Since prehistoric times, people have used hot springs, which are warmed by Earth’s mantle, for bathing and heating. Nowadays, geothermal energy is used to make electricity, producing over 10 gigawatts globally.
The U.S. leads the world in geothermal electricity production, and is home to the largest geothermal facility: “The Geysers,” located in Northern California. But geothermal contribution to the U.S. grid is still tiny when compared to places like the Philippines and Iceland, were geothermal energy makes up a substantial part of the national electrical production.
Geothermal power is reliable, sustainable, and environmentally responsible—but it has been historically limited by a scarcity of viable sources. Recent technological advances from the world of oil and gas exploration are beginning to lift accessibility obstacles.
Deep drilling techniques and aspects of hydrofracturing technology are being investigated as the basis for what is called Enhanced Geothermal Systems, or EGS. The idea is to mimic the natural processes that create hot springs by drilling deep beneath the surface, fracturing rock, and pumping water through it to capture heat.
A comprehensive study by MIT estimated that EGS could provide as much as 100 gigawatts of baseload electrical generation by 2050, equivalent to 200 coal-fired power plants or 100 nuclear power plants.
Much remains to be done with respect to the economics and environmental impact of Enhanced Geothermal Systems, but the earth beneath us could well become a primary source of energy.
The Future of Geothermal Energy
Photo, taken on July 27, 2011, courtesy of ThinkGeoEnergy via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY, with partial support from the Field Day Foundation.