Sage Geosystems Generates Power at Its First EGS Pressure Geothermal Plant: 3 MW Pilot Plant Performs Reliably and as Expected After Four Months Online

      In mid-August, Sage Geosystems announced that its first enhanced geothermal system (EGS) plant had been reliably generating power since April at its 3MW pilot plant near San Antonio, Texas. South Texas has sufficient subsurface heat for potentially economical geothermal power production. It is only the third EGS plant to come online in the U.S.

     After 120 days of grid connections, the plant produced reliably, and as expected, the company noted in an exclusive story for Canary Media in August:

“Cindy Taff, Sage’s CEO, said the results will ​“directly inform and de-risk” an upcoming collaboration in Nevada with Ormat Technologies, a conventional geothermal leader that is increasingly dipping its toes into next-generation technology. The Nevada project is a necessary precursor to Sage’s deal with Meta to develop 150 MW of geothermal power.”

“Sage’s enhanced geothermal system is a type of nascent tech that involves drilling deep into hot rocks and fracturing them to create water pockets, then using the heat to generate power. It’s distinct from the decades-old traditional geothermal plants that rely on what Taff called ​“very unicorn geology” — the few places in the world where a combination of water, heat, and permeable rocks are easily accessible.”

     It is the third EGS project online at a small scale. However, Fervo Energy is expected to turn a part of its overall 500 MW project online later this year.

     One measure of technical success for the hydraulically fractured or engineered reservoir is the low water loss. Thus, it appears the induced fracture system is contained, which bodes well for similar geology and for the industry in general. The company noted less than 10% water loss when it cycled water through the system on multiple occasions. This is expected to help the economics of EGS projects.

“The net power output that you can produce from these technologies is going to go up, she said, noting that curbing water loss will enable enhanced systems to scale commercially at a competitive cost.

     Apparently, Sage changed its plans from long-duration geothermal energy storage of heat to an approach that would produce power directly. They shifted due to Texas’s already abundant and still growing lithium-ion energy storage industry.

     Its next project in Nevada is a collaboration with Ormat at one of its conventional geothermal plants. Sage expects to drill a well and provide hot water directly for Ormat’s existing plant. That allows it to focus solely on its technology and apply it to an existing plant. Future plans in 2028 or later include a 150 MW plant in collaboration with Meta, somewhere east of the Rocky Mountains.

     Sage calls its hot dry rock geothermal process ‘pressure geothermal.’  Below are both its two-well power production model and its one-well energy storage model.

References:

 

Sage Geosystems brings its first next-gen geothermal plant online: It’s only the third such project to hook up to the U.S. grid. It comes as surging electricity demand drives interest in the source of around-the-clock clean power. Maria Gallucci. Canary Media. August 19, 2026. Sage Geosystems brings its first next-gen geothermal… | Canary Media

Hot Dry Rock Geothermal Power Generation Estimates for the USA (L48) Using Reduced Order Physical Models. Parker Anderson, Mike Eros, Samuel Klarin, Lev Ring, Douglas Simpkins. PROCEEDINGS, 50th Workshop on Geothermal Reservoir Engineering. Stanford University, Stanford, California, February 10-12, 2025. Hot Dry Rock Geothermal Power Generation Estimates for the USA (L48) Using Reduced Physical Models

Sage Geosystems. Website. Technology - Sage Geosystems