Sage’s Texas geothermal pilot loses less than 10 % of its water

A valve opens at the top of Sage Geosystems’ Texas system, releasing mechanical pressure built underground as hot water pushes against surrounding rock. The company’s first next-generation geothermal plant is now online as a pilot, and Sage says it lost less than 10 % of the water it cycled on multiple occasions.

The system works by creating a network of underground fractures, then pumping and storing large volumes of water in them. Unlike other enhanced geothermal projects, which use fractures to move water between two wells, Sage’s approach builds pressure and releases it through a valve. Water can migrate into nearby rock as it moves through the fractures; the less water lost, the more efficiently the project can produce energy.

That result matters because Sage says lower water loss should raise the net power output of enhanced geothermal systems and help them scale at a competitive cost. The Texas pilot also gives the company a way to model and predict how its underground reservoir will behave before it builds larger commercial facilities.

Sage is shifting its focus from energy storage to electricity production. It plans to drill its first well at one of Ormat’s conventional geothermal plants in Nevada later this year and supply the hot water to that existing facility. Sage expects the system to begin producing electricity in 2027 and reach full-scale production in 2028, although it has not specified its size.

So what changes in practice? A geothermal developer could test Sage’s pressure-based system without first connecting a new plant to the grid or building an entire power station. The company says it has about a gigawatt’s worth of projects on paper, including plans to work with Meta on 150 MW of next-generation geothermal power east of the Rocky Mountains. For now, the evidence remains pilot-stage: Sage’s water-loss figures come from its own Texas system, and the larger projects have not yet entered full-scale production.