EXHIBIT 32.2

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the combined quarterly report of Sierra Pacific Resources,
Nevada Power Company and Sierra Pacific Power Company (the "Companies") on Form
10-Q for the fiscal quarter ended September 30, 2004 as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), I, Michael
W. Yackira, Chief Financial Officer of the Companies, certify, pursuant to 18
U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
Act of 2002, that:

      1.    the combined quarterly report fully complies with the requirements
            of section 13(a) or 15(d) of the Securities Exchange Act of 1934, as
            amended; and

      2.    the information contained in the combined quarterly report fairly
            presents, in all material respects, the financial condition and
            results of operations of the Companies.

/s/ Michael W. Yackira
------------------------
Michael W. Yackira
Chief Financial Officer

November 9, 2004

This Certification accompanies this Report pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the
Sarbanes-Oxley Act of 2002, be deemed filed by the Company for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise
subject to the liability of that section. Such certification will not be deemed
to be incorporated by reference into any filing under the Securities Act or the
Exchange Act, except to the extent the Companies specifically incorporate it by
reference.

A signed original of this written statement required by Section 906 has been
provided to the Companies and will be retained by the Companies and furnished to
the Securities and Exchange Commission or its staff upon request.

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