CEO Interview: DEEP Earth Energy Boss Ready To Launch Canada’s First Large-Scale Geothermal Power Plant
Before focusing on the potential of geothermal energy, Kirsten Marcia spent many years as a geoscientist working in oil and gas, and in mining exploration for gold, diamonds and coal.
The knowledge gained, especially in horizontal drilling techniques, translated well for geothermal and made sense when considering a career move, says Marcia, who founded DEEP Earth Energy Production Corp. in Saskatchewan in 2010.
“I was a wellsite geologist fresh out of university, and we drilled dozens of wells horizontally in the Weyburn and Estevan area,” recalled Marcia, who is also president and CEO of the Saskatoon-based company.
“The segue here is that a colleague approached me about this geothermal resource, and whether we wanted to explore it to see if it had the legs to be an economic project. It came at such a unique time in my career, where I had some experience, I had some tools in my toolbox, and I could take that leap.
“We raised initially a million dollars in the classic friends and family way, from people that knew a little bit about my background and my tenacity.”
Marcia says the project did not initially move ahead as quickly as desired due to a lack of finance, but by 2019 it had received $25.6 million in federal funding.
Using oil & gas knowledge to tap geothermal
Now she is overseeing phase one of Canada’s first large-scale geothermal power plant, southwest of Estevan near the U.S. border. The 25MW plant is also the first in the world to borrow from the oil and gas industry’s horizontal drilling practices to tap into geothermal liquids underground.
“It's all this innovation on the backs of the oil and gas industry, who've been dealing with these challenges for decades, but for the first time now applied in a geothermal project,” Marcia said.
“The same rules apply for geothermal.”
The DEEP plant will initially provide 5MW in phase one for SaskPower, with a further 20MW for the utility planned for phase two, pending approval, enough power in all for 25,000 households.
For phase one, DEEP is using Weyburn-based drilling company Panther Drilling and Calgary-based Horizon Drilling Inc.
Production and injection wells will be drilled to a depth of approximately 3.5 kilometres, and horizontally for an additional three kilometres. DEEP will have a “ribcage” layout and geothermal well field, with wells of equivalent depth, lateral length, and step-out similar to those seen in the Western Canadian Sedimentary Basin.
Also incorporated will be the results of five vertical and one horizontal test wells already drilled on-site between 2018 and 2021. All wells will be completed with carbon steel tubing covered in a non-metallic coating, to prevent corrosion.
Phase One ‘rib cage design’ to be built in Q3 2023
It was announced in February that field construction for the first phase will begin in Q3 2023, with the plant becoming operational next year. Marcia says the second phase will follow once a second contract with SaskPower is signed.
“We can say that that is now in its draft form, that's going back and forth between SaskPower and DEEP. That is in progress and should happen quickly,” Marcia said.
Marcia says the first 25MW field will use only 10 per cent of DEEP’s entire subsurface lease of 39,568 hectares. The full subsurface lease is anticipated to support an eventual geothermal buildout of multiple power facilities supplying greater than 200MW.
“This first five megawatts is just the beginning of the rib cage,” she said.
“[But] we're not just focused on a cute little demonstration project. We're doing this because it has commercial viability.”
Phase one will also allow DEEP to ensure potential problems are uncovered and dealt with prior to wider expansion.
“What we're doing with this first 5MW is, in full transparency, to make sure that we capture any additional extensive learnings on a small scale versus a larger scale,” Marcia said.
Another unique aspect for the project is that the rib cage design keeps the activity within a relatively tight space, allowing easier access.
"We have alternating well pairs that run laterally in one direction, call it east-west,” said Marcia.
“Being able to expand that ribcage design with more wells allows for really wonderful scalability. The more wells we drill along that ribcage along the spine of the project, the more geothermal output will help.”
Why Saskatchewan works for geothermal
Without the same level of volcanic resources found in the U.S., Marcia describes the geothermal conditions at the DEEP site as “the lowest hanging fruit in Canada from a geographic standpoint,” along with the ease of ability to join the SaskPower grid.
"For us, you know, we're only 120 C. That's very hot, 120 [degrees], but for geothermal, that's approaching the lower end,” she said.
“We were struggling when we were drilling our vertical wells to be able to produce the fluids at economic rates.”
It was a long road of test-and-see to get the point of starting phase one, she adds.
“It's been tricky, you know. In the past few years, we joked that the project has been like a game of whack-a-mole, where you think you got everything solved and then — boom —– something else pops up,” she laughs.
“The biggest challenge has been fluid production. In these lower temperature geothermal resources, we have to move a lot more fluid than if we were at a higher temperature.
"And then the second biggest challenge was how corrosive our geothermal brine is. It's ten times saltier than seawater. We thought we would be able to use corrosion inhibitor chemicals, but the feed rate was just far too high. We are now using [the] special coated tubing to solve the problem. That's all very unique.”
World-class potential for low temperature geothermal
And Marcia says the DEEP project is just the first stage of a low temperature geothermal industry that could be established around the world, thanks to that early connection to oil and gas technology.
“It's interesting. There's been a hesitation in the geothermal sector, in my opinion, to embrace oil and gas technology to develop renewable resources,” she says.
“But it's so funny because the way you produce a geothermal well, especially in these lower temperature resources, is exactly like an oil well. They're exactly the same. Just that we're not producing any oil. We're just producing … hot fluids.”
The company is also looking to customers beyond SaskPower for future phases, but she was not able to elaborate more at this point.
What is making geothermal energy additionally attractive compared with other types of renewable energy, she says, is the fact that unlike wind or solar, geothermal never switches off.
Marcia also hopes the site could be used for carbon sequestration.
“It creates a whole other potential add-on industry for us and [a possible] add-on to our geothermal project that we're not doing necessarily on this first project. But that's something that we're looking very carefully at,” she said.
Throughout the whole journey, what Marcia says she has most enjoyed is working with her team and building DEEP together.
“We have a really high functioning group of collaborators. I think people feel safe to challenge our concepts or ideas,” she said.
“Our organizational structure is as flat as a pancake. We all work together in a very lateral way, as opposed to a very top-down way. It's a cohesive team effort that I think keeps people excited.”
- New Energy