The US Department of Energy (DOE) will award up to $18 million for 32 projects that will advance geothermal energy development in the United States. The selected projects target research and development in three technology areas: advancing subsurface analysis and engineering techniques for enhanced geothermal systems (EGS); applying a mapping approach called “play fairway analysis” to discover new geothermal resources; and accelerating extraction technologies to unlock domestic supplies of high-value materials like lithium from low- to moderate-temperature geothermal resources.
Together, these projects will lower the cost and risk of geothermal development, thereby accelerating technological advancement and economical deployment of geothermal energy.
Integrated EGS R&D ($10 million): Twelve collaborative enhanced geothermal systems (EGS) research and development projects will use novel techniques such as isotope studies, innovative rock mechanics experiments, and tracer studies integrated with geophysical methods, to increase the precision and accuracy of measuring critical underground reservoir properties over time.
EGS are engineered reservoirs, created beneath the surface of the Earth, where there is hot rock but limited pathways through which fluid can flow. During EGS development, underground fluid pathways are safely created and their size and connectivity increased. These enhanced pathways allow fluid to circulate throughout the hot rock and carry heat to the surface to generate electricity. Project teams will focus on laboratory feasibility studies in order to characterize critical EGS reservoir parameters—such as fracture length, fracture aperture, fluid flow pathways, and in-situ stress—in order to precisely engineer geothermal reservoirs.
These awards will later yield integrated characterization methods and prototypes ready to be validated in the field.
Play Fairway Analysis ($4 million): Play fairway analysis, a subsurface mapping technique already used for oil and gas exploration, helps to pinpoint where geothermal energy resources remain hidden beneath the Earth’s surface. Eleven projects will apply this analysis technique to identify prospective geothermal resources in areas with no obvious surface expression by detecting and plotting underground heat, permeability, and fluid to discover where all three are most likely to be present together.
Selected projects will study diverse territories across the United States—from as far west as Alaska’s Aleutian Islands chain and Hawaii, to the Cascade Range of Oregon, the Great Basin in Utah, the Rio Grande rift zone, and eastward to the Appalachian Basin in the mid-Atlantic region, where lower temperature geothermal resources could be tapped in the future. The resulting regional, basin-scale maps will serve to quantify and reduce uncertainty for geothermal energy exploration.
By improving success rates for exploration drilling, play fairway analysis could significantly lower the costs of geothermal energy while opening up new areas to development.
Low-Temperature Geothermal Mineral Recovery Program ($4 million): Geothermal brine has the potential to contain relatively high concentrations of rare earths and other valuable materials. This targeted initiative focuses on combining power generation with mineral extraction as a path to developing commercially viable, low- to moderate-temperature geothermal resources, while boosting production of materials needed by manufacturers of clean energy technologies and other industries.
Nine projects will focus on feasibility studies aimed at better understanding extraction technologies and process economics, assessing the current critical materials resource base, and researching and developing innovative extraction methods.