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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 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
August 25, 2000
