Geothermal energy could meet large
part of U.S. power need
Jan 23, 2007 The Associated Press
The nation could generate a large part of
the electricity it will need in the future by tapping
the enormous amounts of heat energy locked up in hard
rock below the earth's surface, a new Massachusetts
Institute of Technology-led study indicated Monday.
Heat mining could supply energy at competitive prices
and with minimal environmental impact, according to
the 400-page report commissioned by the U.S. Department
of Energy to assess the value of continuing to fund
geothermal energy study.
"We've determined that heat mining can be economical
in the short term, based on a global analysis of existing
geothermal systems, an assessment of the total U.S.
resource and continuing improvements in deep-drilling
and reservoir stimulation technology," said Jefferson
W. Tester, an MIT professor who led the 18-member
The United States is the biggest producer of commercial
geothermal energy in the world, with most of its plants
in California, Hawaii, Utah and Nevada. The systems
were the third largest source of renewable energy
in the nation in 2003, supplying electricity to some
2.8 million households, according to the Washington-based
Geothermal Energy Association.
The report said that's about as much as wind and
solar energy production combined, and it has potential
to be a steadier source.
Existing geothermal plants, however, are mainly
located in isolated regions of the west, where hot
rocks are closer to the surface, requiring less drilling
and lowering costs. Other areas could be commercially
viable because of improved technology, the report
The report recommended more detailed assessments
of hot rock deposits, field trials of geothermal energy
production sites and more research on the related
Environmental impact of geothermal energy is much
less than that of fossil fuels and nuclear energy,
though water requirements for geothermal plants could
be a problem in arid regions, the report said, and
the seismic risk also needs to be carefully monitored
Although the U.S. leads in global geothermal energy
production, it only gets less than half of one percent
of its power from that source, Geothermal Energy Association
Executive Director Karl Gawell said.
"Heat in the U.S. is an enormous resource," he said.
"We've just began to tap it."