Penn State researchers have discovered a proposed geothermal-assisted compressed-air energy storage system (CAES) that uses depleted oil and gas wells can improve efficiency by 9.5 percent when compared to existing technology.
Increased efficiency means a larger percentage of energy stored in the system can be recovered and turned into electricity.
“This improvement in efficiency can be a game changer to justify the economics of compressed-air energy storage projects,” Arash Dahi Taleghani, Penn State professor of petroleum and natural gas engineering at and corresponding author a study recently published in the Journal of Energy Storage, said. “And on top of that, we could significantly avoid the upfront cost by using existing oil and gas wells that are no longer in production. This could be a win, win situation.”
The research was part of Penn State’s Repurposing Center for Energy Transition that seeks to repurpose the fossil energy infrastructure for energy transition applications, and is supported by the U.S. Department of Energy.
CAES plants compress air and store it underground when energy demand is low, and extract air to create electricity when demand is high. By reusing depleted oil and gas wells, operators would have access to geothermal heat which would eliminate the cost of drilling new wells.