Guest Editorial: Out of the West: Geothermal Opportunities Expand Beyond Historical Boundaries
Authors: Schmidt Brian , Pedersen Anine 
Published: January 2025

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Until relatively recently, harnessing geothermal energy in the US to meet power production and heating needs has been largely restricted to the western states.

The first geothermal production wells in this country were drilled in The Geysers, California, and much of the development since that time has similarly taken place in the west. As of 2021, the states of California and Nevada (combined) accounted for 85% of the country’s geothermal power plants and 93% of the installed capacity, with no geothermal plants being located any further east than New Mexico.

The reason for this is that exploiting geothermal energy in the conventional manner requires a very specific setting. Heat, fluid, and rock permeability must all be in abundance to utilize the Earth’s thermal energy. The western states’ geologic setting to the Pacific Ring of Fire results in several such locations.

However, advances in technology are opening opportunities in other parts of the country as well. Technological developments impacting geothermal include enhanced/engineered geothermal systems (EGS), closed-loop or advanced geothermal systems (AGS), and thermal energy networks (TENs).

Enhanced Geothermal Systems

EGS aren’t a new concept. The belief that areas with sufficient heat and moisture but lacking appropriate permeability could be engineered into viable geothermal reservoirs has been discussed for years, but recent developments are making this a reality.

In 2023, Fervo Energy announced a milestone in EGS development when a 30-day well test at their Project Red commercial pilot site demonstrated a flow rate of 63 L/sec at high temperature that enables 3.5 MW of electric production, setting records for both flow and output from an EGS.

The well test circulated fluid through the doublet system by pumping fluid down an injection well, through a fractured reservoir system, and up a production well. The injection pump located on the well pad provided all the pressure to drive fluid through the system with no need for a downhole pump or artificial lift system.

Sage Geosystems Inc. recently announced that it will partner with San Miguel Electric Cooperative Inc. to build the first geopressured geothermal system. The 3-MW EarthStore system will utilize the Earth's natural capacity for energy storage to produce dispatchable electricity on demand. Sage will operate as a merchant, buying electricity when production is plentiful, then storing it and selling back to the grid during periods of shortage. The facility, located in Christine, Texas, will use Sage’s proprietary technology to store energy, with a target storage duration of from 6 to 10 hours.

Utah's Frontier Observatory for Research in Geothermal Energy (FORGE) is an international field laboratory dedicated to developing and testing the methods and techniques required to create, sustain, and monitor enhanced geothermal systems resources. It is managed by the Energy & Geoscience Institute at The University of Utah and funded by the US Department of Energy. The project recently achieved a major breakthrough for the industry when circulation tests proved fluid flow and energy transfer from an EGS reservoir in hot, dry granite.