- Docket Number
- 110 MW
- Sonoma County
- Steam Turbine
- Project Status
- Operational (Geothermal)
- Project Type
- Application for Certification
Northern California Power Agency (NCPA) Geothermal Plant No. 2 (NCPA-2) is located in located on a federal land approximately 60 miles northwest of Sacramento on the Sonoma County side of the Mayacmas Mountain ridgeline above the Big Sulphur Creek and Bear Canyon Creek drainages, just west of the Sonoma/Lake County line. The project is located in an unincorporated area of Sonoma County near the town of Anderson Springs where the geothermal steam wells are located.
NCPA-2 is a 110-megawatt generating geothermal facility consisting of steam wells, steam gathering system and reinjection wells of the steam supplier, a power plant and transmission tapline. NCPA-2 includes two 55 MW steam turbine-generator units, each capable of operating separately, if necessary, during scheduled or unscheduled shutdowns. Each turbine-generator has its own condensing system, cooling tower and electrical sub-station to step-up the voltage for transmission. The primary H2S abatement system uses a surface condenser to partition the spent steam, into condensate and non-condensable gases and solids that are treated by the Stretford System, which then scrubs heat from the H2S from the vent gas stream from the condenser and catalytically oxidizes the gas to eliminate Sulfur.
On June 1, 2020, the California Energy Commission staff approved the modernization of fire protection system for the purpose of replacing the degraded existing system and defective control panels. The recommissioning of the upgraded fire protection system is currently underway.
- Order Approving Amendment of Air Quality Determination of Compliance Condition No. 1, Not in Docket, 01/18/1989, Order No. 89-0118-01a, Commission approval to allow operation under conditions of July 26, 1988 Northern Sonoma County Air Pollution Control District (NSCAPCD) Protocol Agreement.
- Order Approving Termination of MOU Between the Energy Commission and the United States Geological Survey and Amendment of the Final Decision, TN 56611, 05/11/2010, Order No. 10-0505-f, Commission approval to terminate MOU with USGS effective February 1, 2010.
- Notice of Determination for Approval to Replace an Existing Hydrogen Peroxide Tank, TN 206721, 11/20/2015, Staff approval to replace existing 6,000-gallon hydrogen peroxide tank with similarly sized carbon steel tanks.
Attention: Non-hypertext items above will need to be requested from the Compliance Project Manager, along with the document TN number, if provided above.
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.