EDITOR’S NOTE: In the final installment in our series on geothermal energy, its availability in the West and the implications in Greater Yellowstone, Madison Dapcevich looks at the future of geothermal sites in Montana, sparking interest, and marrying the technology.
Montana State Hospital in Warm Springs has a long history of psychiatric treatment. Predating statehood in 1889 by 12 years, the state’s only public psychiatric hospital has served some of the Rocky Mountain West’s most vulnerable populations. But it was resource intensive and costly to heat water for the patients. Then, in the mid-20th century, the hospital began piping water from a natural hot spring was piped into the area for use in laundry and shower facilities. Since at least the 1980s, Montana has eyed the hospital for its hydrothermal and geothermal potential.
Water has historically been pumped to the state hospital from the nearby Fairmont Hot Springs, a 152-room resort 15 miles south that utilizes naturally heated water to warm its purported healing pools and buildings. Recently, private companies have been exploring the feasibility of installing geothermal power systems near the springs to generate electricity and pump hot water, reducing heating costs for local residents.
John Metesh, director of the Montana Bureau of Geology and Mines, says his agency is currently creating an inventory of geothermal sites around the state to do so.
“This begins by looking at data from oil and gas wells because these sites are very deep, and companies exploring for oil and gas can afford to conduct exploratory drilling,” Metesh said. “They’re drilling into geothermal formations to extract gas. So, the bureau looks at the data compared with seismic activity and geophysics data to build out maps of geothermal areas.” Between six and eight sites in Montana show potential to be transformed into geothermal power facilities, he added, one of which is the Montana State Hospital.
A previous estimation conducted in 2000 by Metesh and his colleague Jodey Kougioulis identified five areas that could be considered for geothermal development, including those near Bozeman, Ennis, Butte, Boulder and Camas Prairie.
Similar programs exist around the state. In 2020, Romney Hall at Montana State University launched a geothermal energy system, which efficiently cools and heats campus buildings and reduces their reliance on fossil fuels.
Aside from geothermal energy production through power plant facilities, hydrothermal features allow hot water to be pumped to nearby communities. Since the heated water is already close to the surface, it can be used as a hot water and energy source.
and Geology. Shown above are temperature and flow rate information for hot springs in the Deer
Lodge Valley, east of the town of Anaconda. Credit: MBMG
The Montana Bureau of Mines and Geology estimates roughly 150 springs and wells of low to moderate temperature could serve as potential geothermal resources, most of which are found in the southwestern part of the state. These abundant resources put the Treasure State in a unique position to become a major geothermal energy producer, particularly as its temperature extremes contribute to its place among the top five states with the highest per-capita energy consumption, according to the U.S. Energy Information Administration. Currently, coal accounts for 45 percent of Montana’s in-state power generation and about 30 percent of total U.S. coal production.
But like other alternative power generation proposals, Metesh says the reality of switching to geothermal energy comes down to the simple economics of its production cost versus its benefits.
“As traditional power costs increase and co-location of sources and transmission/use improve, geothermal will become more attractive, but the cost of [geothermal] production still needs to decrease,” Metesh said. “Montana, in general, has moderate potential for commercial geothermal in two broad categories: eastern Montana geothermal systems related to oil and gas development, and western Montana fault-controlled valleys.”
The Bureau of Geology and Mines is now conducting a new survey to identify potential geothermal sites across the state and has published the raw data on its website. In addition to pinpointing well locations, the Bureau of Geology and Mines is also cataloguing the geochemistry of known geothermal areas and their aerial geophysics, such as magnetism or radiometrics, which allows for a subsurface view of the Earth without needing to drill.
“It’s giving us a good idea of where we can narrow down the areas to look and eliminate some of the other areas – some of these formations are warm, but not quite hot and are at a lower threshold than what we’re looking for,” said Metesh, who estimates that the report will be out next year.
“Montana, in general, has moderate potential for commercial geothermal in two broad categories: eastern Montana geothermal systems related to oil and gas development, and western Montana fault-controlled valleys.”
John Metesh, director, Montana Bureau of Geology and Mines
Geothermal energy production requires three key components: surface water and shallow groundwater seeping deep toward the Earth’s heated interior. There, fluid warms to high enough temperatures to rise in fault lines as either hot water or steam, eventually reaching the surface. In shallow geothermal features like hot springs, accessing heat is relatively easy. But deep heat sources, those 10,000 feet and beyond, require large drills to access.
Current efforts by the Bureau of Mines and Geology pull available data from oil and gas exploration wells and seismic data indicative of fault-line fracture zones to “define and assess subsurface geology in areas that demonstrate higher-than-background temperatures.”
Angela Seligman, senior geoscientist at the nonprofit environmental organization Clean Air Task Force, notes that since extraction methods have recently improved, power plants can more easily access deep geothermal energy and produce energy from lower temperature resources more efficiently.
“We would like to think that all regions are thinking about geothermal energy as an important source of reliable electricity that is available 24/7,” Seligman said, “and that is also clean in terms of having little to no air pollutants like sulfur dioxide, particulate matter and greenhouse gas emissions.”
Metesh is optimistic about finding sites in Montana, sparking interest, and marrying the technology.
“As population grows and as demand for energy certainly grows, I think geothermal is going to become more and more important,” Metesh said.
Read Part 1 in our “Harnessing Earth’s Power” series here.
Read Part 2 in our “Harnessing Earth’s Power” series here.
