A multi-year enhanced geothermal system pilot launches in Utah to evaluate commercial viability and resolve unknown variables for long-term EGS production.

A four-month test of enhanced geothermal systems (EGS) performance aimed at derisking the technology for commercial viability began in Utah earlier this month, according to the Frontier Observatory for Research in Geothermal Energy (FORGE). Managed by the University of Utah and funded by the U.S. Department of Energy, FORGE announced in an Aug. 12 release that the initiative is an “extended circulation” designed to “evaluate reservoir performance under continuous flow” over 90 days, with potential extension to 120 days.

The trial will enable researchers to study “heretofore unknown variables required to ensure long term EGS production remains commercially viable,” said Kristie McLin, FORGE’s principal investigator. “Although major advancements have been achieved in the past few years, there is still a great deal we do not know about thermal breakthrough and water loss over time,” McLin added.

On its website, the DOE characterized the extended circulation test as “a significant feat,” noting that “only a handful of EGS projects worldwide have reached this stage … [The test is the] culmination of years of federally funded work and can hold the key to some of the most important steps to advance EGS.”

Despite these advances, enhanced geothermal systems remain in the early stages of commercialization. EGS developer Fervo Energy’s 500-MW Cape Station stands as the first commercial-scale EGS project in the United States and is expected to begin delivering power to the grid later this year. Fervo Energy went public via a May IPO, though its stock has since fallen 56% from its initial peak. During the company’s second-quarter earnings call, management cited “new but temporary, transmission-related curtailment issues for 2027, prompting us to lower FY27 revenue [estimates]” to $63 million from a prior projection of $79 million, according to an Aug. 14 research note by Jefferies equity analyst Julien Dumoulin-Smith.

Addressing the operational challenges, Fervo CFO David Ulrey stated during the earnings call: “The simple fact is, for our projects, there are things within our control and there are things outside our control. This is not new to power development, and it is not unique to Fervo … We feel really good about the things within our control. Our ability to drill hotter, faster, deeper, and cheaper is an enormous mitigant to a host of factors on our risk register.”

Looking ahead, McLin noted that while FORGE’s recent achievements “over the past few years have been very beneficial to the industry … there is still so much we do not know.” She concluded that the extended circulation test “will provide answers to the pressing questions about thermal decline and water loss, allowing geothermal companies to continue growing and to flourish.”