USGS Estimates Substantial Potential Power Generation from Domestic Geothermal Resources

October 8, 2008 // Published as a news service by IHS

The results of this assessment show that the U.S. has an estimated:

• 9,057 megawatts-electric (MWe) of power generation potential from domestic, conventional, identified geothermal systems.
• 30,033 MWe of power generation potential from conventional, undiscovered geothermal resources.
• 517,800 MWe of power generation potential from unconventional (high-temperature, low-permeability) Enhanced Geothermal Systems (EGS) resources.

The results indicate that full development of the conventional systems alone could expand geothermal power production by approximately 6,500 MWe, or about 260% of the currently installed geothermal total of more than 2,500 MWe.

According to USGS, the resource estimate for unconventional EGS is more than an order of magnitude larger than the combined estimates for both identified and undiscovered conventional geothermal resources and, if successfully developed, could provide an installed geothermal electric power generation capacity equivalent to about half of the currently installed electric power generating capacity in the U.S.

Results of this USGS assessment indicate that the power generation potential from identified geothermal systems range from 3,675 MWe (95% probability) to 16,457 MWe (5% probability); the power generation potential from undiscovered geothermal systems range from 7,917 MWe (95% probability) to 73,286 MWe (5% probability); and the power generation potential from EGS resources range from 345,100 MWe (95% probability) to 727,900 MWe (5% probability).

The nearly 15,000 gigawatt-hours (GWh) of geothermal power generated in 2005 constituted 25% of domestic nonhydroelectric renewable electric power generation (a little over 4,055,400 total GWh of electricity were produced in the U.S. in 2005).

The USGS assessment evaluated 241 identified moderate-temperature (90 to 150 degree Celsius; 194 to 302 degree Fahrenheit) and high-temperature (greater than 150 degree Celsius) geothermal systems located on private and public lands.

Geothermal systems located on public lands closed to development, such as national parks, were not included in this assessment, said USGS. Electric-power generation potential was also determined for several low-temperature (less than 90 degree Celsius) systems in Alaska for which local conditions make electric power generation feasible.

The assessment also included a provisional estimate of the power generation potential from the application of unconventional, EGS technology.

This assessment benefited from cooperation with the U.S. Department of Energy (DOE), U.S. Bureau of Land Management, the University of Nevada - Reno, the University of Utah, DOE Office of Nuclear Energy Idaho National Laboratory, DOE Lawrence Berkeley National Laboratory, state and local agencies and the geothermal industry.

To learn more about USGS National Geothermal Resource efforts visit the USGS Energy Resources Program web site.

Source: U.S. Geological Survey (USGS).