When people talk about the potential of “renewables” to lead us into a clean energy future, they are typically really referring to wind and solar power. These are currently the two biggest renewable sources of energy besides hydropower (which lacks scalability) and biomass (which isn’t actually clean). But more importantly, the plunging costs and near-unlimited scalability of these technologies make them front-runner candidates for the main energy sources of the future. But there is another contender whose immense potential is starting to be revealed: geothermal.
Geothermal is energy harnessed from the heat originating in the Earth’s core. There is enough energy inside the Earth to power the world many times over, but capturing it is difficult. As this article details, most geothermal energy that we currently use comes from heat that makes it all the way to the surface in the form of hot springs and geysers. But these kinds of sources are limited, which is why geothermal has been a small, niche energy source up to now.
But the technology to drill down into the earths crust and capture some of the trapped heat, called “Enhanced Geothermal Systems” (EGS) has been improving, largely thanks to the same horizontal drilling technology that enabled the fracking boom. While technological challenges remain, these methods can be applied more or less anywhere in the world. Geothermal energy also has the enormous advantage over solar and wind that it is reliably available any time of the day, negating the need for mass-scale energy storage or alternative (likely dirtier) sources to fill in the gaps.
In short, geothermal energy is poised for a breakout and could be a major part of a clean energy future. This is good news for Montana’s clean energy prospects. While Montana has lots of hydropower and the Eastern Plains have good wind energy potential, the state is relatively lacking in solar energy potential due to being so far north. But, as anyone who has visited our hot springs might guess, the state has solid geothermal potential. The map below from the National Renewable Energy Laboratory (NREL) shows geothermal potential for the whole country. The yellow dots are known surface-level geothermal sites that could be exploited for energy. Idaho, Nevada and Oregon are the American epicenter for these sources, but southwestern Montana has several of its own. Despite this, unlike most Western states, Montana does not have any geothermal power plants or any under development.
But the greater promise lies in sub-surface EGS. The map color-codes EGS potential, with darker shades indicating more. Montana’s western neighbors are again the leaders here, but the state has plenty of EGS potential of its own. Given the relative lack of solar energy, and the fact that EGS power can be spread around the state and not spoil any hot springs, it makes sense for Montana policy makers and clean energy advocates to make a strong push for EGS.
There’s another benefit of geothermal energy relevant to Montana. As I’ve written about before, fossil fuel industries have gone into decline, and the oil and gas industry lost 118,000 jobs during the pandemic. But if geothermal energy takes off, it could soak up some of the job losses from fossil fuels. And because geothermal energy involves a lot of drilling into the Earth’s surface, many of those working in fossil fuels will have skills that are directly transferable. The town of Colstrip, home to Montana’s largest but troubled coal power plant, happens to be near one of the state’s geothermal hotspots.