Exhibit 99.1

                            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 Company (the "Companies") on
Form 10-Q for the period ending September 30, 2002 as filed with the Securities
and Exchange Commission on the date hereof (the "Report"), I, Walter M. Higgins,
III, Chief Executive Officer of the Companies, certify, pursuant to 18 U.S.C.
ss. 1350, as adopted pursuant to ss. 906 of the Sarbanes-Oxley Act of 2002,
that:

         (1)      the combined Report fully complies with the requirements of
section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

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




/s/ Walter M. Higgins, III
- --------------------------------------
Walter M. Higgins, III
Chief Executive Officer
November 14, 2002






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.