In this way, the heat from the volcano can be used to power the entire city

Active volcanoes are proving to be a hot commodity in the global race to transition to renewable energy, as regions around the world near these natural wonders seek to harness the heat they produce.

Geothermal energy, the process of using heat from the Earth’s inner core to create energy, is one of the most sustainable forms of energy, ABC News experts say. This technology involves pushing hot water from volcanoes and geysers to the surface, which then turns into steam under the influence of reduced pressure.

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The steam is then pushed towards a turbine, which then produces electricity.

Once the infrastructure is up and running, the process produces virtually no carbon dioxide emissions beyond the diesel-powered pump needed to bring water and steam to the surface, Pete Stelling, a professor emeritus of geology formerly at Western Washington University, told ABC News. .

“It’s considered the most sustainable source of energy,” Amanda Kolker, geothermal energy program manager at the National Renewable Energy Laboratory, told ABC News. “It’s also a relatively invisible renewable resource, both figuratively and metaphorically, because it’s literally underground.”

If any leaks occur in the pipes, the substance leaking is simply water or steam and no hazardous waste is produced, Jackie Caplan-Auerbach, a geology professor at Western Washington University, told ABC News.

Apart from land use and environmental damage caused by the initial construction, there are no other risks, Caplan-Auerbach.

“There are no refineries to build or transport to,” she said. “There is no gas station on the corner that needs to be developed to sell the product.”

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Stelling, however, said the objections to geothermal energy are troubling.

The technology is only available in select locations around the world. What makes a region ideal for harnessing geothermal energy is the availability of something “really hot” near the surface.

The vast majority are near active volcanoes, where an underground magma chamber heats the water around it, simply because those are the easiest places to find, Stelling said. He added that geysers and inactive volcanoes could also be a solution.

Residents and businesses that can benefit from geothermal energy must live near the plant because transporting the energy is not possible, Stelling said. Instead, the energy is placed directly into the power grid.

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In addition to determining whether cracks in the ground are large enough to allow water to flow, geologists must also consider the inherent risks of building an energy plant near an active volcano and whether a possible eruption could damage the plant, Caplan-Auerbach said.

Stelling said the biggest obstacle to installing geothermal energy plants is cost. Construction crews must drill several kilometers into the ground and extract hot water from open cracks in the ground. The turbine will then exhaust steam and generate electricity.

The construction project to bring geothermal energy to Unalaska, a city in Alaska’s Aleutian Islands, is expected to cost about $235 million to build a power plant powered by the Makushin volcano.

“The initial upfront investment is quite high,” Stelling said. “But once you get the equipment ready and the geothermal field is established, it works really well. And it’s really cheap.”

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Bringing geothermal energy to communities can lower energy costs for residents and businesses, especially in Alaska, which relies so heavily on imported oil for heating and electricity, Stelling said. The wind in the Aleutian Islands is so strong that it “simply tears apart the turbines,” preventing wind energy production, he added.

According to the Department of Energy, geothermal energy currently produces about 3.7 gigawatts of electricity in the United States. A new analysis found that geothermal energy could deliver 90 gigawatts of “stable, flexible power” to the U.S. grid by 2050.

Many people living near geothermal plants may not know that their cities are powered by the earth’s heat, Kolker said. For example, San Francisco at one point got a third of its power from its geysers, which are the world’s largest geothermal complex. In the geysers located in the Mayacamas Mountains, 120 km north of the city, there are 18 geothermal power plants drawing steam from over 350 wells.

The U.S. Department of Energy is currently examining the extent of the geographic limitations that geothermal energy poses, Kolker said.

“Efforts are underway to expand the geographic opportunities for geothermal energy using more unconventional approaches,” she said.

The Department of Energy announced Wednesday funding of up to $74 million for up to seven pilot projects that will test the effectiveness and scalability of improved geothermal systems.

“Advances in improved geothermal systems will help bring geothermal energy to regions where until recently it was considered impossible to use this renewable energy source,” U.S. Secretary of Energy Jennifer M. Granholm said in a statement. “These pilot demonstrations will help us realize the enormous potential of the heat beneath our feet to deliver clean, renewable energy to millions of Americans.”

This is how heat from a volcano can power an entire city. Originally published on abcnews.go.com