A 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. Oil and gas wells can be used to harness geothermal energy in two ways: through the retrofitting of inactive or unproductive wells or co-production on active wells.  The U.S. Department of Energy’s (DOE) Geothermal Technologies Office (GTO) is investing in both with the Wells of Opportunity (WOO) initiative.

WELL RETROFITS

In well retrofits, an unused, dry, or unproductive oil and gas well first undergoes any repairs necessary for safe operation. Water is then pumped into the oil and gas well, where it is warmed by the earth and drawn back to the surface to power a thermoelectric generator.

• The hot water pulled to the surface can be used for heating, cooling, or to power nearby structures and homes. 
• America has millions of dry or unproductive oil and gas wells, many of which could be leveraged for geothermal use.

Note: The scope of GTO’s WOO initiative specifically targets inactive or unproductive wells. These wells may include those that qualify as abandoned according to the U.S. Environmental Protection Agency: wells that have been plugged to prevent migration of gas or fluids, wells with no recent production that are not plugged, and wells with no recent production and no responsible operator.

CO-PRODUCTION

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.  This electricity can be used immediately or stored for later use.
• Because 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. 

WELLS OF OPPORTUNITY (WOO) INITIATIVE

To help advance geothermal research and development, GTO funds programs like the WOO initiative. The initiative funds a number of projects under Pilot, Amplify, Amplify II, and ReAmp topic areas:

• Cyrq Energy, Inc. (Salt Lake City, UT) will use a combination of several innovative stimulation technologies to improve the permeability of well 16-29 at the Patua Geothermal Field in Churchill County, NV, in order to boost electricity generation at the power plant.
• Geothermix, LLC (Austin, TX) will harvest waste heat from existing oil and gas wells in Texas to generate commercial quantities of geothermal electricity.
• ICE Thermal Harvesting (Houston, TX) will produce electricity from 11 existing oil and gas wells in California’s San Joaquin Valley using an innovative power generation technology.
• Ormat Nevada, Inc. (Reno, NV) will sequentially stimulate three wells at three separate operating geothermal fields in Nevada to conduct a comparative analysis of similar stimulations in different geologic environments and increase production:
  • Don A. Campbell well 68-1RD in Mineral County, NV
  • Jersey Valley well 14-34 in Pershing County, NV
  • Tungsten Mountain well 24-22 in Churchill County, NV
• Transitional Energy (Aurora, CO) will install state-of-the-art, American-made geothermal heat engines at Blackburn Oilfield in Nevada for electrical power production. As a result of the project, Transitional Energy will generate geothermal energy at the site and construct new rural electric vehicle charging infrastructure.
• University of Oklahoma (Norman, OK) will produce heat from an Oklahoma oilfield for use in Tuttle Elementary and Middle Schools in Tuttle, Oklahoma. With access to four hydrocarbon wells within a mile, the schools will benefit from the ‘recycling’ of oil and gas infrastructure at considerable savings for the schools.

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.  

WOO is part of GTO’s Enhanced Geothermal Systems (EGS) Program. Learn more about other EGS efforts and GTO Priorities.