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 Quarterly  Report of Calpine  Corporation (the "Company")
on Form 10-Q for the period ending June 30, 2002,  as filed with the  Securities
and Exchange Commission on the date hereof (the "Report"),  I, Peter Cartwright,
Chairman,  President  and Chief  Executive  Officer  of the  Company,  do hereby
certify,  pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906
of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge, based upon
a review of the Report:

     (1) The 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  Report  fairly  presents,  in all
material  respects,  the  financial  condition  and results of  operation of the
Company.



/s/  PETER CARTWRIGHT

Peter Cartwright
Chairman, President and Chief
Executive Officer
Calpine Corporation
August 9, 2002