A friend once told Brian Regli that “we, Pennsylvanians” prefer to get our energy from the ground, not the sky.
Mr. Regli, now the executive director of critical investments with Gov. Josh Shapiro’s office, recently considered where that leaves us: a state rich in natural resources, peppered with holes in the ground, home to a skilled oil and gas industry in the middle of an energy transition.
“Boy, if we could figure out how to make geothermal work in Pennsylvania …” he said.
Geothermal energy, which uses heat from the earth to make electricity or warm buildings, has not been a hot topic in Appalachia in past years. It may not qualify as hot today either — although interest in repurposing abandoned oil and gas wells, or even drilling and fracking new wells to produce carbon-free energy, is certainly simmering.
“There is a global understanding that, ‘Hey, we got a lot of holes in the ground. Can we create revenue”‘ from something that would otherwise be a liability, Mr. Regli said.
He’d like to see a pilot project in Pennsylvania in the next few years. As would Arash Dahi Taleghani, professor of petroleum and natural gas engineering at Pennsylvania State University, who has written of “a symbiotic benefit” of reclaiming gas wells for geothermal development: “The oil and gas companies avoid the cost of abandonment, and the geothermal companies avoid the cost of drilling new wells.”
So far, the efforts to develop this industry in Pennsylvania have been mostly verbal.
But in recent months, a non-profit organization called Project InnerSpace has been reaching out to public officials, academics, and oil and gas interests in Pennsylvania, pitching a transition from fossil fuel extraction to geothermal energy using the same workers and, potentially, the same infrastructure.
In May, Trent McFadyen, director of strategic initiatives with Project InnerSpace, spoke to the state’s crude development advisory council, which is composed of conventional — i.e. not shale gas — operators.
CNX Resources Corp., a Canonsburg-based shale developer, has indicated it is looking at geothermal energy in some capacity, but declined to provide details.
Mr. Taleghani said he’s trying to get a project going at Penn State.
Until then, West Virginia University may be Appalachia’s proving ground for turning the geology and the tools of shale gas into geothermal potential.
Hot, dry rocks
Sam Taylor, director of WVU’s Institute for Sustainability and Energy Research, said he’s had geothermal in the back of his mind since he saw a subsurface heatmap of the U.S. in 2011. The map had several Western states drenched in red, while the Eastern U.S. wore mostly cool colors. Except for some yellow and orange blotches under the WVU campus near Morgantown.
“Maybe there’s something there,” he thought.
Coincidental proof of high temperatures came from a gas well at WVU’s Marcellus Shale Energy and Environmental Laboratory project, a working well site where researchers monitor various aspects of geology and gas production.
West Virginia University contracted with Northeast Natural Energy to drill a test geothermal well at Morgantown Industrial Park, Morgantown, WV.(Andy Travis)
Mr. Taylor said the temperature reading around the bottom of the well, which plunges some 6,500 to 7,000 feet, was 165 degrees Fahrenheit. It’s not enough to boil water, but it might be useful for heating buildings.
“Really, it’s warmer than you might expect,” he said.
On paper, it looked like a geothermal well drilled about two miles deep could heat the University’s campus.
This summer, with funding from the U.S. Department of Energy, WVU put drill bit to dirt. Initial data from the test well showed temperatures of 190 degrees, Mr. Taylor said, but deep analysis of the rocks hasn’t yet begun.
Geothermal wells in Western states, like California and Nevada, pull from hot, wet rocks. Water is already there, bubbling, and the wells bring it to the surface.
In Appalachia, the hot rocks are dry. So the idea is to use them like an oven.
One well would be used to pump water, or some other fluid like compressed carbon dioxide, into the formation where it will heat up. Another well will suck the heated fluid out and to the surface, where the heat will be transferred using a heat exchanger and the fluid, now cool again, will be pumped back into the first well to repeat the cycle.
“It’s kind of like a radiator system in your house,” Mr. Taylor said.
These hot dry rocks aren’t necessarily good sponges on their own and might require what’s being called enhanced geothermal recovery, a.k.a. fracking, to break up the rock and create space for water to flow through.
The West Virginia test well isn’t fracked. Even without it, the drilling costs alone amounted to $6 million. Another $6 million or so will be spent on testing and analysis, which is also being used to look for carbon storage horizons.
Cornell University in New York drilled a similar test well on its campus last year, concluding it would likely need to be fracked to make geothermal production possible.
Whose heat is it anyway?
Before any commercial development of geothermal energy can begin, stakeholders will ask the same question that has accompanied waves of resource extraction in Appalachia: Who owns geothermal heat?
Such considerations helped to create the tiered system of surface and subsurface ownership in this part of the country, where one person could own the mineral rights, another the coal, and another the land on the surface.
The recent enthusiasm for the development of carbon dioxide sequestration in the pores of deep rock formations in Pennsylvania and elsewhere has run into the same issue: Who owns the pore space?
“The same question keeps coming up again and again and again,” Mr. Taylor said.
West Virginia lawmakers passed a bill last year that says the surface owner also controls the pore space below. It said the same applies to geothermal resources. That determines who gets to agree to geothermal drilling and who gets royalties from it.
In Pennsylvania, the legislature has yet to address the subject.
