Exhibit 8.1


                                                                 April 4, 2002


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

Calpine Capital Trust IV
c/o Calpine Corporation
50 West San Fernando Street
San Jose, CA 95113

Calpine Capital Trust V
c/o Calpine Corporation
50 West San Fernando Street
San Jose, CA 95113


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, pursuant to the
Shelf Registration Statement on Form S-3 (File No. 333-76880) initially filed
with the Securities and Exchange Commission on January 17, 2002 and amended on
April 4, 2002 (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, preferred stock, par value $.001 per share,
unsecured debt securities, depositary shares, purchase contracts, units and
warrants of Calpine Corporation (the "Company"), (ii) unsecured debt securities
of Calpine Canada Energy Finance ULC fully and unconditionally guaranteed by the
Company and warrants of Calpine Canada Energy Finance ULC, (iii) unsecured debt
securities of Calpine Canada Energy Finance II ULC fully and unconditionally
guaranteed by the Company and warrants of Calpine Canada Energy Finance II ULC,
(iv) the associated guarantees issued by the Company with respect to the debt
securities referred to in items (ii) and (iii) above, (v) preferred securities
of Calpine Capital

Trust IV, (vi) preferred securities of Calpine Capital Trust V, and (vii) the
associated guarantees issued by the Company with respect to the preferred
securities referred to in items (v) and (vi) above.

            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," insofar as such statements constitute summaries of the laws,
regulations or legal matters referred to therein, are, subject to the
qualifications stated therein, accurate in all material respects and fairly
summarize the matters referred to therein.

            The foregoing opinion is based on the Internal Revenue Code of 1986,
as amended, Treasury Regulations promulgated thereunder, Internal Revenue
Service 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


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