When it comes to powering U.S. homes, oil and gas and geothermal energy are pretty similar: Both use comparable technologies and processes to locate and drill resources that generate electricity. Perhaps it’s not surprising, then, that one key step to unlocking the full potential of geothermal—one of the cleanest and most dependable forms of renewable energy—may lie inside millions of American oil and gas wells.
Old Tech, New Tricks
Geothermal energy captures the heat beneath our feet by harnessing hot water or steam from the earth to power electricity-generating turbines. Its production requires no fossil fuels, and the water can be injected back into the ground for reuse. Plus, geothermal energy isn’t dependent on weather, season, or time of day—it can be produced around the clock, all year long.
Although commercial geothermal electric-power production began in the United States more than half a century ago, geothermal accounts for just 0.4% of U.S. electricity generation, due to geographic, technological, and permitting limitations. Historically, geothermal electricity generation has been confined to areas with naturally occurring hydrothermal resources—heat in the earth, along with groundwater and rock characteristics (i.e., open fractures that allow fluid flow) sufficient for recovering heat energy. In the United States, those resources are found mostly in the West, leaving other regions with less potential for geothermal electricity generation.
That’s where our nation’s oil and gas wells can come into play.
Where There’s a Well, There’s a Way
There are two ways to produce geothermal energy inside existing oil and gas wells: the abandoned well process and co-production.
In the abandoned well process, water is pumped into the well, where it is warmed by the earth and then drawn back to the surface to power a thermoelectric generator. The resulting electricity can be used for heating, cooling, or to power nearby structures and homes. America has millions of abandoned, dry, or unproductive wells that could be used this way.
Co-production creates geothermal energy from oil and gas wells that are still active. Oil and gas wells often encounter extremely hot water, and co-production captures that heat to generate electricity that can be used immediately or stored for later use. Since the water is continuously recycled by injecting it back into the reservoir, co-production has a near-zero additional carbon footprint and can create wells that produce two types of energy simultaneously.
Even when subsurface temperatures are not hot enough for electricity production, geothermal energy can be tapped for direct use. Such uses include industrial processes (e.g., food drying) as well as heating and cooling of schools, greenhouses, and other buildings.
Investing in the Future
The U.S. Department of Energy Geothermal Technologies Office’s (GTO) GeoVision analysis found that geothermal electricity generation has the potential to increase at least 26-fold by 2050. Bringing more geothermal electricity online by leveraging existing oil and gas wells is a critical step to meeting the nation’s goals of a carbon-free electric grid by 2035 and net-zero emissions economy-wide by 2050.
To help advance geothermal research and development, DOE funds programs like the Wells of Opportunity (WOO): Amplify II & ReAmplify, which provides up to $14.5 million to establish the commercial viability of geothermal energy production in existing oil and gas wells.
To date, WOO has awarded more than $8 million to four projects dedicated to unlocking the full potential of geothermal power. These investments will expand U.S. geothermal energy capabilities and ultimately create clean energy jobs, while providing opportunities for oil and gas workers to transition to careers in the renewable energy industry.
Add all that up and you’ve got a lot more than just a hole in the ground.