BOISE, Idaho — A U.S. Department of Energy report this spring made a bold prediction.
The nascent geothermal industry, it said, has a ready workforce of 300,000 engineers, hydrologists, drillers and power plant operators ready to tap right here in this country.
All that's needed are more early adopters like Tina Riley who are willing to move over from the oil and gas sector. After two decades as a geologist with ExxonMobil in Houston, she recently moved to Idaho to help run Boise's geothermal utility.
"Boise is really well known for geothermal and I wanted to become part of it," Riley says. "I really wanted to be part of the energy transition."
Geothermal energy, which in its simplest form means tapping hot water locked in granite faults sometimes thousands of feet below the surface of the earth to create heat or electricity, is often dubbed an invisible technology. It's long been seen as underutilized. But it's also a hugely expensive renewable resource to extract compared to more conventional drilling.
Nevertheless, the White House is launching an ambitious plan to increase its development in the United States by twenty fold. And its success relies partly on a very visible industry to achieve that — oil and gas.
Boise has the oldest geothermal system in the country
Today Boise leaders see their geothermal system as a key component to meeting the city's climate neutrality goals. Since 2000, it has reduced 100,000 CO2 equivalents, or roughly the same as taking 24,000 cars off city streets. But the heating system originally came online as a cost savings measure in response to the oil crisis in the late 1970s. Geothermal had even been used to heat homes in one of the city's more affluent neighborhoods for well over a century.
Today about a hundred buildings including a Veterans Affairs campus get their heat and hot water piped in from the geothermal aquifer beneath the city. The list also includes the Idaho capitol; the only state capitol building in the country to be heated by geothermal.
A short drive away, Riley is getting out of a city owned electric car and walking to check on one of the system's well houses. It's adjacent to a popular trailhead and mountain bike park. Most residents or visitors would have no idea it's even there, more evidence it really is a mostly invisible technology.
"What we're walking along now on this road is actually an inactive fault," Riley says. Idaho's geology makes it particularly suitable for geothermal energy, she adds.
Soon, two structures built into the side of the mountain come into view. They look like bunkers. The warm water is pumped up through these well houses into a pipe system then transferred underground to nearby downtown. After it's used, it's discharged back into the aquifer near the Boise River.
Riley beams as she adds that the system is closed loop, totally renewable and emissions-free.
"It's a form of energy that just checks so many boxes and it utilizes a lot of skill sets that are transferable or applicable from oil and gas," Riley says.
There is a lot of untapped potential with geothermal
Boise's system is only used for heat because the warm water in the geothermal aquifer beneath this city of 230,000 is below the boiling point. But in other areas, geothermal can also be used to generate electricity.
In fact, scientists believe there is enough of the resource underneath the lower 48 states alone to provide power to upwards of seven million homes. But transitioning all those workers over from oil and gas is still considered a long shot. Until recently, scaling up geothermal took a backseat due to advances in fracking for natural gas.
"Where the geothermal industry is today is where the oil and gas industry was 150 years ago," says Bryant Jones, executive director of Geothermal Rising, a trade group. "You drill for oil and gas where you literally saw oil and gas bubbling up from the surface."
That's partly why Boise's system is so developed because the resource is relatively easy to access. But there are movements afoot that could change this. Bi-partisan legislation that's gaining momentum in Congress would put geothermal on the same playing field as oil and gas when it comes to permitting and new exploration on federal land.
This could bring down costs, Jones says. The geothermal industry is a fraction of the size of wind, solar and oil and gas industries in the U.S., accounting for only .4% of the total electricity generation.
"Because of that small size we just don't have enough boots on the ground in state capitols or in Washington, D.C.," he adds. "So when policies are being discussed, geothermal is often left out."
This Spring the White House did announce $60 million to scale up geothermal, funding an initial round of pilot projects including one run by Chevron. In its report this year, the Biden administration pushes to expedite new drilling in Idaho and five other states by 2030, as part of its goal to create a carbon free electricity grid by 2035.
"Geothermal is a subsurface resource just like hydrocarbons. It requires pipes. It requires drilling. These are all skills and trades that we have in the U.S.," says Amanda Kolker, who runs the geothermal program at the federal National Renewable Energy Lab. "It's a much smoother transition to geothermal than to maybe some other technologies."
There is little data available beyond anecdotes about how many workers are actually transitioning or interested in moving to geothermal from conventional fossil fuels industries. Scientists at the Colorado lab have made gains in the last three years improving efficiency and drilling techniques but they're still far behind oil and gas.
Kolker calls geothermal exploration a very uncertain art: "Because if you can imagine, you're trying to understand what's going on underground. It's invisible, you can't see it, and your best data points are deep wells and we don't have lots of those."
Boise is looking to expand, cautiously
But geothermal is increasingly attractive because it's a stable renewable energy source. And the race has been on to find a suitable baseload fuel to supplement wind and solar.
In Boise, the former oil geologist turned geothermal manager, Tina Riley, says demand to join the city's system has grown by 25% just since 2020.
"It works around the clock, you don't have to worry about the wind or the sun shining," she says, talking over the loud hum of the pumps.
Riley says they're planning to expand slowly. They hope advancements in technologies will soon give them a better picture of exactly how much of the resource is available. But they are currently looking to add more than a dozen new buildings to the system soon.
For her part, Riley has no regrets about leaving the Texas oil patch.
"The really cool thing in my mind is that, oil and gas, as you use it, it's depleted. With a geothermal aquifer, you don't. It's a sustainable form of energy that's going to be around for many generations to come," Riley says.
