UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K/A

CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): September 2, 2004

Calpine Corporation

(A Delaware Corporation)

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

      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 (see General Instruction A.2. below):

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

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

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

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

TABLE OF CONTENTS

	Section 1 -- Registrant’s Business and Operations
	Item 1.01. Entry into a Material Definitive Agreement
	Section 2 -- Financial Information
	Item 2.01. Completion of Acquisition or Disposition of Assets
	Item 2.05. Costs Associated with Exit or Disposal Activities
	Section 8 -- Other Events
	Item 8.01. Other Events
	Section 9 -- Financial Statements and Exhibits
	Item 9.01. Financial Statements and Exhibits
SIGNATURES
EXHIBIT INDEX
EXHIBIT 99.1
EXHIBIT 99.2
EXHIBIT 99.3
EXHIBIT 99.4
EXHIBIT 99.5

Explanatory Note

      On September 8, 2004, Calpine Corporation (“Calpine”) filed a Current Report on Form 8-K to report the sale of its Rocky Mountain and Canadian gas reserves. Calpine is filing this Current Report on Form 8-K/A to amend Item 9.01(b) as reported in such previous Current Report to provide further information regarding the tax implications associated with the Canadian gas reserves sale.

Section 1 — Registrant’s Business and Operations

Item 1.01.     Entry into a Material Definitive Agreement

      Calpine Corporation (the “Registrant”) entered into three material definitive agreements in the aggregate; to dispose of a significant portion of its oil and gas assets not made in the ordinary course of business of the Registrant. These agreements are outlined below:

Agreement no. 1:

      Calpine Natural Gas L.P. (“CNG”) and the Registrant (collectively the “Seller”), entered into an agreement with Pogo Producing Company (“Pogo”), the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of Seller’s right, title and interest in its oil and gas properties and associated assets in New Mexico, including all of Seller’s leases, minerals, overrides, easements, wells, contracts, and personal property (“New Mexico Properties”). The cash consideration was $83.1 million, which included a $3 million performance deposit. Although no purchase price adjustments were made prior to the closing on September 1, 2004, the Purchase and Sale Agreement with Pogo does provide for a post-closing settlement for: (1) certain title defects claimed by Pogo before Closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign certain New Mexico Properties, and (3) revenues and costs before and after the Effective Date.

      The New Mexico Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States. As noted above, the Seller retains responsibility for curing (or making a purchase price adjustment for) certain title defects claimed by Pogo. In addition, the Seller has agreed to indemnify Pogo for up to one-half of the purchase price for claims: (1) related to pre-Effective Date liabilities (other than certain environmental and title defects) and (2) made on or before December 31, 2005. Pogo agrees to indemnify the Seller for all post-Effective Date liabilities.

      This agreement has been attached under Item 9.01(c) as Exhibit 99.1.

Agreement no. 2:

      CNG and the Registrant (collectively with CNG the “Seller”), entered into an agreement with Bill Barrett Corporation, the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of the Seller’s right, title and interest in its oil and gas properties and associated assets in Colorado (except for CNG’s Kitzmiller property in the north-west part of the state which were retained by the seller), including leases, minerals, overrides, easements, wells, contracts, and personal property (“Colorado Properties”). The purchase price was $139.7 million, which included a $7.0 million performance deposit. Although no purchase price adjustments were made prior to the closing on September 1, 2004, the Purchase and Sale Agreement with Bill Barrett Corporation does provide for a post-closing settlement for: (1) certain environmental and title defects claimed by Bill Barrett Corporation before closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign for certain Colorado Properties and (3) revenues and costs before and after the Effective Date.

      The Colorado Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States. As noted above, the Seller retains responsibility for curing (or making a purchase price adjustment for) certain title defects claimed by Barrett. In addition, the Seller has agreed to indemnify Bill Barrett Corporation for up to one-half of the purchase price for claims: (1) related to pre-Effective Date liabilities (other than certain environmental and title defects) and (2) made on or before one year following the closing. Barrett agrees to indemnify Seller for all post-Effective Date liabilities.

      This agreement has been attached under Item 9.01(c) as Exhibit 99.2.

1

Agreement no. 3:

      Calpine Canada Natural Gas Partnership (“CCNGP”) and Calpine Energy Holdings Limited (“CEHL”), entered into an agreement with PrimeWest Gas Corp. and PrimeWest Energy Trust, the Buyer, to sell, effective July 1, 2004, all of CCNGP’s interest in oil and gas properties located in Canada and all of CEHL’s ownership interest in 6.8 million units of Calpine Natural Gas Trust (“CNGT”), for cash consideration of CND$825.0 million, or approximately US$625.0 million, less adjustments of CND$15.6 million, to reflect a September 2, 2004, closing date. The agreement contained standard terms and conditions relating to the sale of oil and gas properties in Alberta. The transaction closed on September 2, 2004.

      As a result of the sale of the trust units of CNGT, the Registrant’s obligations under various agreements with CNGT have been terminated. This included the Registrant’s obligations under the energy management agreement, the participation agreement (wherein the Registrant had agreed to offer 50% of any future acquisition of properties to the CNGT) and the call on production agreement (wherein the Registrant had the right to purchase all of the CNGT’s production at index pricing, secured by the trust units owned by the Registrant).

      This agreement has been attached under Item 9.01(c) as Exhibit 99.3.

Section 2 — Financial Information

Item 2.01.     Completion of Acquisition or Disposition of Assets

      Calpine Corporation (the “Registrant”) completed the disposition of a significant amount of its oil and gas assets outside the ordinary course of business. A description of the transactions that represent the disposition of a significant amount of assets is listed below.

      Calpine Natural Gas L.P. (“CNG”) and the Registrant, (collectively the “Seller”), entered into an agreement with Pogo Producing Company (“Pogo”), the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of Seller’s right, title and interest in its oil and gas properties and associated assets in New Mexico, including all of Seller’s leases, minerals, overrides, easements, wells, contracts, and personal property (“New Mexico Properties”). The cash consideration was $83.1 million, which included a $3 million performance deposit. Although no purchase price adjustments were made prior to the closing on September 1, 2004, the Purchase and Sale Agreement with Pogo does provide for a post-closing settlement for: (1) certain title defects claimed by Pogo before the closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign certain New Mexico Properties, and (3) revenues and costs before and after the Effective Date. The New Mexico Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States.

      CNG and the Registrant (collectively with CNG the “Seller”), entered into an agreement with Bill Barrett Corporation, the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of the Seller’s right, title and interest in its oil and gas properties and associated assets in Colorado (except for CNG’s Kitzmiller property in the north-west part of the state which were retained by the Seller), including leases, minerals, overrides, easements, wells, contracts, and Colorado Properties. The purchase price was $139.7 million, which included a $7.0 million performance deposit. Although no purchase price adjustments were made prior to the closing on September 1, 2004, the Purchase and Sale Agreement with Bill Barrett Corporation does provide for a post-closing settlement for: (1) certain environmental and title defects claimed by Bill Barrett Corporation before closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign for certain Colorado Properties and (3) revenues and costs before and after the Effective Date. The Colorado Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States.

      Calpine Canada Natural Gas Partnership (“CCNGP”) and Calpine Energy Holdings Limited (“CEHL”), entered into an agreement with PrimeWest Gas Corp. and PrimeWest Energy Trust, the Buyer, to sell, effective July 1, 2004, all of CCNGP’s interest in oil and gas properties located in Canada and all of CEHL’s ownership interest in 6.8 million units of Calpine Natural Gas Trust (“CNGT”), for cash

2

consideration of CND$825.0 million, or approximately US$625.0 million, less adjustments of CND $15.6 million, to reflect a September 2, 2004, closing date. The agreement contained standard terms and conditions relating to the sale of oil and gas properties in Alberta. The transaction closed on September 2, 2004.

Item 2.05.     Costs Associated with Exit or Disposal Activities

      On September 1, 2004, as further described in Items 1.01 and 2.01 of the Form 8-K, the Registrant along with CNG completed the sale of its Rocky Mountain gas reserves that are primarily concentrated in two geographic areas: the Colorado Piceance Basin and the New Mexico San Juan Basin. Together, these assets represent approximately 120 billion cubic feet equivalent (“Bcfe”) of proved gas reserves, producing approximately 16.3 million net cubic feet equivalent (“MMcfed”) per day of gas. On September 2, 2004, the Registrant completed the sale of its Canadian natural gas reserves and petroleum assets. These Canadian assets represent approximately 221 Bcfe of proved reserves, producing approximately 61 MMcfed. Included in this sale was the Registrant’s 25 percent interest in approximately 80 Bcfe of proved reserves (net of royalties) and 32 MMcfed of production owned by the Calpine Natural Gas Trust (“CNGT”). In connection with the Registrant’s sale of its Canadian and Rocky Mountain gas reserves, the Registrant will incur one-time future cash expenditures associated with the sale, consisting of employee severance and other related one-time termination benefits of approximately $4.9 million pre-tax, various other exit costs of approximately $0.6 million pre-tax and closing fees of approximately $4.6 million pre-tax, for total pre-tax exit activity costs of approximately $10.1 million ($6.1 million net of tax).

Section 8 — Other Events

Item 8.01.     Other Events

      On September 2, 2004, the Registrant issued a press release attached hereto as exhibit 99.4 announcing the sale of its Rocky Mountain gas reserves. Also, on September 2, 2004, the Registrant issued a press release attached hereto as exhibit 99.5 announcing the completion of the sale of its Canadian gas reserves.

Section 9 — Financial Statements and Exhibits

Item 9.01.     Financial Statements and Exhibits

      (a) Financial Statements of Businesses Acquired

      Not Applicable

      (b) Pro Forma Financial Information

      Calpine Natural Gas L.P. (“CNG”) and the Registrant, (collectively the “Seller”), entered into an agreement with Pogo Producing Company (“Pogo”), the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of Seller’s right, title and interest in its oil and gas properties and associated assets in New Mexico, including all of Seller’s leases, minerals, overrides, easements, wells, contracts, and personal property (“Properties”). The cash consideration was $83.1 million, which included a $3 million performance deposit. Although no purchase price adjustments were made for operations prior to the closing on September 1, 2004, the Purchase and Sale Agreement (“PSA”) does provide for a post-closing settlement for: (1) certain environment and title defects claimed by Pogo before Closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign for certain Properties, and (3) revenues and costs before and after the Effective Date. The Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States.

      CNG and the Registrant (collectively the “Seller”), entered into an agreement with Bill Barrett Corp. (“Barrett”), the buyer, effective July 1, 2004 (the “Effective Date”), to sell all of the Seller’s Effective Date right, title and interest in its oil and gas properties and associated assets in Colorado (except for CNG’s Kitzmiller property that was retained in the north-west part of the state), including leases, minerals, overrides, easements, wells, contracts, and Properties. The purchase price was $139.7 million, which included a $7.0 million performance deposit. Although no purchase price adjustments were made for operations prior to September 1, 2004, the closing date, the PSA does provide for a post-closing settlement for: (1) certain

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environment and title defects claimed by the Barrett before Closing, provided that such defects cannot be resolved to the satisfaction of both parties, (2) adjustments if Seller is unable to obtain consents to assign for certain Properties and (3) revenues and costs before and after the Effective Date. The Properties were sold subject to certain warranties and representations that are customary in transactions of this type in the United States.

      Calpine Canada Natural Gas Partnership (“CCNGP”) and Calpine Energy Holdings Limited (“CEHL”), entered into an agreement with PrimeWest Gas Corp. and PrimeWest Energy Trust, the Buyer, to sell, effective July 1, 2004, all of CCNGP’s interest in oil and gas properties located in Canada and all of CEHL’s ownership interest in 6.8 million units of Calpine Natural Gas Trust (“CNGT”), for cash consideration of CND$825.0 million, or approximately US$625.0 million, less adjustments of CND$15.6 million, to reflect a September 2, 2004, closing date. The agreement contained standard terms and conditions relating to the sale of oil and gas properties in Alberta. The transaction closed on September 2, 2004 Effective Date.

      In connection with the Registrant’s sale of its Canadian gas reserves, the Registrant will incur one-time future cash expenditures associated with the sale, consisting of employee severance and other related one-time termination benefits of approximately $4.9 million pre-tax, various other exit costs of approximately $0.6 million pre-tax and closing fees of approximately $4.6 million pre-tax, for total pre-tax exit activity costs of approximately $10.1 million ($6.1 million net of tax). These charges, which will be made in the third quarter of 2004, were not considered in the historical Pro-Forma Consolidated Condensed Statements of Operations presented below.

      Following the sale of oil and gas assets in Canada, $225 million has been repatriated to the United States from the net cash proceeds. This dividend triggers an additional U.S. tax provision of approximately $90 million in 2004, which will be recorded by Calpine in the third quarter of 2004. Additionally, as a result of the sale of the Canadian oil and gas assets, we expect that Calpine’s effective tax rate will be negatively impacted in 2004 and future periods due to the inability to realize certain tax benefits. These tax consequences were not considered in the Pro Forma Consolidated Condensed Statements of Operations presented below.

      The unaudited Pro-Forma Consolidated Condensed Statements of Operations are presented for the six months ended June 30, 2004 and the year ended December 31, 2003 and present the Registrant’s operations as if the transactions described above had occurred at January 1 of each of the periods presented. An unaudited Pro-Forma Consolidated Condensed Balance Sheet as of June 30, 2004, is also presented. The unaudited Pro-Forma Consolidated Condensed Balance Sheet presents the property sales described above, as if they had occurred at January 1, 2004.

      The unaudited Pro-Forma Consolidated Condensed Financial Statements should be read in conjunction with the Registrant’s Financial Statements and related Notes included in the Registrant’s Report on Form 10-Q for the quarter ended June 30, 2004 and the Report on Form 10-K for the year ended December 31, 2003 filed with the Securities and Exchange Commission.

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CALPINE CORPORATION AND SUBSIDIARIES

PRO-FORMA CONSOLIDATED CONDENSED BALANCE SHEET

June 30, 2004

					Canadian			Rocky Mountain			New Mexico
			Actual		Gas Assets(1)			Gas Assets(1)			Gas Assets(1)			Pro-Forma
			(In thousands, except share and per share amounts)
			(Unaudited)
ASSETS
Current assets:
	Cash and cash equivalents		$	844,031	$	—		$	—		$	—		$	844,031
	Accounts receivable, net			1,170,130		—			—			—			1,170,130
	Margin deposits and other prepaid expense			406,741		—			—			—			406,741
	Inventories			144,913		(1,838	)		—			—			143,075
	Restricted cash			317,833		—			—			—			317,833
	Current derivative assets			338,805		—			—			—			338,805
	Current assets held for sale			—		1,838			—			—			1,838
	Other current assets			72,117		—			—			—			72,117
		Total current assets		3,294,570		—			—			—			3,294,570
Restricted cash, net of current portion				191,695		—			—			—			191,695
Notes receivable, net of current portion				225,396		—			—			—			225,396
Project development costs				151,084		—			—			—			151,084
Investments in power projects and oil and gas properties				417,303		(24,558	)		—			—			392,745
Deferred financing costs				423,499		—			—			—			423,499
Prepaid lease, net of current portion				383,940		—			—			—			383,940
Property, plant and equipment, net				21,031,174		(456,668	)		(65,654	)		(47,286	)		20,461,566
Goodwill, net				45,160		—			—			—			45,160
Other intangible assets, net				89,411		—			—			—			89,411
Long-term derivative assets				561,328		—			—			—			561,328
Long-term assets held for sale				—		481,226			65,654			47,286			594,166
Other assets				627,202		—			—			—			627,202
		Total assets	$	27,441,762	$	—		$	—		$	—		$	27,441,762
LIABILITIES & STOCKHOLDERS’ EQUITY
Current liabilities:
	Accounts payable		$	1,160,600		—			—			—		$	1,160,600
	Accrued payroll and related expense			72,644		—			—			—			72,644
	Accrued interest payable			362,497		—			—			—			362,497
	Income taxes payable			5,680		—			—			—			5,680
	Notes payable and borrowings under lines of credit, current portion			239,289		—			—			—			239,289
	Preferred interests, current portion			8,758		—			—			—			8,758
	Capital lease obligation, current portion			8,466		—			—			—			8,466
	CCFC I financing, current portion			3,208		—			—			—			3,208
	Construction/project financing, current portion			57,256		—			—			—			57,256
	Senior notes and term loans, current portion			14,500		(2,000	)		—			—			12,500
	Current derivative liabilities			383,097		—			—			—			383,097
	Current liabilities held for sale			—		4,330			—			—			4,330
	Other current liabilities			271,589		(2,330	)		—			—			269,259
		Total current liabilities		2,587,584		—			—			—			2,587,584
Notes payable and borrowings under lines of credit, net of current portion				861,424		—			—			—			861,424
Notes payable to Calpine Capital Trusts				1,153,500		—			—			—			1,153,500
Preferred interests, net of current portion				142,064		—			—			—			142,064
Capital lease obligation, net of current portion				283,005		—			—			—			283,005
CCFC I financing, net of current portion				784,661		—			—			—			784,661
CalGen/ CCFC II financing				2,448,907		—			—			—			2,448,907
Construction/project financing, net of current portion				1,723,040		—			—			—			1,723,040
Convertible Senior Notes Due 2006				72,126		—			—			—			72,126
Convertible Senior Notes Due 2023				900,000		—			—			—			900,000
Senior notes and term loans, net of current portion				9,370,936		(218,529	)		(48,949	)		(29,022	)		9,074,436
Deferred income taxes, net				1,185,712		—			—			—			1,185,712
Deferred revenue				110,087		—			—			—			110,087
Long-term derivative liabilities				599,495		—			—			—			599,495
Long-term liabilities held for sale				—		234,014			49,091			29,193			312,298
Other liabilities				267,769		(15,485	)		(142	)		(171	)		251,971
		Total liabilities		22,490,310		—			—			—			22,490,310
Minority interests				350,561		—			—			—			350,561
Stockholders’ equity:
	Preferred stock, $.001 par value per share; authorized 10,000,000 shares; none issued and outstanding in 2004 and 2003			—		—			—			—			—
	Common stock, $.001 par value per share; authorized 1,000,000,000 shares at December 31, 2003, and 2,000,000,000 shares at June 30, 2004; issued and outstanding 439,326,249 shares in 2004 and 415,010,125 shares in 2003			439		—			—			—			439
	Additional paid-in capital			3,109,778		—			—			—			3,109,778
	Retained earnings			1,468,619		—			—			—			1,468,619
	Accumulated other comprehensive income			22,055		—			—			—			22,055
		Total stockholders’ equity		4,600,891		—			—			—			4,600,891
		Total liabilities and stockholders’ equity	$	27,441,762	$	—		$	—		$	—		$	27,441,762

(1)  Assumes sale by Calpine Corporation on June 30, 2004.

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CALPINE CORPORATION AND SUBSIDIARIES

PRO-FORMA CONSOLIDATED CONDENSED STATEMENT OF OPERATIONS(1)(2)

Six Months Ended June 30, 2004

									Canadian			Rocky Mountain			New Mexico
						Actual			Gas Assets			Gas Assets			Gas Assets			Pro-Forma
						(In thousands, except per share amounts)
						(Unaudited)
Revenue:
	Electric generation and marketing revenue
		Electricity and steam revenue				$	2,558,678		$	—		$	—		$	—		$	2,558,678
		Sales of purchased power for hedging and optimization					876,680			—			—			—			876,680
			Total electric generation and marketing revenue				3,435,358			—			—			—			3,435,358
	Oil and gas production and marketing revenue
		Oil and gas sales					50,651			(19,108	)		(374	)		(1,384	)		29,785
		Sales of purchased gas for hedging and optimization					834,708			—			—			—			834,708
			Total oil and gas production and marketing revenue				885,359			(19,108	)		(374	)		(1,384	)		864,493
	Mark-to-market activities, net						(10,086	)		—			—			—			(10,086	)
	Other revenue						46,741			—			—			—			46,741
				Total revenue			4,357,372			(19,108	)		(374	)		(1,384	)		4,336,506
Cost of revenue:
	Electric generation and marketing expense
		Plant operating expense					399,498			—			—			—			399,498
		Transmission purchase expense					31,078			—			—			—			31,078
		Royalty expense					12,833			—			—			—			12,833
		Purchased power expense for hedging and optimization					820,108			—			—			—			820,108
			Total electric generation and marketing expense				1,263,517			—			—			—			1,263,517
	Oil and gas operating and marketing expense
		Oil and gas operating expense					45,770			(13,687	)		(1,290	)		(2,647	)		28,146
		Purchased gas expense for hedging and optimization					814,409			—			—			—			814,409
			Total oil and gas operating and marketing expense				860,179			(13,687	)		(1,290	)		(2,647	)		842,555
	Fuel expense						1,630,490			39,188			9,486			6,756			1,685,920
	Depreciation, depletion and amortization expense						311,203			(34,495	)		(3,099	)		(1,847	)		271,762
	Operating lease expense						54,762			—			—			—			54,762
	Other cost of revenue						48,988			—			—			—			48,988
				Total cost of revenue			4,169,139			(8,994	)		5,097			2,262			4,167,504
					Gross profit		188,233			(10,114	)		(5,471	)		(3,646	)		169,002
Loss (income) from unconsolidated investments in power projects and oil and gas properties							(1,788	)		2,586			—			—			798
Equipment cancellation and impairment cost							2,367			—			—			—			2,367
Project development expense							11,748			—			—			—			11,748
Research and development expense							8,939			—			—			—			8,939
Sales, general and administrative expense							118,225			(5,612	)		—			—			112,613
	Income from operations						48,742			(7,088	)		(5,471	)		(3,646	)		32,537
Interest expense							534,452			(9,920	)		(1,694	)		(1,120	)		521,718
Interest (income)							(21,981	)		—			—			—			(21,981	)
Minority interest expense							13,159			—			—			—			13,159
(Income) from repurchase of various issuances of debt							(3,394	)		—			—			—			(3,394	)
Other (income)							(203,996	)		—			—			—			(203,996	)
	Loss before (benefit) for income taxes						(269,498	)		2,832			(3,777	)		(2,526	)		(272,969	)
(Benefit) for income taxes							(146,553	)		1,109			(1,440	)		(1,003	)		(147,887	)
	Loss from continuing operations(3)					$	(122,945	)	$	1,723		$	(2,337	)	$	(1,523	)	$	(125,082	)
Basic and diluted loss per common share:
	Weighted average shares of common stock outstanding						416,332												416,332
	Loss from continuing operations(3)					$	(0.30	)										$	(0.30	)

(1)	The Pro-Forma Consolidated Condensed Statement of Operations assumes that the gas asset sales described above were sold by Calpine Corporation on January 1, 2003.
(2)	Operating results for the gas assets described above are their actual operating results from January 1 to their respective dates of sale.
(3)	Represents loss before discontinued operations and cumulative effect of a change in accounting principle.

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CALPINE CORPORATION AND SUBSIDIARIES

PRO-FORMA CONSOLIDATED CONDENSED STATEMENT OF OPERATIONS(1)(2)

Year Ended December 31, 2003

									Canadian			Rocky Mountain			New Mexico			Other			Pro-
						Actual			Gas Assets			Gas Assets			Gas Assets			Reclassifications(3)			Forma
						(In thousands, except per share amounts)
						(Unaudited)
Revenue:
	Electric generation and marketing revenue
		Electricity and steam revenue				$	4,695,744		$	—		$	—		$	—		$	(15,347	)	$	4,680,397
		Sales of purchased power for hedging and optimization					2,714,187			—			—			—			—			2,714,187
			Total electric generation and marketing revenue				7,409,931			—			—			—			(15,347	)		7,394,584
	Oil and gas production and marketing revenue
		Oil and gas sales					107,662			(46,920	)		(275	)		(1,311	)		—			59,156
		Sales of purchased gas for hedging and optimization					1,320,902			—			—			—			—			1,320,902
			Total oil and gas production and marketing revenue				1,428,564			(46,920	)		(275	)		(1,311	)		—			1,380,058
	Mark-to-market activities, net						(26,439	)		—			—			—						(26,439	)
	Other revenue						107,483			—			—			—			15,347			122,830
				Total revenue			8,919,539			(46,920	)		(275	)		(1,311	)		—			8,871,033
Cost of revenue:
	Electric generation and marketing expense
		Plant operating expense					679,031			—			—			—			(4,221	)		674,810
		Transmission purchase expense					—			—			—			—			34,690			34,690
		Royalty expense					24,932			—			—			—			—			24,932
		Purchased power expense for hedging and optimization					2,690,069			—			—			—			—			2,690,069
			Total electric generation and marketing expense				3,394,032			—			—			—			30,469			3,424,501
	Oil and gas operating and marketing expense
		Oil and gas operating expense					106,244			(24,011	)		(2,569	)		(4,211	)		—			75,453
		Purchased gas expense for hedging and optimization					1,279,568			—			—			—			—			1,279,568
			Total oil and gas operating and marketing expense				1,385,812			(24,011	)		(2,569	)		(4,211	)		—			1,355,021
	Fuel expense						2,564,742			76,778			14,590			9,508			—			2,665,618
	Depreciation, depletion and amortization expense						583,912			(69,056	)		(4,817	)		(2,724	)		—			507,315
	Operating lease expense						112,070			—			—			—			—			112,070
	Other cost of revenue						42,270			—			—			—			—			42,270
				Total cost of revenue			8,082,838			(16,289	)		7,204			2,573			30,469			8,106,795
					Gross profit		836,701			(30,631	)		(7,479	)		(3,884	)		(30,469	)		764,238
(Income) from unconsolidated investments in power projects and oil and gas properties							(76,703	)		898			—			—			—			(75,805	)
Equipment cancellation and impairment cost							64,384			—			—			—			—			64,384
Long-term service agreement cancellation charge							16,355			—			—			—			—			16,355
Project development expense							21,804			—			—			—			—			21,804
Research and development expense							—			—			—			—			10,630			10,630
Sales, general and administrative expense							265,653			(8,083	)		—			—			(41,099	)		216,471
Merger expense							—			—			—			—			—			—
	Income from operations						545,208			(23,446	)		(7,479	)		(3,884	)		—			510,399
Interest expense							726,103			(15,892	)		(2,271	)		(1,634	)		—			706,306
Distributions on trust preferred securities							46,610			—			—			—			—			46,610
Interest (income)							(39,716	)		—			—			—			—			(39,716	)
Minority interest expense							27,330			—			—			—			—			27,330
(Income) from repurchase of various issuances of debt							(278,612	)		—			—			—			—			(278,612	)
Other (income)							(46,126	)		—			—			—			—			(46,126	)
	Income before provision (benefit) for income taxes						109,619			(7,554	)		(5,208	)		(2,250	)		—			94,607
(Benefit) for income taxes							(134	)		(2,960	)		(1,980	)		(899	)		—			(5,973	)
	Income from continuing operations(4)					$	109,753		$	(4,594	)	$	(3,228	)	$	(1,351	)	$	—		$	100,580
Basic earnings per common share:
	Weighted average shares of common stock outstanding						390,772															390,772
	Income from continuing operations(4)					$	0.28														$	0.26
Diluted earnings per common share:
	Weighted average shares of common stock outstanding before dilutive effect of certain convertible securities						396,219															396,219
	Income from continuing operations(4)					$	0.28														$	0.25

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(1)	The Pro-Forma Consolidated Statement of Operations assumes that the gas asset sales described above were sold on January 1, 2003.
(2)	Operating results for the gas assets described above are their actual operating results from January 1 to their respective dates of sales.
(3)	Certain amounts in the Pro-Forma Consolidated Statement of Operations have been reclassified to conform to the 2004 presentation. Note that these reclassifications did not occur as a result of the disposition of the gas assets described above. These reclassifications include: (1) $15,347 from Electricity and Steam revenue to Other revenue representing Transmission revenue; (2) $34,690 from Plant operating expense to Transmission purchase expense; (3) $25,075 from Sales, general and administrative expense to Plant operating expense for information systems costs for the Company’s power plants; (4) $10,630 from Sales, general and administrative expense to Research and development expense; and (5) $5,394 from Sales, general and administrative expense to Plant operating expense for the Company’s stock option compensation expense.
(4)	Represents income before discontinued operations and cumulative effect of a change in accounting principle.

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      (c) Exhibits

99.1	—	Purchase and Sale Agreement among Calpine Corporation, Calpine Natural Gas L.P. and Pogo Producing Company dated July 1, 2004.
99.2	—	Purchase and Sale Agreement among Calpine Corporation, Calpine Natural Gas L.P. and Bill Barrett Corporation dated July 1, 2004
99.3	—	Asset and Trust Unit Purchase and Sale Agreement among Calpine Canada Natural Gas Partnership and Calpine Energy Holdings Limited and Calpine Corporation and PrimeWest Gas Corp. and PrimeWest Energy Trust dated July 1, 2004.
99.4	—	Press release dated September 2, 2004, indicating the Registrant’s sale of its Rocky Mountain gas reserves.
99.5	—	Press release dated September 2, 2004, indicating the Registrant’s sale of its Canadian gas reserves.

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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 and Corporate Controller, Chief Accounting Officer

Date: September 14, 2004

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EXHIBIT INDEX

Exhibit
No.			Description
	99	.1	Purchase and Sale Agreement among Calpine Corporation, Calpine Natural Gas L.P. and Pogo Producing Company dated July 1, 2004.
	99	.2	Purchase and Sale Agreement among Calpine Corporation, Calpine Natural Gas L.P. and Bill Barrett Corporation dated July 1, 2004.
	99	.3	Asset and Trust Unit Purchase and Sale Agreement among Calpine Canada Natural Gas Partnership and Calpine Energy Holdings Limited and Calpine Corporation and PrimeWest Gas Corp. and PrimeWest Energy Trust dated July 1, 2004.
	99	.4	Press release dated September 2, 2004, indicating the Registrant’s sale of its Rocky Mountain gas reserves.
	99	.5	Press release dated September 2, 2004, indicating the Registrant’s sale of its Canadian gas reserves.