EGS at The Geysers

The northwest Geysers area has been difficult to develop and produce due to high concentrations of noncondensible and corrosive gases. Deep temperatures in this part of the field are, however, the hottest seen at The Geysers to date. If EGS methods can be successfully employed in this part of the field, The Geysers could produce even more power than it does today. As part of a DOE-sponsored EGS field demonstration project, Calpine recently reopened and deepened two wells that were drilled in the 1980s and capped and abandoned in 1999.

By injecting water, Calpine expects to increase permeability in the rock, increase steam production, and reduce the concentrations of naturally occurring noncondensible gases (NCGs) such as carbon dioxide (CO2), hydrogen (H2) and hydrogen sulfide (H2S). The results of this EGS project to date are very encouraging. The outcome of this project will be important not only at The Geysers but at other geothermal sites around the world that

Calpine and U.S. DOE EGS Project at The Geysers - Community Updates

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To learn more about EGS, visit the Geothermal Technologies Office website at, email or click the links above to review public meeting presentations.