New Startup Aids Texas’s Geothermal Boom

Sage Geosystems, a geothermal baseload and energy storage company founded by former Shell executives, announced earlier this month that it’ll launch a geopressured geothermal system (GGS) called EarthStore in Texas later this year—the world’s first storage project to use the Earth’s natural capacity to store energy without relying on wind or solar.

Sage entered a land use agreement with the San Miguel Electric Cooperative earlier this month for the 3 MW geothermal storage facility and hopes to turn it on next year.

What is a GGS? It’s basically a battery buried in rock. Here’s how it works →

• Geothermal energy is usually hot water extracted from the Earth’s crust, but Sage is depositing the water as storage and experimenting with a custom turbine.
• The project will generate heat without the risk of “dry holes,” or wells that don’t have as much water as expected.
• The EarthStore Storage Facility will target 6- to 10-hour storage durations with a round-trip efficiency of 70-75%, according to Sage.

Zoom out: This initiative is part of a recent boom in Texas-based geothermal energy startups like Bedrock Energy, Quaise, and Fervo looking to capitalize on the state’s location atop significant reserves of subterranean heat.

By the numbers: The US geothermal market is still young—it only accounted for about 4 GW of the nation’s total renewables capacity of 148 GW last year. However, it could provide up to 90 GW of US clean energy by 2050, according to a federal analysis.

Still, there are challenges utilities and geothermal developers have to consider: up-front costs of up to $5 billion, unpredictable facility life cycles, and local community opposition, to name a few cited by the DOE.