Can geothermal energy finally take a bite out of climate change?

Dave Levitan

Source Link

In 2009, geothermal energy was having a moment.

Reports proliferated on tapping the massive potential of all that emissions-free energy deep within the Earth, which when brought to the surface can heat buildings or spin a turbine to generate electricity. President Obama listed geothermal right alongside solar and wind power in speeches; the American Recovery and Reinvestment Act sent $368 million in geothermal’s direction. Google started throwing millions of dollars at research and startup companies, going so far as to call new types of geothermal power “the ‘killer app’ of the energy world.” The search giant guessed that geothermal power could provide 15 percent of the country’s electricity by 2030.

And then … crickets.

“In terms of what is being built in the world, geothermal is completely insignificant, completely irrelevant right now,” said Jamie Beard, the founder and executive director of a nonprofit called Project Innerspace that is trying to reverse that irrelevance.

The energy source has a lot to recommend it, after all. It’s clean and emissions-free, and unlike wind and solar power it is considered “baseload” power, meaning it is always on. A geothermal power plant doesn’t take up the space that other renewables do either, making it more palatable to environmentalists worried about land-use changes.

Today there is undeniably an increasing amount of excitement and activity in the geothermal space, but its actual contribution to the world’s energy mix — and by extension, the fight against climate change — remains more or less flat. In 2012, geothermal accounted for a bit under half of one percent of American electricity generation, at 15.6 billion kilowatt-hours; in 2021, that number was 15.9 billion, and beyond a few demonstration projects no major geothermal construction is ongoing now. The U.S. leads the world in installed capacity, but that capacity is not all that different from what the country had 30 years ago.

So what’s going on? Why aren’t we building geothermal power?

“What is holding geothermal back is more social,” said Bryant Jones, executive director of the nonprofit industry group Geothermal Rising. “It is a lack of policy attention by governments at the federal level and state level. Those are social hurdles to overcome for the geothermal industry.”

At least part of those social blocks arise from geothermal’s long and somewhat boring reputation. The basic technology is quite old — Boise, Idaho, began circulating hot underground water to heat the city’s buildings in 1892. (They still use it, with 20 miles of piping heating six million square feet of building area.) The first geothermal power plant came on line in Italy in 1904; most of the 70 or so American geothermal power facilities came on line decades ago. And though technological advances have created some vast new potential for the field, it doesn’t seem to have quite the cachet of other clean tech.

But with climate change starting to spiral toward some particularly dire thresholds and landmarks, and global emissions trajectories that have the world far off track to stave off catastrophe, many think geothermal’s time has come. The question for the rest of this decade and beyond, then, is whether the industry can rise out of its stagnation and make a real dent.

Limitless potential

The main thing to know about geothermal energy is that there is a lot of it. The heat of the earth’s core extends outward into the crust, and only a few miles below our feet there is power galore. If we could harness just two percent of the energy found between two and four miles under ground, that would offer up to more than 2,000 times the energy the U.S. uses in a year. Zooming out further, one estimate suggests that even a tenth of a percent of the earth’s overall heat content is equivalent to all of humanity’s energy needs — for two million years.

The problem is moving the heat from down there to up here. The existing geothermal energy capacity around the world is in a few very select locations, where for various geological reasons the heat content of the planet has found its way up toward the surface. Places such as Iceland, or parts of the western U.S., won a bit of a geothermal lottery, where simply building infrastructure around hot springs and other geological fissures allowed the energy to flow. Those “conventional” geothermal resources are more or less tapped out, in terms of new development, which is why the stats have stayed flat for so long.

“It’s a naturally occurring, very easy to develop type of geothermal resource that occurs in very few places of the world. And because of that, it’s not very scalable,” Beard told Grid. “All kinds of stakeholders have dismissed geothermal because of the view that it is indeed geographically limited and therefore niche-y and not really relevant.”

Enter — strangely enough — the shale gas boom. The explosion in fracking and other unconventional drilling techniques beginning in the early 2000s spawned a rush of technological innovation, and it turns out that a lot of that tech is largely transferable to the geothermal world.

“If we take all of that advancement from oil and gas industry, transfer it into geothermal, what does that enable now?” Beard asked. “The answer is a lot — a hell of a lot.” A recent report on the potential of geothermal energy in Texas, authored by experts across five universities as well as the International Energy Agency, put a number on what the oil and gas tech transfer could do: as much as a 43 percent cost reduction for geothermal projects.

Enhanced or engineered geothermal systems (EGS) take advantage of those technological advances. Though the industry may be loath to use the word given its baggage, EGS is akin to fracking. It involves an injection well, into which cold water is pumped. The water then flows through induced fractures in the rock, heating up as it goes thanks to the ambient heat around it; the warmed water is then taken up in a separate pipe where it flows up to the surface, hot enough to turn a turbine and generate electricity or just heat a building. Fracking, but without the mess of chemicals that are brought back to the surface and not-so-occasionally spilled, and most importantly, without the end result of a hydrocarbon ready to be burned and emit greenhouse gases.

That’s the idea, anyway. “There are no commercial EGS projects in the world because we haven’t been able to make the cracks where we want to make them,” said Joseph Moore, a professor at the University of Utah and principal investigator at Utah FORGE, a dedicated geothermal field laboratory sponsored by the Department of Energy.

FORGE, situated in a barren stretch of land about 200 miles south of Salt Lake City, is overseeing the demonstration of an EGS project, and is collaborating with a number of private companies at the site as well. But for an industry that touts its potential to be built more or less anywhere, the promised expansion seems slow to arrive.

“We need more of those demonstrations funded, and FORGE is a really good example,” said Jones, of Geothermal Rising. “But it’s just one, and that’s all geothermal has.”

On the cusp

One might be forgiven for doubting the latest boom cycle after the false starts of the 2009 era, but there is an undeniable momentum to the geothermal field even though no major construction is yet underway.

“This is the geothermal decade,” Jones told Grid. “The interest in geothermal is exploding.”

Last month, Secretary of Energy Jennifer Granholm visited Utah to hear about the work going on at FORGE, and to announce a new round of funding — $74 million for up to seven pilot projects that “will test the efficacy and scalability of enhanced geothermal systems.” The ongoing research is key, Moore explained, because the tech transfer from the oil industry isn’t seamless — the drill bits and piping and connectors and so on need to operate at higher temperatures in the geothermal field.

“If you’re going to develop large-scale enhanced geothermal systems, you need to de-risk the tools,” he said, adding that the industry the tools come from doesn’t yet have the incentive to do so itself. “The oil and gas industry does not need these tools at the temperatures we need them.”

Big oil has started to show more interest, though, and a nascent geothermal industry is also starting to sprout. More than 20 startups in the field have popped up in the last couple of years, and more than a billion dollars in investments have flowed toward them. Some seem to be making legitimate progress.

For example, a company called Eavor features a slightly different form of technology called closed-loop geothermal, where heat flows between parallel pipes far under ground without a need to fracture the surrounding rock. Eavor recently announced success with a demonstration project in New Mexico, where they drilled a two-leg well down to 18,000 feet. Temperatures at that depth reached 250 degrees Celsius (482 degrees Fahrenheit) — the hotter it gets, the more power you can generate, which brings costs down. The Department of Energy’s Enhanced Geothermal Shot program has set a goal of cutting those costs by 90 percent by 2035, down to $45 per megawatt-hour, in the ballpark of solar, wind, and natural gas plants; a huge leap, but one that would more or less mirror the last couple of decades of solar power success.

Eavor’s CEO has said the company has a “clear line of sight” to sub-$60/MWh prices. Other companies, such as Fervo, have already started signing power purchase agreements; last November, it agreed to send 20 megawatts of geothermal power from Utah to a collection of nine communities in southern California. The goal is to start that power flowing by the middle of 2026.

Beard said she expects many or most of these startups to be acquired by bigger industry players in the coming years. And that will raise an uncomfortable question: Can climate activists swallow the bile that will come from watching the oil and gas industry win yet again?

“150 years of hostility”

“It’s gonna be Chevron, Shell, Exxon — if I list these names and say it’ll be these entities … the conversation is essentially over,” Beard said of her efforts to get people on board with what’s coming. “You bring in all of this frickin’ baggage. You know, you’ve got 150 years of hostility.”

With Big Oil coming off a record-setting year and apparently dialing back some of its “energy transition” rhetoric in favor of a return to its fossil fuel roots, there is always the chance that those companies’ involvement doesn’t end up central to the geothermal field. But if it’s Big Oil tech that’s driving it, it makes sense to anticipate Big Oil’s attempts to cash in.

Beyond just the knee-jerk reaction to seeing “Chevron” on your neighborhood geothermal plant, the physical resemblance to oil and gas drilling could cause some understandable not-in-my-backyard blowback. “With that development comes a drilling rig, oil and gas entities that show up to do the project,” Beard said. “With that comes friction and obstacles unless we can figure out very quickly — meaning within this decade — how to resolve that.”

Bryant called the involvement of oil and gas a “balancing act” for the industry. But the technology’s theoretical appeal to any corner of the political spectrum — baseload clean power and attendant emissions reductions, as well as an enormous jobs transfer opportunity — suggests it’s a manageable tightrope walk.

An exponential curve

Bring costs down by 90 percent, further develop the tools for high-temperature drilling, ease the public into a new era — all big asks when the world is on the clock. Experts say the big obstacle will be building those first few major power plants over the course of this decade, after which the dominoes should start to fall.

“I think we’re looking at five to seven years to really demonstrate that road map,” Moore told Grid.

Beyond that, the sky — or, the ground, in this case — is the limit. Beard thinks we could be at the start of an exponential curve, not so far away from truly rapid growth.

“Looking between 2030 and 2050 — what can we got to get done in that 20 years? Well, we can get another shale boom in that 20 years,” she said. “Let’s start cranking out 30,000 wells a year, 40,000 wells a year, 50,000 wells a year globally.”

The Texas geothermal report modeled out what such a world would look like: If the number could ramp up all the way to 70,000 wells per year between 2030 and 2050, geothermal could account for 77 percent of all the world’s electricity at the end of that period.

“Realistic?” Beard asked. “Hell yeah, let’s go.”