Fervo Energy and Google ink largest-ever geothermal PPA to power data centers

Geothermal developer Fervo Energy has announced a record-breaking 396-megawatt (MW) power purchase agreement (PPA) with Google to enable the continued development of the Cape Station enhanced geothermal systems (EGS) GeoCluster, expected to come online in 2028. Under the agreement, Google will purchase carbon-free energy designed to serve as a “foundational building block” for a potential data center in Utah. As part of the PPA, Fervo will offer Google an option to expand its offtake by approximately 600 MW, for a total of nearly 1 gigawatt (GW) by June 2030. Final data center plans remain subject to a variety of factors including engineering feasibility, state and local approvals, and commercial conditions, the companies said. Fervo stressed that this deal unlocks new, around-the-clock electricity capacity at no cost to existing ratepayers. “This agreement reinforces that EGS is ready to power the next generation of computing infrastructure,” said Tim Latimer, CEO and co-founder of Fervo Energy. “As demand for reliable electricity grows, customers like Google need energy resources that can be deployed at scale, operate around the clock, and deliver where power is needed. This new PPA is part of our repeatable commercial model that enables us to meet customer needs and directly deliver clean, firm power to large electricity users. We’re proud to do this work in close partnership with the communities of Southwest Utah and with a partner that upholds our community-first values.” The Fervo-Google partnership began with Project Red, Fervo’s commercial pilot project in Nevada that came online in 2023. That pilot delivers power to the local grid, including Google’s data centers in the state. Following Project Red, Fervo signed a 115 MW PPA with Google and NV Energy in June 2024 that helped pioneer the Clean Transition Tariff, which Google argues enabled it to bring more geothermal energy onto the Nevada grid while insulating customers from the project’s costs. “The next chapter of advanced power generation technology is being written in Utah,” said Michael Terrell, head of advanced energy at Google. “This project will drive meaningful economic benefit to the local community and help catalyze long-term energy cost reductions by making enhanced geothermal more affordable and accessible.” Cape Station This PPA is part of the ongoing expansion of Cape Station beyond its initial 100 MW phase, as Fervo further scales its operations. Cape Station is the world’s largest enhanced geothermal systems (EGS) development and is expected to begin delivering electricity to the grid this year. The project includes Cape Station Phase I, which is poised to deliver 100 MW of clean baseload power to the grid beginning in 2026, as well as Cape Station Phase II, which will generate an additional 400 MW and come online by 2028. The full Cape Station development has received permitting approval for up to 2 GW of reliable and renewable energy. The project is an enhanced geothermal system that produces energy by injecting water into hot subsurface rock formations and then extracting the heated water to generate electricity, rather than depending on naturally occurring underground hot water like traditional geothermal systems. If fully developed, the project will cover approximately 631 acres, including 148 acres on public lands. Utah is home to immense geothermal potential. Researchers estimate that the southwest portion of the state contains more than 10 GW of high-quality geothermal reserves. Additionally, Cape Station will benefit from the Department of Energy’s Frontier Observatory for Research in Geothermal Energy (FORGE). Over the last several years, FORGE has completed research that has advanced geothermal development in the region. The United States boasts roughly 4,000 MW of installed geothermal, about one-quarter of the world’s total capacity. Most of it is in California (66.6% of 2023 total U.S. geothermal generation) and Nevada (26.1%), with smaller concentrations of development in Utah (3.2%), Hawai’i (2.1%), Oregon (1.3%), Idaho (.5%), and New Mexico (.2%). should we be using more geothermal? Last year, the U.S. Department of Energy (DOE) Advanced Research Projects Agency-Energy (ARPA-E) announced $30 million to increase geothermal power production by unlocking “superhot” reservoirs deep within the Earth. ARPA-E’s Stimulate Utilization of Plentiful Energy in Rocks through High-temperature Original Technologies (SUPERHOT) program aims to provide access to superhot reservoirs capable of producing 10-20 GW of reliable baseload power at a “competitive cost” of less than $30 per megawatt hour (MWh) by 2040. As the demand for power increases in the U.S., driven primarily by data centers and manufacturing, DOE argues that expanding geothermal power production could play an important role. EGS and AGS technology create engineered geothermal systems wherever hot rock exists either by creating subsurface fracture networks or drilling long boreholes. However, the highest temperatures that can be accessed are about 220 °C due to the lack of commercial, off-the-shelf equipment capable of handling higher temperatures, DOE said. This relatively low temperature limits the power production for EGS to about 10 megawatts-electric (MWe) per well site. DOE maintains that the ability to access superhot reservoirs will increase the electrical power per well, potentially up to 30-50 MWe, as both available subsurface heat and thermal-to-power efficiency increase. High temperature subsurface rocks exist everywhere but vary greatly in depth. In volcanic regions with a high geothermal gradient (e.g., parts of Hawaii, Alaska, and the West Coast) temperatures of 375 °C may be found at depths as shallow as 5 km. Elsewhere, it will be necessary to drill to depths of 10 km (or more). Drilling wells greater than 9 km has been possible for decades in areas with lower geothermal gradients, although none reached superhot temperatures. Previous attempts have been made to produce geothermal power from superhot reservoirs. Roughly 20 vertical and near-vertical boreholes have been drilled to temperatures as hot as 500 °C and to depths up to 5 km, DOE said, but most wells failed rapidly, and none are currently producing power. Several key factors make construction of superhot wells difficult: high-performance metal alloys and materials are expensive for the quantities needed for kilometers of geothermal casing; installation and deployment require well-vetted procedures; and superhot geothermal technology experiences extreme conditions including high temperatures, high-pressure corrosive fluids, and repeated thermal cycling.