- Project Owner
- Calpine Geysers Power Company, LLC
- Docket Number
- 79-AFC-03C
- Capacity
- 110 MW
- Location
- Sonoma County
- Technology
- Steam Turbine
- Project Status
- Operational (Geothermal)
- Project Type
- Application for Certification
The Socrates Geothermal project (Unit 18) is in Sonoma County near the Sonoma/Lake County line, in the Geysers Known Geothermal Resource Area along the ridgeline of the Mayacamas Mountains with moderately steep terrain, approximately 15 miles west of the town of Cobb. Unit 18, originally known as Pacific Gas & Electric Company’s (PG&E) Geysers Unit 18 Geothermal Project was certified by the California Energy Commission (CEC) in May 1980 and began commercial operation in November 1982.
Unit 18 is a dry-steam geothermal plant and was designed to provide up to 110 MW; however, due to reduced steam pressures, the plant currently supplies approximately 50 megawatts of base-load electricity to northern California's power grid. The major structures of the proposed facility are a turbine building, cooling tower, electrical switchyard, and a hydrogen sulfide abatement facility. The turbine building would house the steam turbine generator and other associated equipment required for electrical power production. The mechanical draft cooling tower would dissipate to abate hydrogen sulfide (H2S) emissions using a Stretford System which scrubs heat from the H2S from the vent gas stream from the condenser and catalytically oxidizes the gas to eliminate Sulfur.
In April 1999, the CEC granted a transfer of ownership of Socrates Geothermal (Unit 18), the former PG&E Geysers Unit 18 Geothermal Project to Geysers Power Company, LLC, a wholly owned subsidiary of the Calpine Corporation.
- Settlement for Fire Protection System
Commission Approval
Order No. 20-1116-02
TN 235700
11/19/20 - Resolution for (DCBO) services for Fire System Recommissioning Activities
Commission Approval
Resolution No. 19-1014-04
TN 230279
10/18/2019 - Replacement of Temporary Portable Emergency Diesel Engines
Commission Approval
Order No. 18-1210-02
TN 226128
12/12/2018 - Expedited Processing Pursuant to Executive Order B-36-15
Executive Director Approval
TN 207191
01/05/2016 - Expedited Processing Pursuant to Executive Order B-36-15
Commission approval
Order B-36-15
TN 206740
11/23/2015 - Authorization for Calpine to Obtain Demolition Permits from Sonoma and Lake Counties for Demolition
Staff Approval
TN 206306
11/19/2015 - Modifications to Verifications for Air Quality Conditions of Certification
Staff Approval
Not in Docket
03/23/1995 - Use of Reclaimed Wastewater and Approval of Verification Changes
Staff Approval
TN 31109
03/12/2004 - Ownership Transfer to Geysers Power Company
Commission Approval
Order No. 99-0414-01b TN 11773
04/22/1999 - Modification of Verifications for Air Quality Conditions of Certification
Staff Approval
Not in Docket
03/23/1995 - Modification of Compliance Plan to Add Approved Change to Air Quality Condition of Certification AQ-55
Commission Approval
Order No. 83-0325
Not in Docket
03/25/1983
Attention: You will need to look up the transaction number (TN) in the Compliance Docket Log. Non-hypertext items in the docket indicate that no electronic or hard copy is available or the item was filed confidentially. If you have any questions, please contact the Compliance Project Manager assigned to this project.
Power Plant Certification and Exemption Processes
The CEC has the exclusive authority to certify all thermal power plants 50 megawatts (MW) and larger and related facilities proposed for construction in California. The Application for Certification (AFC) process is a certified regulatory program under the California Environmental Quality Act (CEQA). As a certified regulatory program, the CEC does not prepare environmental impact reports (EIRs) in an AFC proceeding, but instead prepares environmental assessment documents that are functionally equivalent to EIRs. A certificate issued by the CEC is in lieu of any permit, certificate, or similar document otherwise required by any state, local or regional agency, or federal agency to the extent permitted by federal law, and supersedes any applicable statute, ordinance, or regulation of any state, local, or regional agency, or federal agency to the extent permitted by federal law.
Original Proceeding
e-Commenting has been closed. Please submit your comments in compliance proceeding above.
Contacts
Project Manager
Rena Eddy
CME@energy.ca.gov
(Please enter project name in the email subject line)
916-796-5815
Public Participation Questions
Public Advisor
publicadvisor@energy.ca.gov
916-269-9595
Media Inquiries
Media & Public Communications Office
mediaoffice@energy.ca.gov
916-654-4989