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Exhibit 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" and
"Selected Financial Data" and to the use of our report dated August 25, 2000
in Amendment No. 1, to the Registration Statement (Form S-1 No. 333-00000) and
related Prospectus for Catalytica Combustion Systems, Inc. and Catalytica
Advanced Technologies, Inc. (a combined company in the development stage) for
the registration of its common stock.
/s/ Ernst & Young LLP
San Jose, California
September 5, 2000
