Fervo Energy Signs World’s Largest Geothermal Power Purchase Agreements with Southern California Edison

Houston-based Fervo Energy, a pioneer in the development of enhanced geothermal systems (EGS) using hydraulic fracturing to produce geothermal energy, has signed two power purchase agreements (PPAs) with Southern California Edison (SCE) to deliver 320 MW of electricity.

The 15-year agreements represent the world’s largest geothermal PPA to date, Fervo said in a June 25 press release.

SCE will purchase power from the 400-MW Fervo Energy Cape Station project currently under construction in Beaver County, Utah. The first phase of the 70-MW project is expected to be online by 2026 and operational by 2028.

Through the agreement with SCE, Fervo has contracted 373 MW of the Cape Stations’ target capacity of 400 MW.

The Cape Station project involves drilling up to 29 wells, of which 21 will be horizontal EGS wells using hydraulic fracturing to increase the flow of hot water and eight vertical observation wells.

The target depth of the horizontal geothermal injection and production wells is expected to be approximately 8,000 feet, with branches extending to a depth of approximately 5,000 feet.

Fervo recently selected Mitsubishi subsidiary Turboden to design and deliver the first phase of three generators for Cape Station. The generators will be equipped with six Turboden closed-cycle turbines.

Adding Critical Base Load

Commenting on Fervo’s PPA announcement, California Energy Commission Chairman David Hochschild said geothermal energy “is critical to ensuring (grid) reliability” because it can provide “critical baseload” when wind and solar resources are limited.

The California Public Utilities Commission issued a Medium Term Reliability (MTR) Order in 2021 requiring utilities to purchase 1,000 MW of weather-neutral, non-battery-based, zero-emission power to improve the reliability of the state’s electricity grid.

The decision boosted demand for geothermal energy despite its higher costs — a fact that had favored wind and solar power until weather and battery issues were taken into account.

The Golden State is the largest producer of geothermal energy in the U.S., based on the strength of its volcanic activity, although, paradoxically, geothermal energy makes up just 22% of California’s renewable energy mix, according to California Audubon.

California is home to the world’s largest geothermal field: Geysers, located 72 miles north of San Francisco, has the capacity to generate 1,800 MW of electricity, according to the U.S. Department of the Interior’s Bureau of Land Management (BLM).

The Geysers field lies at the southwestern end of the Clear Lake volcanic field, according to the U.S. Geological Survey, which also includes the Salton Sea resource in the Imperial Valley (which the BLM estimates could provide 2,200 MW) and the Mammoth Geothermal Complex in the Long Valley Caldera, all of which currently provide geothermal energy to the grid.

Reducing the Cost of Geothermal Energy

Fervo is betting its approach, which leverages core oil and gas technologies including fracking, will drive down costs and make zero-carbon geothermal energy an increasingly larger share of the renewable energy mix.

At a February 2024 Geothermal Engineers Workshop at Stanford University, Fervo presented results from its drilling technology, which demonstrated shorter drilling times and overall cost reductions at Cape Station.