Geothermal baseload and energy storage company, Sage Geosystems Inc, announced Christine, Texas, as the location for a 3MW Geopressured Geothermal System (GGS) energy storage facility after entering into a land use agreement with San Miguel Electric Cooperative Inc. 

Set to be established later in the year, near the SMECI lignite coal power plant, the EarthStore facility will utilise the earth's natural capacity for energy storage to produce clean, sustainable, and dispatchable electricity on demand. This technology offers a reliable and resilient power source that is independent of weather conditions and not reliant on wind or sunshine. 

“Once operational, our EarthStore facility in Christine will be the first geothermal energy storage system to store potential energy deep in the earth and supply electrons to a power grid,” said Cindy Taff, CEO of Sage Geosystems. “Geothermal energy storage is a viable solution for long-duration storage and an alternative for short-duration lithium-ion batteries. Electric utilities and co-ops like SMECI, will be able to use our technology to complement wind and solar, and stabilize the grid.”

The facility will use Sage’s proprietary technology to store energy, targeting 6-to-10-hour storage durations and delivering a round-trip efficiency (RTE) of 70-75%. In addition, water losses are targeted to be less than 2%. At scale, this energy storage system will be paired with renewable energy to provide baseload and dispatchable power to the electric grid. When combined with solar power, the facility will enable round-the-clock electricity generation at a blended Levelized Cost of Energy (LCOE) well under US$0.10/kWh.

Craig Courter, CEO, SMECI, said, “Long-duration energy storage is crucial for the ERCOT utility grid, especially with the increasing integration of intermittent wind and solar power generation. We are excited to be part of this innovative project that showcases the potential of geothermal energy storage.” 

Sage will operate as a merchant, buying and selling electricity to the ERCOT grid.

Sage will be applying for two drilling permits in Texas. The first permit is in Atascosa County for the EarthStore facility in Christine and the second permit is in Starr County, adjacent to the company’s existing test well.