By John McFerrin
Is geothermal energy a possible source of energy for West Virginia?
A modern society needs some way to produce electricity that is available all the time, not just when sun shines or the wind blows. In West Virginia, this perpetual availability—usually called base load—has mostly been provided by coal. As the availability of solar and wind power waxed and waned, coal was always there, chugging away, providing electricity.
Now that coal is in its dotage, West Virginia has begun to search for an alternative. A better system for storing electricity from wind and solar would make them into base load supply. That would take substantial advances in battery or other storage technologies as well as a substantial investment. Burning natural gas provides base load power but it also produces greenhouse gas. West Virginia has some untapped potential for hydro power. Nuclear power has its advocates, as well as those who feel just as strongly that nuclear power is a terrible idea. See the February, 2022, issue of The Highlands Voice.
But what of geothermal energy? It certainly has the potential to serve as a base load power source. Is it something that we should be considering?
Geothermal energy is, quite literally, heat from the earth. The earth’s core is made up of mostly molten iron with a temperature roughly equal to the surface of the sun. Were we able to tap even the smallest fraction of that energy we could meet the earth’s energy needs with plenty to spare.
The big difficulty is, or course, that the earth’s core is about 8,000 miles deep. All of that heat is not available.
With currently available technology, about the only places where any of that heat is being used for electricity production are power plants located near hot springs or volcanoes. There are places where water has been close enough to the earth’s core to become heated and has found its way through cracks in the earth’s layers until it is close to the surface. If it reaches the surface, it usually emerges as hot springs.
In spots where the hot water is close to the surface, the heat can be used to make electricity. As the end of 2019, the United States had over 3,600 megawatts of installed generating capacity of geothermal energy. All of it is in Alaska, Hawaii, and the Western states; there is nothing east of Colorado.
For spots where there is not enough heat to make electricity, there is a consolation prize. The warm, but not blazing hot enough to make electricity, water can be used to heat buildings. The city of Boise, Idaho, has used it to heat commercial and residential buildings since 1890 and still does so.
Technologically speaking, the electricity that is being produced so far is the easy stuff. The heat is fairly close to the surface and can be accessed with existing technology.
It is also limited by geography. Some people in California and Alaska were fortunate enough to live where hot water is close to the surface. They were clever enough to use that heat to make electricity. Those who are fortunate enough to live near a source of easily accessible geothermal energy have a ready supply of electricity free of carbon dioxide emissions.
What about the rest of the world, the large fraction of the Earth’s surface where there are no hot springs, no volcanoes, no relatively shallow sources of geothermal energy?
For the rest of the world, the geothermal energy is there. It is just a lot deeper and harder to get to. Until some technical problems are worked out, that energy is not available for human use.
There are possibilities on the drawing board. One is to drill two very deep (4-5 miles) holes and use hydraulic fracturing to connect them at the bottom. Water pumped down one hole would get heated. When it emerged from the other hole it would be hot enough to be used to make electricity. It is theoretically possible to build a closed system in which the holes from the surface are connected by a series of pipes. Water pumped through these pipes would absorb heat from the hot rocks and return to the surface as water hot enough to make electricity.
The technology still needs to be perfected before any of these techniques for geothermal energy from deep underground sources becomes a reality. Engineers have gotten a boost from the oil and gas industry; it already knows how to drill holes far into the ground. The oil and gas industry never had to deal with super hot water or super hot rock so the technology would not transfer perfectly but some of it would.
What about West Virginia?
On the face of it, it would appear that West Virginia would be a poor candidate for geothermal energy, at least of the kind that is accessible with current technology. While the more advanced methods for accessing geothermal energy would be possible anywhere, the readily available geothermal energy is usually found where there are hot springs or volcanoes. West Virginia does not have hot springs. With the exception of WVU head basketball coach Bob Huggins (a metaphorical, not an actual, volcano) we don’t have volcanoes.
The face of it, however, is not always right. Southern Methodist University has done some mapping of geothermal resources. On its maps, West Virginia is an anomaly for the Eastern United States. Among all the different colors indicating low temperatures, and thus little geothermal potential, there are some yellows and oranges in Northern West Virginia.
So, are we sitting on a gold mine, an easily accessible source of geothermal energy, a base load electricity source there for the taking? Nobody knows but we are about to find out. Researchers from West Virginia University are drilling a 15,000 foot hole near Morgantown. They will be able to collect data to tell us what the potential for geothermal electricity is.
With West Virginia’s lack of hot springs or volcanoes, finding the kind of relatively shallow geothermal energy that existing technology could turn into electricity is unlikely. The water and rock might not be hot enough. Even if the water and rock are not hot enough to generate electricity, it might be hot enough to provide heat to, for example, the buildings on West Virginia University’s campus.