Geothermal energy is a renewable energy source that has been providing California with clean, reliable, and affordable electricity for over 50 years. California contains the largest amount of geothermal generating capacity in the nation, with 25 known geothermal resource areas in the state. The major geothermal production areas in the state are in the Counties of Sonoma, Lake, Imperial, Inyo, and Mono.
The Commission's Geothermal Program began over 50 years ago with the issuance of the state's first geothermal prospecting permit near the Salton Sea in Imperial County. Actual production and use of geothermal resources from state owned lands managed by the Commission has been occurring for nearly four decades at the Geysers Field, which is the world's most developed geothermal resource area.
The Commission's Geothermal Program seeks to develop geothermal resources on state owned lands in an innovative, safe, and environmentally protective manner. To advance this goal, the Commission maximizes royalty revenue to the state and assures environmental protection and public safety. The Commission also endeavors to harness the geothermal potential on state owned lands to facilitate the state’s ambitious renewable energy goals, which require 50 percent of our energy to come from renewable sources by 2030.
Commission staff employs skill and expertise in several specialized areas to manage geothermal development on state owned lands. Drilling proposals require a technical review by engineering personnel. Drilling and production operations are witnessed by field inspection staff for compliance with safety and pollution prevention regulations. Production reports, royalty calculations, and payments are verified by staff with expertise in geothermal operations and lease terms.
Geothermal leases involving state owned lands are issued to companies that drill wells to extract geothermal fluids - either dry steam or hypersaline brine that flashes to steam. The companies use the steam, together with steam from adjacent federal and private leaseholds, to generate electrical power. At present, there are active geothermal operations on 7,247 acres of state school lands at the Geysers, and on 615 acres owned by the California Department of Fish and Wildlife at the Salton Sea geothermal field in Imperial County. The Commission has authority to issue geothermal leases on lands owned by another state agency subject to that agency's consent. The electricity generated from geothermal resources on state-owned lands currently powers approximately 240,000 average homes.