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                                                                    Exhibit 99.1

[Calpine Logo]



NEWS RELEASE                                           CONTACTS: (408) 995-5115
                                  Media Relations:  Katherine Potter, Ext. 1168
                                   Investor Relations:  Karen Bunton, Ext. 1121


     CALPINE ANNOUNCES OFFER TO PURCHASE FOR CASH ANY AND ALL OUTSTANDING
             9-5/8% FIRST PRIORITY SENIOR SECURED NOTES DUE 2014

        (SAN JOSE, Calif.) /PR Newswire - First Call/ June 9, 2005 - Calpine
Corporation [NYSE: CPN] announced today the commencement of a tender offer (the
"Offer") to purchase for cash any and all of the outstanding 9-5/8% First
Priority Senior Secured Notes due 2014 (the "Notes").  The aggregate principal
amount of the outstanding Notes is currently $785,000,000.  The Offer is being
made pursuant to the terms of the Indenture, dated as of September 30, 2004
(the "Indenture"), between the Company and Wilmington Trust Company, as
Trustee, pursuant to which the Notes were issued.

        Subject to the terms and conditions of the Offer, the consideration for
the Notes validly tendered pursuant to the Offer on or prior to 12:00 midnight,
New York City time, on the Expiration Date (as defined below) (the "Offer
Consideration") shall be $1,000 per $1,000 principal amount of Notes validly
tendered and not validly withdrawn, plus accrued and unpaid interest up to, and
including, the Purchase Date.  The "Purchase Date" is the date, not later than
the third business day following the Expiration Date, on which Calpine accepts
for purchase, pursuant to the terms and conditions of the Offer, Notes validly
tendered (and not validly withdrawn) in the Offer.

        The Offer is scheduled to expire at 12:00 midnight, New York City Time,
on July 8, 2005, unless extended or earlier terminated (the "Expiration Date").
Tendered Notes may be withdrawn at any time prior to 12:00 midnight, New York
City Time, on the Expiration Date.

        The Company has recently commenced a process with potential buyers to
dispose of its remaining U.S. gas assets (the "Gas Divestiture").  The
consummation of the Gas Divestiture would qualify as an "Asset Sale" under the
Indenture and would require the Company to make an offer to purchase the Notes
pursuant to the Indenture with the net proceeds of the Gas Divestiture not
applied in accordance with the other permitted uses under the Indenture.
Calpine is making the Offer to comply with its obligations under the Indenture
and in order to avail itself of the opportunity to reduce its indebtedness by
applying the proceeds of the Gas Divestiture to the purchase of the Notes.
Accordingly the Offer is being made in compliance with the Indenture's
requirements applicable to repurchases and repayment of the Notes using the
proceeds of "Asset Sales" such as the contemplated Gas Divestiture.

                                   - more -

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Calpine Announces Offer to Purchase for Cash Any and All Outstanding
9-5/8% First Priority Senior Secured Notes due 2014
Page 2
June 9, 2005


        Although the Company expects to consummate the Gas Divestiture on or
prior to the Purchase Date, the Company has not yet entered into definitive
documentation related to the Gas Divestiture and there can be no assurance that
the Company (i) will be able to do so by such date, or at all, or be able to do
so on terms acceptable to the Company or (ii) will not make a determination to
abandon the Gas Divestiture.  In such event, Calpine may, among other things,
extend or otherwise amend or terminate the Offer.

        Following the completion of the Offer, the Company currently
anticipates using any net proceeds arising from the proposed Gas Divestiture
remaining after consummation of the Offer (regardless of the aggregate
principal amount of Notes purchased in the Offer, if any) to acquire new
"Designated Assets" permitted to be acquired under the Indenture.  The Company
is not required to acquire new Designated Assets under the Indenture and there
can be no assurance that the Company will be successful in identifying new
Designated Assets or acquiring such new Designated Assets on acceptable terms,
or at all.  If the Company does not, within 180 days of receipt of the net
proceeds from the proposed Gas Divestiture, acquire such new Designated Assets,
or does not, at the Company's option, use all of the net proceeds arising from
the proposed Gas Divestiture remaining after consummation of the Offer in the
purchase, redemption or prepayment of Notes remaining outstanding after
consummation of the Offer, then the Company will, to the extent that the
remaining net proceeds exceed $50,000,000, be required under the terms of its
second lien secured financing documents to use all remaining net proceeds to
make an offer to purchase the outstanding second lien secured indebtedness of
the Company.  As of March 31, 2005, the aggregate principal amount of the
outstanding second lien secured indebtedness of the Company was approximately
$3,681,250,000.

        This press release is not an offer to purchase or a solicitation of an
offer to sell any securities, which is being made only pursuant to the Offer to
Purchase, dated June 9, 2005.  Calpine has retained Merrill Lynch & Co. to
serve as Dealer Manager, The Bank of New York to serve as the Tender Agent and
MacKenzie Partners, Inc. to serve as Information Agent for the Tender Offer.
The means to tender Notes may be obtained by requesting the Offer to Purchase,
the Letter of Transmittal and other documents from MacKenzie Partners, Inc. at
(800) 322-2885 or by calling (212) 929-5500 collect or in writing at 105
Madison Avenue, New York, New York 10016.  Questions regarding the Offer may be
directed to Merrill Lynch & Co., Attn: Liability Management Group, at (888)
654-8637 or by calling (212) 449-4914 collect.



                                   - more -


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Calpine Announces Offer to Purchase for Cash Any and All Outstanding
9-5/8% First Priority Senior Secured Notes due 2014
Page 3
June 9, 2005


        None of Calpine, the Dealer Manager, the Tender Agent or the
Information Agent makes any recommendation as to whether or not holders of
Notes should tender their Notes pursuant to the Offer.  Holders must make their
own decision as to whether to tender their Notes, and if tendering, the
principal amount of Notes to tender.  In any jurisdiction where the laws
require the Offer to be made by a licensed broker or dealer, the Offer will be
deemed made on behalf of Calpine by Merrill Lynch & Co., or one or more
registered brokers or dealers under the laws of such jurisdiction.

        A major power company, Calpine Corporation supplies customers and
communities with electricity from clean, efficient, natural gas-fired and
geothermal power plants. Calpine owns, leases and operates integrated systems
of plants in 21 U.S. states, three Canadian provinces and in the United
Kingdom. Its customized products and services include wholesale and retail
electricity, natural gas, gas turbine components and services, energy
management, and a wide range of power plant engineering, construction and
operations services. Calpine was founded in 1984. It is included in the S&P 500
Index and is publicly traded on the New York Stock Exchange under the symbol
CPN. For more information, visit http://www.calpine.com.

        This news release discusses certain matters that may be considered
"forward-looking" statements within the meaning of Section 27A of the
Securities Act of 1933, as amended, and Section 21E of the Securities Exchange
Act of 1934, as amended, including statements regarding the intent, belief or
current expectations of Calpine Corporation ("the Company") and its management.
Prospective investors are cautioned that any such forward-looking statements
are not guarantees of future performance and involve a number of risks and
uncertainties that could materially affect actual results.  Such risks include,
but are not limited to, those risks identified from time-to-time in the
Company's reports and registration statements filed with the SEC, including the
risk factors identified in its Annual Report on Form 10-K for the year ended
December 31, 2004 and in its Quarterly Report on Form 10-Q for the quarter
ended March 31, 2005, which can be found on the Company's website at
www.calpine.com. All information set forth in this news release is as of
today's date, and the Company undertakes no duty to update this information.

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