The upper six miles of Earth’s crust holds 50,000 times more energy than all of the world’s oil and gas combined, and US researchers are figuring out how to utilize that potential energy source.
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| Steam rises from the Calpine steam power plants located on a ridge at The Geysers on April 28, 2014, near Healdsburg, California. | George Rose/Getty Images |
While The Geysers have been producing electricity for a century, the site — the largest geothermal power system in America — may also be a precursor for a major future source of American clean energy. The move to boost the facility’s capacity using local wastewater, taken several years ago, symbolizes the kind of innovation engineers and scientists are now pushing hard to develop in a bid to unlock the enormous quantities of energy stored beneath Earth’s crust.
New technology, proponents hope, will cut costs and allow geothermal power to compete with solar, wind, and hydroelectric as a top source of American clean energy.