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EXHIBIT 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the incorporation by reference in the Registration Statement (Form
S-8 No. 333-00000) pertaining to the 1995 Stock Plan (as amended and restated
October 26, 2000) and the 2000 Employee Stock Purchase Plan of Catalytica Energy
Systems, Inc. (formerly Catalytica Combustion Systems, Inc.) of our report dated
August 25, 2000, with respect to the combined financial statements of Catalytica
Energy Systems, Inc. (formerly Catalytica Combustion Systems, Inc.) and
Catalytica Advanced Technologies, Inc. (a combined company in the development
stage) included in its Prospectus filed with the Securities and Exchange
Commission on November 21, 2000.
/s/ Ernst & Young LLP
San Jose, California
December 26, 2000
