Rebecca Pearce is a geophysicist and science lead of the ultradeep geothermal project at the Cascade Institute at Royal Roads University. Ian Graham is a physicist and resident fellow at the Institute.
Carbon emissions from burning coal, oil and natural gas are propelling a stunning rise in global temperature: The four months through September were 0.44 C warmer than the same months just eight years ago, at the start of the last major El Niño cycle. In 2024, we’re likely to cross the critical 1.5 C ceiling – a level of warming that scientists say will entail catastrophic consequences – and stay close to or above that threshold thereafter.
The global transition from fossil fuels to zero-carbon energy will require a massive increase in electricity production from renewable sources. Wind and solar power will be essential contributors. Yet weather-related blackouts, challenges in financing offshore wind in Europe, and Alberta’s moratorium on new renewable projects show that relying largely on wind and solar is risky. The world needs additional sources of green electricity to meet skyrocketing demand.
This is why a worldwide race for next-generation geothermal technology has begun – and why Canada needs to get serious about joining, lest it fall to the back of the alternative-energy pack.
Geothermal power taps thermal energy radiating from the Earth’s interior to the surface, conducted through subsurface rocks and fluids. We can access this heat by drilling into hot rock and channelling heat-bearing water back to the surface through a production well to generate electricity. Today, we can do this only where natural reservoirs of hot water lie close to the surface – generally less than five kilometres deep – but the true prize lies eight to 15 kilometres down in hard rock with supercritical temperatures, where there’s enough energy to potentially meet the world’s future electrical needs thousands of times over.
Deep geothermal plants would generate non-intermittent baseload power with minimal greenhouse emissions, and they’d be highly resilient to the effects of climate change, unlike wind, solar and hydro facilities. They could be built nearly anywhere, including close to or even within cities. And because they’d have a high power density – producing thousands of watts per square metre of land occupied – they’d cause far less ecological damage than wind, solar or hydro.
Around the world, governments and energy companies are starting to see these advantages. State-supported R&D projects are under way in the United States (Utah FORGE), Japan (the Beyond-Brittle Project) and Iceland (the Deep Drilling Project). Until recently, the Canadian government’s support for geothermal projects has consisted mainly of investment tax credits and research within government laboratories, but in October, Canada took a big step forward with the announcement of a $90-million investment in Alberta-based Eavor Technologies Inc. by the federal government’s Canada Growth Fund.
Yet Eavor’s proprietary closed-loop process is only one of several emerging geothermal technologies in which Canada should be a global leader. And were it not for the few pioneering Canadian projects such as DEEP Corp., Tu Deh-Kah, Swan Hills Project, Alberta No. 1, and Kitselas Geothermal Inc., all of which are tapping relatively shallow heat, hardly any of our own geothermal resources would be under development.
Canada can do far better. Workers in our fossil-fuel and mining industries already have a wealth of expertise in drilling and subsurface resource extraction, and in Western Canada, we have a ready-made labour force that can be employed in this new industry almost immediately, with little or no retraining required. We also have a huge variety of geological settings, with regions of good geothermal gradients in hard, granitic rock with nearby populations that would benefit directly from renewable heat and electricity plants.
But to get to the front of the deep geothermal pack, Canada needs to do two things, now.
First, we need to set up one or more test sites focused on hard-rock drilling to depths with supercritical temperatures. These sites would allow industry to collaborate with scientists from Canada’s national laboratories and universities to experiment with new drilling technologies. The initial aim would be to drill quickly – and thus economically – into hard rock that’s hot enough to produce electricity at a reasonable return on investment, at locations where such heat is relatively close to the surface. Candidate locations include the southern Northwest Territories, northwestern Alberta, and British Columbia’s coastal range. As drilling methods improve, we’ll drill deeper into even hotter temperatures, until we’ve developed the ability to harness deep geothermal power anywhere on the planet.
Four novel drilling methods that offer the possibility of reaching great depths – percussive, plasma, microwave and water-jet – are generating lots of excitement, not to mention investment into research and development. But modified conventional drilling techniques have so far been the most successful. The FORGE project, which is funded by the U.S. Department of Energy, has used optimized rotary drilling to achieve a penetration rate of 60 metres an hour – roughly 10 times faster than is typical in hard rock at the depth FORGE is drilling. Canada already boasts some of the world’s best conventional drilling operators and laboratories, so we can get to this technological frontier quickly and then help advance it.
Second, we need to develop clear national and provincial regulatory frameworks that enable easier review, approval and monitoring of geothermal projects. Outside of British Columbia and Alberta, such projects fall into ill-fitting regulatory frameworks governing exploitation of groundwater or oil and gas. This ambiguity discourages investment by venture capitalists and power companies.
These two steps would de-risk emerging technologies, attract investment and ultimately make Canada a leader in harnessing deep geothermal energy – a technology we could then sell around the world.
At the Cascade Institute, we estimate that setting up and operating a Canadian test site would cost around $200-million, with most of the initial investment necessarily coming from federal and provincial governments. That might seem like an impossibly steep sum. But it’s less than one-hundredth of the $30-billion the federal government is spending on the Trans Mountain pipeline. And geothermal is an investment in the future, not the fading past.
The world’s deep geothermal future can bear a maple leaf, but only if Canada aggressively supports a bold and diverse program of geothermal research and development – and soon.