enhanced

Steam produced by underground heat is an excellent source of clean energy. In a few fortunate places around the world – notably Iceland and New Zealand – people have been using this source of power for more than a century. In the U.S., a few places in the West have access to geothermal energy, and thus it provides roughly half-a-percent of the total U.S. power supply.

There is no shortage of underground heat but tapping into it is not so easy. Enhanced geothermal energy refers to drilling down to where the rock is hot and injecting water to be heated and thereby provide steam that is then used to generate electricity. According to the Department of Energy, there is enough energy in the rocks below the surface of the US to power the entire country five times over.

Recently, in northern Nevada, a company called Fervo Energy successfully operated an enhanced geothermal system called Project Red that generated 3.5 megawatts of clean electricity, the largest enhanced geothermal plant ever demonstrated.

There are now multiple start-up companies pursuing enhanced geothermal energy and the reason is somewhat ironic. Much of the research and development needed for new geothermal technologies has already been done by the oil and gas industry for their own purposes – notably fracking. Those industries have gotten extremely skilled at drilling into rock and such skills are what are needed for enhanced geothermal technology.

Enhanced geothermal faces some of the same challenges as drilling for gas, such as intensive water use and potential triggering of earthquakes. There are also issues related to permitting. But the urgent need for more sources of clean energy has made enhanced geothermal energy a potentially very valuable addition to our energy portfolio.

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Enhanced Geothermal Could Be A Missing Piece Of America’s Climate Puzzle

Photo, posted October 12, 2022, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The heat beneath the earth represents a vast repository of energy that in principle could provide for a significant part of our needs. In some places, geothermal energy is easy to get to and is already being exploited. California and Nevada operate dozens of geothermal electric generating plants. Boise Idaho heats 92 of its biggest buildings with the river of hot water that flows 3,000 feet below the city. In total, the U.S. produces enough geothermal electricity to power more than a million homes.

But all these examples make use of relatively rare local features that are not available to the great majority of locations. As a result, geothermal energy has generally not been viewed as being able to play a major role in the alternative energy transition.

A number of experts around the world disagree with this assessment. To a fair extent due to the deep-drilling techniques and knowledge about underground formations developed by the oil and gas industry during the fracking boom, there is growing interest in a type of geothermal energy called deep geothermal that accesses hot temperatures in the earth’s mantle as far down as two or three miles.

Deep geothermal can either access extremely hot water that exists down at those depths or water can be injected into hot rock down there, which is a technology known as enhanced geothermal systems.

There is enormous untapped potential for geothermal energy. A 2019 report by the U.S. Department of Energy says that by 2050, geothermal could provide 8.5% of the United States’ electricity as well as direct heat. Geothermal could be an important part of the so-called all-of-the-above future energy strategy.

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Can Geothermal Power Play a Key Role in the Energy Transition?

Photo, posted August 2, 2008, courtesy of ThinkGeoEnergy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Enhanced Geothermal Energy | Earth Wise

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Geothermal Power In The Energy Transition | Earth Wise

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