Millions of inactive wells are littered across the United States, remnants of an earlier era of fossil fuel production. A large number of sites have no official owners, and many are still polluting groundwater and leaking heat-causing methane. The country has hardly moved forward in dealing with this problem.
Policymakers in both Republican- and Democratic-led states are exploring whether these sites could be converted into new wells for geothermal energy production. After all, holes have already been drilled in the ground. And areas with extensive oil and gas development have the rich subsurface data that geothermal companies need to determine where and how they can build their carbon-free systems.
This concept is relatively new and largely untested, although scientists and startups are working to change that. States are also laying the groundwork for action by removing regulatory barriers and launching in-depth studies.
In Oklahoma, the state Senate is considering a bill that would create a process for companies to buy abandoned oil and gas wells and repurpose them for geothermal energy or underground energy storage. Oklahoma has identified more than 20,000 such wells, and state regulators estimate it would take 235 years and millions of dollars to plug them all. Fixing an old well can cost anywhere from $75,000 to $150,000 or more, depending on where it is located and how complex it is to clean, according to some estimates.
The Well Repurposing Act, which passed the Oklahoma House in March, is modeled after similar legislation that New Mexico adopted last year to address its more than 2,000 orphan wells.
The Oklahoma bill “recognizes that these wells are a liability, and there could be a way to turn them into some kind of revenue generation and give them value,” said Dave Tragethon, communications director for the nonprofit Well Done Foundation, which works to find and plug abandoned oil and gas wells across the country. “And if there is value, that means there is more desire to address them and more opportunity to raise money.”
In Alabama, legislators passed a law last month that allows the state to approve and regulate the conversion of oil and gas wells to harness alternative energy resources such as geothermal. North Dakota adopted a bill last year requiring a legislative council to study the feasibility of using non-productive wells to generate geothermal energy. And in Colorado, state agencies have launched a technical study to evaluate the potential for reusing old wells for geothermal development and carbon capture and sequestration.
These efforts reflect growing bipartisan support for geothermal energy, which has been largely untouched by the Trump administration’s efforts to block renewable energy projects. The energy resource has the potential to help meet the country’s growing energy demand, while also reducing planet-warming emissions from electricity and heating.
Converting wells is attractive but complicated
Geothermal systems work by circulating fluids underground to capture naturally occurring heat, which can be used to drive turbines to generate electricity or directly heat air and water in buildings. The industry is gaining momentum due to recent advances in drilling methods and technologies that are making access to geothermal energy technically possible or financially viable in more locations.
Many of those successes have come from the oil and gas industry, whose skilled workforce of drilling engineers and geologists and deep corporate pockets have helped spawn startups and deploy cutting-edge systems. However, most of that expertise and funding is being put into building new projects – not into figuring out how to retrofit leaky wells abandoned by previous generations.
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