When they hear the word geothermal, most people think of superheated steam and water flowing near the surface, usually located near areas of volcanic activity. Of course, such valuable heat sources can only be found in certain places. Investors are moving rapidly to exploit high-temperature geothermal resources.
A new field of research and development — enhanced geothermal systems — brings hope that the reach of geothermal power generation can be extended even to states like Maryland.
Existing oil and gas drilling techniques can reach depths where moderately hot rock can be found at most places in the United States. Water is injected and the heat brought to the surface.
What’s needed are improvements to existing technology — for drilling, for “fracking” the hot rock and for improving the power generation potential of low-temperature turbines.
A new method for capturing significantly more heat from low-temperature geothermal resources holds promise for generating virtually pollution-free electrical energy. Scientists at the Department of Energy’s Pacific Northwest National Laboratory will determine if their innovative approach can safely and economically extract and convert heat from vast untapped geothermal resources.
“By the end of the calendar year, we plan to have a functioning bench-top prototype generating electricity,” predicts PNNL Laboratory Fellow Pete McGrail. “If successful, enhanced geothermal systems like this could become an important energy source.” A technical and economic analysis conducted by the Massachusetts Institute of Technology estimates that enhanced geothermal systems could provide 10 percent of the nation’s overall electrical generating capacity by 2050.