A new method for capturing heat from low-temperature geothermal resources holds promise for generating virtually pollution-free electrical energy, according to scientists at the U.S. Department of Energy.
Researchers at the department's Pacific Northwest National Laboratory in Richland, Wash., will determine if their innovative approach can safely and economically extract and convert heat from vast untapped geothermal resources.
The goal is to enable power generation from low-temperature geothermal resources at an economical cost. In addition to being a clean energy source without any greenhouse gas emissions, geothermal could also a steady and dependable source of power.
"By the end of the calendar year, we plan to have a functioning bench-top prototype generating electricity," PNNL Laboratory Fellow Pete McGrail said in a news release. "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.
PNNL's conversion system will take advantage of the rapid expansion and contraction capabilities of a liquid called biphasic fluid. When exposed to heat brought to the surface from water circulating in moderately hot, underground rock, the thermal-cycling of the biphasic fluid will power a turbine to generate electricity. The fluid was developed by lab researchers.
--Eric Mortenson; firstname.lastname@example.org