registration Statement and each post-effective
amendment thereto and (B) each closing under any underwritten offering of the
Securities to the extent required under any related underwriting or similar
agreement.

           (q)   The Company will use its best efforts to cause the Common Stock
issuable upon conversion of the Securities to be listed on each securities
exchange, over-the-counter market, or respective counterpart if any, on which
any shares of Common Stock are then listed.

           (r)   The Company shall, in the event that any broker-dealer
registered under the Exchange Act shall underwrite any Registerable Securities
or participate as a member of an underwriting syndicate or selling group or
"assist in the distribution" (within the meaning of the Rules of Fair Practice
and By-Laws of the National Association of Securities Dealers, Inc. ("NASD"))
thereof, whether as a Holder of such Registrable Securities or as an
underwriter, a placement or sales agent or a broker or dealer in respect
thereof, or otherwise, assist such broker-dealer in complying with the
requirements of such Rules and By-Laws, including, without limitation, by (A) if
such Rules or By-Laws, including Rule 2720, shall so require, engaging  a
"qualified independent underwriter" (as defined in Rule 2720) to participate in
the preparation of the Shelf Registration Statement relating to such Registrable
Securities, to exercise usual standards of due diligence in respect thereto and,
if any portion of the offering contemplated by such Shelf Registration Statement
is an underwritten offering or is made through a placement or sales agent, to
recommend the yield of such Registrable Securities, (B) indemnifying any such
qualified independent underwriter to the extent of the indemnification of
underwriters provided in Section 5 hereof and (C) providing such information to
such broker-dealer as may be required in order for such broker-dealer to comply
with the requirements of the Rules of Fair Practice of the NASD.

           (s)   The Company shall use its best efforts to take all other steps
necessary to effect the registration, offering and sale of the Registrable
Securities covered by the Shelf Registration Statement contemplated hereby.

   4.      REGISTRATION EXPENSES. (a) All expenses incident to the Company's
performance of and compliance with this Agreement will be borne by the
Company, regardless of whether a Shelf Registration Statement is ever filed or
becomes effective, including without limitation:


                                       11
<PAGE>
                     (i)   all registration and filing fees and expenses;

                     (ii)  all fees and expenses of compliance with federal
              securities and state "blue sky" or securities laws;

                     (iii) all expenses of printing (including, printing
              certificates for the Securities without the restrictive legend to
              be issued and printing of Prospectuses), messenger and delivery
              services and telephone.

                     (iv)  all fees and disbursements of counsel for the
              Company;

                     (v)   all application and filing fees in connection with
              listing the Securities on a national securities exchange or
              automated quotation system pursuant to the requirements hereof;
              and

                    (vi)   all fees and disbursements of independent certified
              public accountants of the Company (including the expenses of any
              special audit and comfort letters required by or incident to such
              performance).

              The Company will bear its internal expenses (including, without
limitation all salaries and expenses of its officers and employees performing
legal or accounting duties), the expenses of any annual audit and the fees and
expenses of any person, including special experts, retained by the Company.

              (b)    In connection with any Shelf Registration Statement
required by this Agreement, the Company will reimburse the Purchasers and the
Holders who are selling or reselling Registrable Securities pursuant to the
Shelf Registration Statement for the reasonable fees and disbursements of not
more than one counsel, who shall be Skadden, Arps, Slate, Meagher & Flom LLP
unless another nationally-recognized law firm with specialization in securities
laws shall be chosen by the Company.

     5.       INDEMNIFICATION AND CONTRIBUTION. (a) In connection with any Shelf
Registration Statement, the Company agrees to indemnify and hold harmless the
Purchaser, each Holder of Securities covered thereby (including the Purchaser),
their respective partners, directors, and officers and each person, if any, who
controls the Purchaser or any such Holder within the meaning of Section 15 of
the Securities Act (the Purchaser, Holder and such controlling persons are
referred to collectively as the ("Indemnified Parties") against any losses,
claims, damages or liabilities, joint or several, or any actions in respect
thereof (including, but not limited to, any losses, claims, damages, liabilities
or actions relating to purchases and sales of the Securities) to which each
Indemnified Party may become subject under the Securities Act, the Exchange Act
or other Federal or state statutory law or regulation, at common law or
otherwise, insofar as such losses, claims, damages or liabilities (or actions
in respect thereof) arise out of or are based upon any


                                       12
<PAGE>
untrue statement or alleged untrue statement of a material fact contained in the
Shelf Registration Statement as originally filed or in any amendment or
supplement thereof, or in any preliminary Prospectus or Prospectus, or in any
amendment thereof or supplement thereto, or arise out of or are based upon the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, in
the light of the circumstances under which they were made, and shall reimburse
each such Indemnified Party, as incurred, for any legal or other expenses
reasonably incurred by them in connection with investigating or defending any
such loss, claim, damage, liability or action; provided, however, that (i) the
Company will not be liable in any case to the extent that any such loss, claim,
damage or liability arises out of or is based upon any such untrue statement or
alleged untrue statement or omission or alleged omission made therein in
reliance upon and in conformity with written information furnished to the
Company by or on behalf of the Purchaser or any such Holder specifically for
inclusion therein and (ii) the foregoing indemnity, with respect to any untrue
statement or alleged untrue statement or omission or alleged omission made in
any preliminary Prospectus relating to a Shelf Registration Statement, shall not
inure to the benefit of any Holder (or any person controlling such Holder) from
whom the person asserting any such losses, claims, damages or liabilities
purchased the Securities concerned, to the extent that a Prospectus relating to
such Securities was required to be delivered by such Holder under the Securities
Act in connection with such purchase and any such loss, claim, damage or
liability of such Holder results from the fact that there was not sent or given
to such person, at or prior to the written confirmation of the sale of such
Securities to such person, a copy of the final Prospectus if the Company had
previously furnished copies thereof to such Holder at or prior to the written
confirmation of the sale of such Securities to such person and the untrue
statement or alleged untrue statement or omission or alleged omission contained
in the preliminary prospectus was corrected in the final prospectus (or the
final prospectus as supplemented). This indemnity agreement will be in addition
to any liability which the Company may otherwise have.


           The Company shall also indemnify underwriters, their officers,
directors and each person who controls such underwriters within the meaning of
the Securities Act or the Exchange Act to the same extent as provided above with
respect to the indemnification of the Holders of the Securities and shall, if
requested by any Holder, enter into an underwriting agreement reflecting such
agreement, as provided in Section 3(n) and Section 6 hereof.

           (b)    Each Holder of Securities covered by a Shelf Registration
Statement (including the Purchaser)  severally, and not jointly, agrees to
indemnify and hold harmless (i) the Company, (ii) each of the directors of the
Company, (iii) each of its officers who signs such Shelf Registration Statement
and (iv) each person who controls the Company within the meaning of either the
Securities Act or the Exchange Act to the same extent as the foregoing indemnity
from the Company, but only in respect of written information relating to such
Holder furnished to the Company by or on behalf of such Holder specifi-


                                       13
<PAGE>
cally for inclusion in the documents referred to in the foregoing indemnity.
This indemnity agreement will be in addition to any liability which any such
Holder may otherwise have.

            (c)   Promptly after receipt by an indemnified party under this
Section 5 of notice of the commencement of any action or proceeding (including a
governmental investigation), such indemnified party will, if a claim in respect
thereof is to be made against the indemnifying party under this Section 5,
notify the indemnifying party of the commencement thereof; but the omission so
to notify the indemnifying party will not relieve the indemnifying party from
any liability it may have to any indemnified party otherwise than under
paragraph (a) or (b) above. In case any such action is brought against any
indemnified party and it notifies the indemnifying party of the commencement
thereof, the indemnifying party will be entitled to participate therein and, to
the extent that it may wish, jointly with any other indemnifying party similarly
notified, to assume the defense thereof, with counsel reasonably satisfactory to
such indemnified party (who shall not, except with the consent of such
indemnified party, be counsel to the indemnifying party), and after notice from
the indemnifying party to such indemnified party of its election so to assume
the defense thereof, the indemnifying party will not be liable to such
indemnified party under this Section 5 for any legal or other expenses
subsequently incurred by such indemnified party in connection with the defense
thereof other than reasonable costs of investigation. No indemnifying party
shall, without the prior written consent of the indemnified party, effect any
settlement of any pending or threatened action in respect of which any
indemnified party is or could have been a party and indemnity could have been
sought hereunder by such indemnified party unless such settlement includes an
unconditional release of such indemnified party from all liability on any claims
that are the subject matter of such action and does not include a statement as
to or an admission of fault, culpability or a failure to act by or on behalf of
any indemnified party.

            (d)   If the indemnification provided for in this Section 5 is
unavailable or insufficient to hold harmless an indemnified party under
subsections (a) or (b) above, then each indemnifying party shall contribute to
the amount paid or payable by such indemnified party as a result of the losses,
claims, damages or liabilities (or actions in respect thereof) referred to in
subsection (a) or (b) above (i) in such proportion as is appropriate to reflect
the relative benefits received by the indemnifying party or parties on the one
hand and the indemnified party on the other from the Initial Placement and the
Shelf Registration Statement, or (ii) if the allocation provided by the
foregoing clause (i) is not permitted by applicable law, in such proportion as
is appropriate to reflect not only the relative benefits referred to in clause
(i) above but also the relative fault of the indemnifying party or parties on
the one hand and the indemnified party on the other in connection with the
statements or omissions that resulted in such losses, claims, damages or
liabilities (or actions in respect thereof) as well as any other relevant
equitable considerations. The relative fault of the parties shall be determined
by reference to, among other things, whether the untrue or alleged untrue
statement of a material fact or the omission or alleged omission to state a
material fact relates to information supplied by the Company on the one hand or


                                       14

<PAGE>
such Holder or such other indemnified party, as the case may be, on the other,
and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission. The amount paid by
an indemnified party as a result of the losses, claims, damages or liabilities
referred to in the first sentence of this subsection (d) shall be deemed to
include any legal or other expenses reasonably incurred by such indemnified
party in connection with investigating or defending any action or claim which is
the subject of this subsection (d). Notwithstanding any other provision of this
Section 5(d), the Holders of the Securities shall not be required to contribute
any amount in excess of the amount by which the net proceeds received by such
Holders from the sale of the Securities pursuant to the Shelf Registration
Statement exceeds the amount of damages which such Holders have otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. For purposes of this paragraph (d), each person, if any, who
controls such indemnified party within the meaning of the Securities Act or the
Exchange Act shall have the same rights to contribution as such indemnified
party and each person, if any, who controls the Company within the meaning of
the Securities Act or the Exchange Act shall have the same rights to
contribution as the Company.

            (e)   The agreements contained in this Section 5 shall survive the
sale of the Securities pursuant to a Registration Statement and shall remain in
full force and effect, regardless of any termination or cancellation of this
Agreement or any investigation made by or on behalf of any indemnified party.

      6.    UNDERWRITTEN OFFERING. If, pursuant to written notice delivered to
the Company by the Holders of a majority of aggregate principal amount of
Registrable Securities then registered pursuant to a Shelf Registration, such
Holders so elect, the offer and sale of any such Common Stock may be effected in
the form of an underwritten offering. In any such underwritten offering, the
investment banker or bankers and manager or managers that will administer the
offering will be selected by, and the underwriting arrangements with respect
thereto will be approved by, the Company; provided, however, that such
investment bankers and managers and underwriting arrangements must be reasonably
satisfactory to the Holders of a majority of the Registrable Securities to be
included in such offering. No Holder may participate in any underwritten
offering contemplated hereby unless such Holder (a) agrees to sell such Holder's
Registrable Securities in accordance with any approved underwriting
arrangements, and (b) completes and executes all reasonable questionnaires,
powers of attorney, indemnities, underwriting agreements, lock-up letters and
other documents required under the terms of such approved underwriting
arrangements.

      7.    CHANGES TO THE APPLICABLE RATE UNDER CERTAIN CIRCUMSTANCES. (a)
Pursuant to Section 2(a) hereof, the Company, may, upon written notice to all
the Holders,


                                       15
<PAGE>
postpone having the Shelf Registration Statement declared effective for a
reasonable period not to exceed 90 days if the Company possesses material
non-public information, the disclosure of which would have a material adverse
effect on the Company and its subsidiaries taken as a whole. Notwithstanding any
such postponement, the Applicable Rate shall be adjusted as follows, if any of
the following events occur (each such event in clauses (i) through (iii) below,
a "Registration Default"):

                  (i)     if a Shelf Registration Statement has not been filed
            with the Commission on or prior to the Filing Deadline;

                  (ii)    if the Shelf Registration Statement has not been
            declared effective by the Commission on or prior to the
            Effectiveness Deadline;

                  (iii)   if (A) after the Shelf Registration Statement is
            declared effective, such Shelf Registration Statement ceases to be
            effective prior to the earlier of (1) the end of the Shelf
            Registration Period, (2) the sale of all Registrable Securities
            registered under the Shelf Registration Statement or (3) the
            expiration of the applicable period under Rule 144(k) of the
            Securities Act or (B) such Shelf Registration Statement or the
            related Prospectus ceases to be usable (including if the use of the
            Prospectus is suspended by the Company for more than 30 days in any
            90-day period or an aggregate of 90 days in any 12-month period, as
            set forth in Section 2(c) hereof) in connection with resales of
            Securities covered by such Shelf Registration Statement prior to the
            end of the Shelf Registration Period because either (1) any event
            occurs as a result of which the related Prospectus forming part of
            such Shelf Registration Statement would include any untrue statement
            of a material fact or omit to state any material fact necessary to
            make the statements therein in the light of the circumstances in
            which they were made not misleading or (2) it shall be necessary to
            amend such Shelf Registration Statement, or supplement the related
            Prospectus, to comply with the Securities Act or the Exchange Act or
            the respective rules thereunder.

            Each of the foregoing will constitute a Registration Default
whatever the reason for any such event and whether it is voluntary or
involuntary or is beyond the control of the Company or pursuant to operation of
law or as a result of any action or inaction by the Commission.

            Additional interest shall accrue on the Registrable Securities over
and above the interest set forth in the title of the Registrable Securities from
and including the date on which any such Registration Default shall occur to but
excluding the date on which all such Registration Defaults have been cured, at a
rate of 0.50% per annum (the "Additional Interest Rate"). The increase in the
Applicable Rate attributable to any Registration Default shall cease to be
effective from the date such Registration Default is cured, and the Applica-


                                       16
<PAGE>
ble Rate shall be reduced at such time to the Applicable Rate in effect
immediately prior to such Registration Default.

            (b)   A Registration Default referred to in Section 7(a)(iii) shall
be deemed not to have occurred and be continuing in relation to the Shelf
Registration Statement or the related Prospectus if (i) such Registration
Default has occurred solely as a result of (x) the filing of a post-effective
amendment to such Shelf Registration Statement to incorporate annual audited
financial information with respect to the Company where such post-effective
amendment is not yet effective and needs to be declared effective to permit
Holders to use the related Prospectus or (y) the occurrence of other material
events or developments with respect to the Company that would need to be
described in such Registration Statement or the related Prospectus and (ii) in
the case of clause (y) the Company is proceeding promptly and in good faith to
amend or supplement such Registration Statement and related Prospectus to
describe such events; provided, however, that in any case if such Registration
Default occurs for a continuous period in excess of 30 days in any 90-day period
or an aggregate of 90 days in any 12-month period, Additional Interest shall be
payable in accordance with the above paragraph from the day such Registration
Default occurred until such Registration Default is cured.

            (c)   Any amounts of Additional Interest due pursuant to Section
7(a) will be payable in cash on the regular interest payment dates (or such
other time as provided in the Indenture for the payment of interest or
distributions) with respect to the Securities. The amount of Additional Interest
will be determined by multiplying the applicable Additional Interest Rate by the
principal amount of the Registrable Securities and further multiplied by a
fraction, the numerator of which is the number of days such Additional Interest
Rate was applicable during such period (determined on the basis of a 360-day
year comprised of twelve 30-day months), and the denominator of which is 360.

      8.    RULES 144 AND 144A. The Company shall use its best efforts to file
the reports required to be filed by it under the Securities Act and the Exchange
Act in a timely manner and, if at any time the Company is not required to file
such reports, it will, upon the request of any Holder of Registrable Securities,
make publicly available other information so long as necessary to permit sales
of their securities pursuant to Rules 144 and 144A of the Securities Act, or any
successor regulation or stature thereto. The Company covenants that it will take
such further action as any Holder may reasonably request, all to the extent
required from time to time to enable such Holder to sell Securities without
registration under the Securities Act within the limitation of the exemptions
provided by Rules 144 and 144A (including the requirements of Rule 144A(d)(4)).
The Company will provide a copy of this Agreement to prospective purchasers of
Securities identified to the Company by the Purchasers upon request. Upon the
request of any Holder of Securities, the Company shall deliver to such Holder a
written statement as to whether it has complied with such requirements.
Notwithstanding the foregoing, nothing in this Section 8 shall be deemed to
require the Company to register any of its securities pursuant to the Exchange
Act.


                                       17
<PAGE>
      9.    MISCELLANEOUS.

            (a)   Remedies. The Company acknowledges and agrees that any failure
by it to comply with its obligations under Section 2 hereof may result in
material irreparable injury to the Purchasers or the Holders for which there is
no adequate remedy at law, that it will not be possible to measure damages for
such injuries precisely and that, in the event of any such failure, the
Purchasers or any Holder may obtain such relief as may be required to
specifically enforce the Company's obligations under Section 2 hereof. The
Company further agrees to waive the defense in any action for specific
performance of Section 2 hereof that a remedy at law would be adequate.

            (b)   No Inconsistent Agreements. The Company has not, as of the
date hereof, entered into, nor shall it on or after the date hereof, enter into,
any agreement with respect to its securities or otherwise that is inconsistent
with the rights granted to the Holders herein or otherwise conflicts with the
provisions hereof.

            (c)   Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, qualified,
modified or supplemented, and waivers or consents to departures from the
provisions hereof may not be given, unless the Company has obtained the written
consent of a majority in principal amount of the Registrable Securities affected
by such amendment, qualification, modification, supplement, waiver or consent.

            (d)   Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing and shall be mailed, delivered,
telegraphed and confirmed or faxed and confirmed:

            (1)   if to a Holder, at the most current address given by such
      Holder to the Company in accordance with the provisions of this Section
      9(d), which address initially is, with respect to each Holder, the address
      of such Holder maintained by the Registrar under the Indenture; with a
      copy in a like manner to Deutsche Bank Alex. Brown Inc.;

            (2)   if to the Purchaser, initially at the address set forth in the
      Purchase Agreement; and

            (3)   if to the Company, initially at its address set forth in the
      Purchase Agreement.

            The Purchaser, any Holder or the Company by notice to the other may
designate additional or different addresses for subsequent notices or
communications.


                                       18
<PAGE>
            (e)   Third Party Beneficiaries. The Holders shall be third party
beneficiaries to the agreements made hereunder between the Company, on the one
hand, and the Purchaser, on the other hand, and shall have the right to enforce
such agreements directly to the extent they may deem such enforcement necessary
or advisable to protect their rights or the rights of Holders hereunder.

            (f)   Successors and Assigns. This Agreement shall inure to the
benefit of and be binding upon the successors and assigns of each of the parties
and the Holders, including, without the need for an express assignment or any
consent by the Company thereto, subsequent Holders of Securities. The Company
hereby agrees to extend the benefits of this Agreement to any Holder of
Registrable Securities and any such Holder may specifically enforce the
provisions of this Agreement as if an original party hereto.

            (g)   Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

            (h)  Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

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

            (j)   Securities Held by the Company. Whenever the consent or
approval of Holders of a specified percentage of principal amount of Securities
is required hereunder, Securities held by the Company or its affiliates (other
than subsequent Holders of Securities if such subsequent Holders are deemed to
be affiliates solely by reason of their holdings of such Securities) shall not
be considered to be outstanding and shall not be counted in determining whether
such consent or approval was given by the Holders of such required percentage.

            (k)   Severability. In the event that any one of more of the
provisions contained herein, or the application thereof in any circumstances, is
held invalid, illegal or unenforceable in any respect for any reason, the
validity, legality and enforceability of any such provision in every other
respect and of the remaining provisions hereof shall not be in any way impaired
or affected thereby, it being intended that all of the rights and privileges of
the parties shall be enforceable to the fullest extent permitted by law.

                           (Signature page follows.)


                                       19
<PAGE>


                     Please confirm that the foregoing correctly sets forth the
agreement between the Company and the Purchaser.



                                     Very truly yours,


                                     CALPINE CORPORATION


                                     By: /s/ ROBERT D. KELLY
                                        ----------------------------------
                                     Name:   Robert D. Kelly
                                     Title:  Senior Vice President-Finance



                     The foregoing Registration Rights Agreement is hereby
confirmed and accepted as of the date first above written.


DEUTSCHE BANC ALEX. BROWN INC.


By:
   ---------------------------
Name:
Title:
<PAGE>
                     Please confirm that the foregoing correctly sets forth the
agreement between the Company and the Purchaser.


                                  Very truly yours,


                                  CALPINE CORPORATION


                                  By:
                                     -------------------------
                                  Name:
                                  Title:



                     The foregoing Registration Rights Agreement is hereby
confirmed and accepted as of the date first above written.


DEUTSCHE BANC ALEX. BROWNE INC.


By: /s/ ANTONY T F LUNDY
   ----------------------------
Name:   Antony T F Lundy
Title:  Managing Director


By: /s/ GEORGE ORDONEZ
   ----------------------------
Name:   George Ordonez
TITLE:  Director