UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT

                       Pursuant to Section 13 or 15(d) of
                       the Securities Exchange Act of 1934


      Date of Report (Date of earliest event reported): April 29, 2005


                               CALPINE CORPORATION
             (Exact name of registrant as specified in its charter)

                                    Delaware
                 (State of Other Jurisdiction of Incorporation)

                        Commission file number: 001-12079

                  I.R.S. Employer Identification No. 77-0212977

                           50 West San Fernando Street
                           San Jose, California 95113
                            Telephone: (408) 995-5115
         (Address of principal executive offices and telephone number)

     Check the  appropriate  box below if the Form 8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions:

     [ ]  Written communications pursuant to Rule 425 under the Securities Act
          (17 CFR 230.425)

     [ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act
          (17 CFR 240.14a-12)

     [ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
          Exchange Act (17 CFR 240.14d-2(b))

     [ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
          Exchange Act (17 CFR 240.13e-4(c))




                                TABLE OF CONTENTS

ITEM 2.02 -- RESULTS OF OPERATIONS AND FINANCIAL CONDITION
SIGNATURES
EXHIBIT INDEX
EXHIBIT I

ITEM 2.02 -- RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On April 29, 2005, the Registrant  issued the press release  attached  hereto as
Exhibit I, providing a first quarter 2005 update.

                                   SIGNATURES

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.

                                  CALPINE CORPORATION

                                  By:  /s/ Charles B. Clark, Jr.
                                       ------------------------------------
                                       Charles B. Clark, Jr.
                                       Senior Vice President, Controller and
                                       Chief Accounting Officer


Date: April 29, 2005





                                  EXHIBIT INDEX


                         Exhibit                  Description
                         -------          -----------------------------
                         I                Press release


EXHIBIT I

NEWS RELEASE                                            CONTACTS: (408) 995-5115
                                     Media Relations: Bill Highlander, Ext. 1244
                                     Investor Relations: Karen Bunton, Ext. 1121


              Calpine Announces First Quarter 2005 Financial Update

           EBITDA, Earnings and Cash In-Line With Company Expectations

     (SAN JOSE,  Calif.)  /PR  Newswire - First  Call/  April 29, 2005 - Calpine
Corporation  [NYSE:CPN] is providing an estimate of key financial highlights for
the three months ended March 31, 2005. These  preliminary  results are unaudited
and  subject to final  adjustments.  Further  details  will be  provided  in the
company's first quarter  earnings  conference call scheduled for May 5, 2005, at
8:30 a.m. Pacific Daylight Time.

     "Calpine is providing  this update to assure  investors  that first quarter
financial results were in-line with our expectations and that we remain on track
to achieve our 2005 earnings," stated Calpine Chief Financial Officer Bob Kelly.

     "While  preliminary,  we believe this update is necessary  given the recent
equity and bond trading  volatility  triggered by false rumors in the market. It
is regrettable that reckless and unfounded rumors continue to impact the trading
in Calpine's  securities," continued Kelly. "We look forward to providing a more
detailed  discussion  of  Calpine's  earnings  and  liquidity  in our May 5 news
release and conference call."

Cash and Earnings Update
- ------------------------

     Calpine  ended  the  quarter  with  cash  and cash  equivalents  on hand of
approximately  $800  million.  In addition,  the  company's  current  portion of
restricted cash totaled approximately $500 million.

     EBITDA,  as adjusted  for  non-cash  and other  charges,  is expected to be
approximately  $240 million for the quarter  ended March 31, 2005.  For the year
ended Dec. 31, 2005,  Calpine is confirming that the company expects EBITDA,  as
adjusted  for  non-cash  and  other  charges,  to be in the range of $1.6 - $1.7
billion.

     The recent market activity in the capital markets has not impacted  Calpine
Energy  Services' (CES) ability to manage its portfolio of assets.  In addition,
CES remains fully  collateralized with most of its  counterparties,  and has not
been  forced  to post any  material  margin  over the past  week  directly  with
counterparties.

     Although the company did not issue  quarterly  earnings  guidance,  pre-tax
earnings for the three  months ended March 31, 2005 were in-line with  Calpine's
internal  estimates.  Calpine is anticipating a fully-diluted  loss per share of
approximately  $0.38 for the first quarter.  The company  expects to achieve its
forecasted  earnings  for the year ending Dec.  31,  2005,  with a GAAP loss per
share  remaining in the range of $0.80 - $0.90 based on indications  that market
spark spreads are remaining in-line with our earlier expectations.

     Calpine  will host a  conference  call to discuss  its first  quarter  2005
financial and operating  results on Thursday,  May 5, 2005, at 8:30 a.m. Pacific
Daylight Time.  Interested  parties may access the teleconference via a web cast
on  Calpine's   Investor   Relations  page,   www.calpine.com,   or  by  dialing
1-888-603-6685  (1-706-634-1265 for international callers) at least five minutes
before  the  start  of the  call.  The  call  will be open  to the  public  in a
listen-only mode by telephone and web broadcast.  A replay and transcript of the
conference  call will be available for 30 days on Calpine's  Investor  Relations
page at www.calpine.com.

     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 the United Kingdom.  In
2004, Calpine delivered  approximately  3.5% of all electricity  consumed in the
United States. 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.

     For the company, EBITDA is not a measure of operating results, but rather a
measure of its ability to service debt and to raise additional  funds. It should
not be construed as an alternative to either (i) income from  operations or (ii)
cash flows from  operating  activities.  It is defined as net income less income
from  unconsolidated   investments,   plus  cash  received  from  unconsolidated
investments;   plus  provision  for  tax;  plus  interest   expense   (including
distributions  on trust  preferred  securities and one-third of operating  lease
expense,  which is  management's  estimate of the  component of operating  lease
expense that constitutes  interest expense);  plus  depreciation,  depletion and
amortization. The interest, tax, and depreciation and amortization components of
discontinued  operations are added back in calculating EBITDA, as adjusted.  The
non-GAAP  measure,  EBITDA,  as adjusted  for  non-cash  and other  charges,  is
presented  as a further  refinement  of EBITDA,  as  adjusted,  to  reflect  the
company's ability to service debt with cash.

     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 as, but not
limited to, (i) the timing and extent of  deregulation of energy markets and the
rules and regulations adopted on a transitional basis with respect thereto; (ii)
the timing and extent of changes in  commodity  prices for energy,  particularly
natural gas and electricity;  (iii) commercial operations of new plants that may
be delayed or prevented because of various  development and construction  risks,
such as a failure  to obtain  the  necessary  permits  to  operate,  failure  of
third-party  contractors to perform their contractual  obligations or failure to
obtain  financing on acceptable  terms;  (iv)  unscheduled  outages of operating
plants; (v) a competitor's  development of lower cost generating gas-fired power
plants; (vi) risks associated with marketing and selling power from power plants
in the newly-competitive  energy market; (vii) the successful exploitation of an
oil or gas resource  that  ultimately  depends upon the geology of the resource,
the total  amount  and costs to  develop  recoverable  reserves  and  operations
factors  relating to the  extraction  of natural gas;  (viii) the effects on the
company's  business  resulting  from reduced  liquidity in the trading and power
industry;  (ix) the  company's  ability to access the capital  markets or obtain
bank financing on attractive  terms;  (x) the direct or indirect  effects on the
company's business of a lowering of its credit rating (or actions it may take in
response to changing credit rating criteria),  including,  increased  collateral
requirements,  refusal by the company's  current or potential  counterparties to
enter into transactions with it and its inability to obtain credit or capital in
desired  amounts or on favorable  terms;  and (xi) other 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 Dec. 31, 2004,  which can also 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.