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                                                                     Exhibit 8.1


                                                             September 19,  2001


Calpine Corporation
50 West San Fernando Street
San Jose, CA 95113

Calpine Canada Energy Finance ULC
Suite 800, Purdy's Wharf, Tower 1
1959 Upper Water Street
P.O. Box 997
Halifax, Nova Scotia B3J 3N2

Calpine Canada Energy Finance II ULC
Suite 800, Purdy's Wharf, Tower 1
1959 Upper Water Street
P.O. Box 997
Halifax, Nova Scotia B3J 3N2


Ladies and Gentlemen:

               We have acted as your United States tax counsel in connection
with the registration under the Securities Act of 1933, as amended (the
"Securities Act"), pursuant to the Shelf Registration Statement on Form S-3
(File No. 333-67446) initially filed with the Securities and Exchange
Commission, on August 14, 2001 and amended on September 19, 2001 (such
Registration Statement, as amended or supplemented from time to time, is herein
referred to as the "Registration Statement"), of (i) common stock, par value
$.001 per share (the "Common Securities"), preferred stock, par value $.001 per
share (the "Preferred Securities"), and unsecured debt securities (the "Debt
Securities") of Calpine Corporation (the "Company"), (ii) unsecured debt
securities of Calpine Canada Energy Finance ULC fully and unconditionally
guaranteed by the Company (the "Energy Finance Debt Securities"), (iii)
unsecured debt securities of Calpine Canada Energy Finance II ULC fully and
unconditionally guaranteed by the Company (the "Energy Finance II Debt
Securities") and (iv) the associated guarantees issued by the Company with
respect to the Energy Finance Debt Securities and the Energy Finance II Debt
Securities (collectively, the "Guarantees").

               We have reviewed such corporate records, certificates and other
documents, and such questions of law, as we have considered necessary or
appropriate for the purposes of this opinion. We have assumed that all
signatures are genuine, that all documents submitted to us as originals are
authentic and that all copies of documents submitted to us conform to the
originals.

               Based upon and subject to the foregoing, the statements in the
Registration Statement under the caption "Certain United States Federal Income
Tax Consequences" represent our opinion of the United States federal income tax
law matters referred to therein and

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such statements are (subject to the qualifications and other matters stated
therein) accurate in all material respects.

               The foregoing opinion is based on the Internal Revenue Code of
1986, as amended, Treasury Regulations promulgated thereunder, Internal Revenue
Services rulings and pronouncements, and judicial decisions now in effect, any
of which may be changed at any time with retroactive effect.

               We are members of the bar of the State of New York. We do not
express any opinion on any matters other than the United States federal income
tax law matters specifically referred to herein.

               We hereby consent to the filing of this opinion as Exhibit 8.1 to
the Registration Statement. In giving such consent, we do not thereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Securities Act.

                                            Very truly yours,


                                            /s/ Covington & Burling