While states seek In search of much-needed supplies of clean, reliable energy, some are turning to an unconventional source: abandoned oil and gas wells tapped for geothermal heat.
Millions of inactive wells are littered across the United Statesrelics of earlier eras of fossil fuel production. Many of the sites have no official owner, and many continue to pollute groundwater and leak heat-trapping methane. The country has barely scratched the surface of the solution to this problem.
Policymakers in states led by Republicans and Democrats are studying the possibility of converting these sites into new wells to produce geothermal energy. After all, the holes are already drilled into the ground. And regions with extensive oil and gas development have rich underground data that geothermal companies need to determine where and how to build their carbon-free systems.
The concept is relatively new and largely untested, although scientists and startups are interested in it. work to change that. States are also preparing the ground for action by removing regulatory hurdles and launching in-depth studies.
In Oklahoma, the state Senate is considering a Invoice it would create a process for companies to purchase 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 hundreds of millions of dollars to plug them all. Repairing a single old well can cost anywhere from $75,000 to $150,000 or more, by some calculations, depending on where it is located and the complexity of the cleanup.
The Well Repurposing Act, which passed the Oklahoma House of Representatives in March, is modeled after a similar law that New Mexico adopted last year to address its more than 2,000 orphaned wells.
Oklahoma’s bill “recognizes that these wells are a liability and that maybe there’s a way to turn them into some sort of revenue generation and give them value,” said Dave Tragethon, communications director for the nonprofit. Well-made foundationwhich works to find and plug abandoned oil and gas wells across the country. “And if there’s value, that means there’s more willingness to address them and more opportunities to raise money.”
In Alabama, lawmakers passed a law last month, which allows the state to approve and regulate the conversion of oil and gas wells to exploit alternative energy resources like geothermal. North Dakota adopted a bill last year, requiring a legislative council to study the feasibility of using non-productive wells to produce geothermal energy. And in Colorado, state agencies launched a technical study assess the potential for reuse of old wells for geothermal development and carbon capture and sequestration.
These efforts reflect growing bipartisan support for geothermal energy, which has widely remained unharmed by the Trump administration’s efforts to block renewable energy projects. This energy resource has the potential to help meet the country’s growing energy demand while reducing electricity and heating emissions that contribute to global warming.
Well conversion is attractive but complicated
Geothermal systems work by circulating fluids underground to capture natural heat, which can then be used to drive turbines to generate electricity or to directly warm the air and water in buildings. The industry is gain momentum thanks to recent advances in drilling methods and technologies that make access to geothermal energy technically possible or financially viable in more locations.
Many of these breakthroughs have come from the oil and gas industry, including qualified workforce drilling engineers and geoscientists, as well as wealthy corporations, helped launch startups and deploy state-of-the-art systems. However, most of this expertise and funding is devoted to building new projects, without seeking to retool the leaky wells left behind by previous generations.
“Oil and gas well conversion presents a huge opportunity, but it’s quite far from being a reality technologically,” said Emily Pope, a geologist and senior researcher at the Center for Climate and Energy Solutions, author of a book on oil and gas well conversion. recent study on new generation geothermal energy.
“There are some obstacles that are still quite immense,” she said, adding that “it’s worth doing the R&D to try to grow.”
One of the biggest challenges is that oil and gas wells tend to reach relatively low to medium underground temperatures. But high heat is essential for geothermal projects, especially those that produce electricity. THE the hotter the resourcethe more energy a developer can extract from the system.
Additionally, fossil fuel wells typically produce lower volumes of liquid and gas than geothermal wells need to spin power turbines or transfer heat to buildings. Geothermal operators may also need to take additional steps to prevent harmful elements from underground reservoirs from mixing with the working fluids used to extract heat from underground, said Arash Dahi Taleghani, an engineering professor at Pennsylvania State University’s Repurposing Center for Energy Transition.
He added that the high cost of converting wells to geothermal energy has so far limited the number of concrete examples.
Early research efforts target direct-use heat and storage
However, at the University of Oklahoma, researchers having evaluated how to turn four old oil and gas wells into geothermal heat sources, which they hope to pipe to public schools and nearby homes in the town of Tuttle. The project was reward a $1.7 million grant from the U.S. Department of Energy’s Wells of Opportunity program in 2022, although it was suspended last year during the Trump administration’s sweeping federal funding freeze and is still waiting to begin its next phase, KGOU reported in March.
Saeed Salehi was the director of the Oklahoma project before joining Southern Methodist University as an engineering professor in 2024. He said repurposing wells for geothermal has several “obvious benefits.”
Geothermal companies can avoid significant upfront drilling costs if the wells are already deep enough and hot enough. Oil and gas companies, which today pay millions of dollars to properly seal and cap modern wells, can instead give their assets a second life. And communities near aging fossil fuel infrastructure could benefit from clean, affordable heating and lower utility bills in winter.
“We need to collect enough data and have enough successful projects to scale it,” Salehi said, calling reused wells “a customized solution for specific regions and areas.”
“Everything is going to take time, but I think we are moving in the right direction,” he added.
A smoother permitting process will be key to speeding things up, something Oklahoma, Alabama and other states are aiming to address. States traditionally lack a regulatory framework to manage decades-old wells for which no one is technically responsible. Salehi said it took nearly nine months to get permits for the Tuttle project, although the process is now speeding up.
In Pennsylvania, Dahi Taleghani said his team is seeking funding to reuse old wells to supply the Penn State campus with geothermal heating. They also have studied the potential for using some of the state’s more than 200,000 abandoned wells to heat agricultural greenhouses, as well as to house energy storage systems that compress the air and hide it undergroundacting as low-cost grid batteries.
“The decommissioning of wells is costly, costly and generates no revenue,” Dahi Taleghani said. “So we’re looking to help create companies that can tackle these leaking wells, repair them, and then use them for geothermal applications.”
This story was originally published by Canarian media and is reproduced here as part of the Climate office collaboration.