“Fervo Energy, a geothermal energy startup, has drilled what it calls its ‘hottest and deepest well to-date‘ in southwest Utah. The company also claims that its enhanced geothermal system can extract up to 60 percent of available underground heat, around three times more than conventional geothermal wells.”
Fervo Energy today [6/10/25] announced the successful drilling and logging of its Sugarloaf appraisal well, an operational achievement that demonstrates the rapid advancement and scalability of enhanced geothermal systems (‘EGS’). The well was drilled to a true vertical depth of 15,765 feet and is projected to reach a bottomhole temperature of 520 °F after full thermal equilibration. Fervo completed the Sugarloaf well in just 16 drilling days, representing a 79% reduction in drilling time compared to the US Department of Energy baseline for ultradeep geothermal wells.
While drilling what is Fervo’s hottest and deepest well to-date, the company was able to achieve multiple drilling performance records, including a maximum bit run length of 3,290 feet, a maximum average rate of penetration (‘ROP’) of 95 feet/hour, and an instantaneous ROP of over 300 feet/hour at depths greater than 15,000 feet. These results expand the window for commercial viability of EGS into a significantly deeper and hotter regime, paving the way to deploy the technology outside of the western US….
Fervo’s proprietary EGS design successfully unlocks thermal recovery factors in the range of 50 to 60%, tripling the amount of useful thermal energy reserves compared to conventional geothermal technology. The report confirms that the Cape Station project area can support over 5 GW of development at depths of up to 13,000 feet.
Geothermal energy may expand significantly due to fracking techniques, just as oil and gas production in the U.S. rose to record levels after fracking techniques were perfected.
“New experiments in the deserts of Utah and Nevada show how advances in fracking—technology developed by the oil industry—can be repurposed to tap clean geothermal energy anywhere on Earth,” reported Wired in 2023. So it will become possible to drill deep into the Earth to get lots of geothermal energy. That would reduce the need to rely on fossil fuels, wind, and solar power (which would be good, because fossil fuels lead to global warming, wind energy kills many birds, and solar farms generate lots of toxic waste. A Google-owned solar farm incinerates a thousand birds every year).
The Economist reported earlier on Fervo’s innovative approach:
George Mitchell, a scrappy independent oilman, is known as the father of fracking. Nearly three decades ago, he defied Big Oil and the conventional wisdom of his industry by making practical the hitherto uneconomic technique of pumping liquids and sands into the ground to force out gas and oil from shale rock and other tight geological formations. The enormous increase in productivity that resulted, known as the shale revolution, has transformed the global hydrocarbon business.
Now Fervo Energy, another scrappy Texan upstart, is applying such hydraulic fracturing—alongside other techniques borrowed from the petroleum industry—to the sleepy geothermal sector. Should it succeed, it would mean this relatively fringe source of energy could, in time, become a major player in the energy mix.
Geothermal energy typically taps underground heat by connecting to reservoirs of hot water or steam. But those reservoirs are found only in a few areas, which restricts the potential of conventional geothermal power. By contrast, “enhanced geothermal systems” (EGS), such as the one employed by Fervo, deploy hydraulic stimulation to create channels in hot rocks found across the globe. In 2023, Fervo conducted a successful pilot project in Nevada, and attracted Google as major customer. This June, Southern California Edison, a major utility, entered into a deal to purchase 320 megawatts of power from Fervo’s much larger new project in Utah, which seeks to use mass-manufacturing methods to use the technology it piloted on a vast scale. The deal is the biggest-ever purchase agreement for geothermal energy.
