Canada urged to “go deep” on geothermal energy

NOTE: This is part two of a two-part Research Money series on developing Canada’s geothermal energy resource. Part two examines the potential for “deep enhanced geothermal” (five kilometres or more deep). Part one, published on Aug. 17, focuses on “shallow” (less than five km deep) projects, including government and private sector investment and innovation.

Canada has enough energy underground to supply clean electricity and heat for the entire country many times over. But this “ultra-deep” geothermal energy source is being ignored, proponents say.

Although the federal government and the private sector are ramping up funding for relatively shallow (less than five kilometres deep) geothermal projects, there is no support for developing ultra-deep enhanced geothermal systems.

“This opportunity hasn’t received the attention it deserves,” says Dr. Thomas Homer-Dixon, PhD, founder and director of the Cascade Institute, a research centre based at Royal Roads University in B.C.

“If you can drill sufficiently deep enough underground — say 12 kilometres — there is enough thermal energy in the Earth to satisfy the entire planet’s energy needs literally hundreds of times over,” he said.

Earlier this year, the Cascade Institute released a report calling on the federal and provincial governments and the private sector to create a world-leading Canadian capacity to design, build and operate deep enhanced geothermal systems (EGS) in Canada and internationally.

“Canada should make a large industrial and R&D bet on EGS, to help achieve Canada’s net-zero electricity targets and provide worldwide engineering opportunities for Canadian businesses,” Dr. Ian Graham, PhD, senior fellow at the Cascade Institute, said in an interview.

The biggest challenge, he added, is that it is still too expensive to drill deep enough to make ultra-deep geothermal projects economically viable. According to the Cascade Institute’s report, it would cost about $50 to $100 million to drill a 10-km-deep geothermal well with currently available drilling technology.

Graham argued that cost needs to be reduced ten-fold, to $5 million to $10 million per well, to make an ESG system viable economically. “We believe this is doable, because this is really just a drilling technology problem.”

Solving that problem would open up 99 percent of Earth’s subsurface to ultra-deep geothermal projects, compared with less than one percent available for the shallower projects now underway, he said.

In Canada, the shallow projects being developed in B.C., Alberta and Saskatchewan are in comparatively softer sedimentary rock, where the geothermal heat is close enough to the surface to be accessed with drilling technology used by the oil and gas industry.

However, ultra-deep geothermal requires drilling through much harder granite and metamorphic rock – the geology that comprises the Canadian Shield underlying central and eastern Canada. That makes the drilling cost prohibitively expensive, using conventional drilling bits and associated drilling technology.

“We need a lot more innovation in this area to be able to do much more aggressive geothermal rollouts,” Graham said.

Deep geothermal has advantages compared with other renewables

Companies in other countries are engaged in just that kind of innovation, he said, pointing to new technologies for hard rock drilling. These include:

• Strada Global in the U.K. is working on “percussive drilling,” which hammers the hard rock, fracturing it into extractable pieces.
• GA Drilling in Slovakia is developing technology that uses rapid pulses of high-temperature plasma to vaporize and fracture the rock face.
• Quaise Energy in the United States, which has raised US$63 million to date, is pioneering technology that uses gigahertz microwave to weaken the rock, making it easier for drill bits to cut through it.

“The real challenge is taking the technologies that are under development and bringing those to the point where we can actually do this practically and commercially,” Graham said.

Once that challenge is overcome, ultra-deep geothermal offers several advantages over other renewable energy sources such as solar, wind and hydropower, Homer-Dixon noted.

Those sources each generate a relatively small amount of power per square metre on the large land surface they occupy, he said.

But deep enhanced geothermal systems could potentially deliver power densities that are orders of magnitude higher than other renewables, Homer-Dixon said.

Occupying a comparatively small surface area and with most of its infrastructure underground, an EGS power plant is also less vulnerable to extreme weather events resulting from climate change, he said.

Large hail can destroy solar photovoltaic panels, wind turbines can be damaged by hurricane-force winds and ice storms, and hydroelectric dams’ power curtailed by shrinking reservoirs due to prolonged drought. And regardless of the climate, a new generation of small modular nuclear reactors will still produce radioactive waste that calls for long-term management.

In contrast, ultra-deep geothermal “gives you a really good long-term solution and reduces the risk of something happening to other net-zero technologies,” Homer-Dixon said.

Graham said a potential risk with shallow geothermal projects is triggering small localized earthquakes, by injecting water into rocks near fault lines and that are already under stress. This has occurred with hydraulic fracturing operations to unlock oil and gas from geologically “tight” formations.

However, deep EGS projects, which also use hydraulic fracturing and injected fluid, need not be located in seismically active areas. And even if seismic activity triggered at these greater depths, Graham suggested the effects will likely be smaller and less obvious on the surface, Graham said.

Plumbing the political depths

While the drilling technology problem may be solvable, ultra-deep geothermal — and geothermal development in general — also faces political challenges.

Graham noted the need for federal and provincial governments, which oversee regulatory bodies such as Natural Resources Canada and the Geological Survey of Canada, to adopt an operating model that gives geothermal developers an easy road into applying and getting approval for projects. Even more helpful would be a government-sponsored, real-world operating laboratory where companies could test their innovative drilling technologies in a regulatory risk-free environment.

Another obstacle is the unwillingness of provincial power authorities to buy independently produced power, since any new source will cut into cash flow these organizes require to cover capital costs of their existing facilities, like BC Hydro’s massive Site C dam. In 2019, the utility declared a surplus supply of electricity as the reason for indefinitely suspending its 11-year-old Standing Offer Program, which had provided independent power producers an opportunity to develop small-scale renewable energy projects.

Hydro Québec has been similarly unreceptive to deep enhanced geothermal systems. In a report on the subject last year, it concluded: “EGS projects remain marginal, because while the system may at first glance appear simple, it is in fact quite complex to develop and very expensive.”

As for federal investment, André Bernier, director general of Natural Resources Canada's Electricity Resources Branch, said this support is devoted to shallow geothermal projects that can be done with existing drilling technology and expertise.

“From an NRCan perspective, I think there’s a real recognition of the technical potential of going even deeper,” he said. “But in focusing on shallow geothermal, there’s been a very deliberate focus on an area where the challenges are lower and the potential is probably more immediate.”

Homer-Dixon and Graham, however, point to other countries that are supporting R&D in ultra-deep geothermal.

On August 15, the U.S. Department of Energy’s (DOE) Frontier Observatory for Research in Geothermal Energy (FORGE) field laboratory announced up to US$44 million for projects to develop and test technology to foster innovation in deep enhanced geothermal systems. FORGE is DOE’s dedicated field lab – in addition to a Geothermal Technologies Office – for developing technologies to create, sustain and monitor EGS reservoirs.

In the U.K., the United Downs Deep Geothermal Project has drilled a well nearly 5.3 kilometres deep into hot granite rocks, with the power plant scheduled for operation by mid-2023.

Meanwhile, Canada, which has developed national strategies for small modular nuclear reactors and hydrogen production, nothing of the sort exists for geothermal. The Cascade Institute's report calls for a Canadian program that would massively scale-up EGS geothermal production and R&D efforts over the next 15 years, which would include government and industry support to create functional, economically viable EGS reservoirs at depths of up to 10 kilometres.

The report also emphasizes that Canada should retain the intellectual property from these efforts, through crown corporations or public stakes in privately held corporations, so that any resulting inventions continue as Canadian assets.

The Cascade Institute now plans to identify the most effective governance and incentive structure for building a deep enhanced geothermal innovation ecosystem, and map an R&D pathway for EGS drilling.

Says Homer-Dixon: “We’re looking at a timeline of somewhere in the next 15 years or two decades to bring this ESG technology to scale, where it’s generating a substantial contribution to the [electricity] grid.”

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