Exhibit 23.4

Gilbert Laustsen Jung
Associates Ltd. Petroleum Consultants
4100, 400 — 3rd Avenue S.W., Calgary, Alberta, Canada T2P 4H2 (403) 266-9500 Fax (403) 262-1855

LETTER OF CONSENT

     We hereby consent to the incorporation by reference in this Post-Effective Amendment No. 1 on Form S-3 pertaining to the 4.75% Contingent Convertible Senior Notes Due November 15, 2023 of Calpine Corporation included in Calpine Corporation’s Annual Report on Form 10-K for the year ended December 31, 2004 regarding Calpine Corporation’s estimated Canadian proved reserves and to the references to this firm included in such Report.

Yours truly,

GILBERT LAUSTSEN JUNG
ASSOCIATES LTD.

ORIGINALLY SIGNED BY

Myron J. Hladyshevsky, P. Eng.
Vice-President

Calgary, Alberta
April 19, 2005