Estevan – After nearly a decade working to develop the concept of geothermal power, Saskatchewan's Deep Earth Energy Production (DEEP) Corp finally drilled the first hole in southern Torquay, in the view of the American border. A successful project will establish the first geothermal power facility in Canada.
On November 8, the company, led by CEO Kirsten Marcia, drilled a conductor pipe and rathole, in anticipation of full drilling the following week. On November 13, the drilling rig was moved, and the well was boiled on November 14.
The hole will be a significant hole, aiming to be the deepest in Saskatchewan. This will exceed two Aquistore wells as far as 100 meters, to a total vertical depth of around 3,500 meters.
Marcia spoke with Pipeline News on November 9.
MENDALAM was formed in 2010. It has the "extraordinary surprise" he noted, where they will move very far, then slow down by funding. But in the past few weeks, they received $ 4 million in new equity funding that allowed the company to start drilling. They have rented drilling rigs that have worked nearby, but will have a window of opportunity.
This well is estimated to take 25 days to drill, longer than ordinary wells in the area. That's partly because they plan to cut 200 meters of the core at the bottom, including cutting the core into the PreCambrian basement, which underlies the sedimentary bed.
"Hopefully we will catch some core in the basement," he said. They aim to go up to 20 meters to the basement, because that will provide the depth needed for the logging tool that follows to scan the entire sediment column.
While Marcia, herself, is a geologist who used to sit in a well, DEEP has hired John Lake, a prominent Saskatchewan geologist who once graced the cover of the Pipeline News, to sit well.
This hole became the first of six, paving the way for three production wells and two injection wells. Wells must be placed 300 to 500 meters apart.
This initial well will be smaller in diameter, at 7 inches, right down. The next production well will be 9-5 / 8 inches.
That is to handle a large enough electric submersible pump (ESP) that will move a large amount of water, pulling it from the formation of Winnipeg and Deadwood which forms the last 200 meters of the hole. The Icebox Formation, overlaying the Winnipeg formation, acts as a caprock, as in the Aquistore project, about 29 kilometers east.
Aquistore injects carbon dioxide from the Boundary Dam Unit 3 Carbon Capture and Storage Project into a deep saline aquifer, 3,400 meters and two kilometers west of the power plant. SaskPower, which has donated $ 1 million for the DEEP project, shared data with DEEP obtained from Aquistore.
Marcia noted that in this case, the Icebox acts as a heat insulation for their purpose.
This well is the initial test of resources, which is needed to correct the assumptions, he explained.
Marcia said the well was "about a mile" from the same deep well drilled by Canadian Natural Resources Limited in the 1980s. The well was loaded with a temperature of 95 C, but three days later, it registered 126 C.
And that's why this area is very interesting, and why they drill so deeply. Marcia noted that this was not a volcanic geothermal project, but one in a sedimentary basin. "The deeper you go, the warmer it is," he said, because heat comes from the center of the earth.
"This is hot mining. Heat is a resource. Water is a medium for transferring resources. "
The plan was to drill this first well, and then finish it three weeks later to find the actual temperature. They will drain the well for seven days, using it to model full production wells. They will also test the injectivity of the Mannville formation for future injection wells.
At the end of March, testing is expected to be fully reviewed. "If the first well provides enough data to convince lenders for production wells, we do it," Marcia said.
Then after the spring break of 2019, the plan was to continue with production and injection wells, drilling them as "doublets."
Injection wells, however, will not reach the same depth as production wells, but rather more shallow Mannville formations, which are usually used for dumping wells in the area. It is possible that this initial well can be used as an injection well too. That may be needed for maintenance of pressure in the reservoir.
Each production well will use ESP which attracts one megawatt, approximately 1,340 horsepower, power. The total power generated by this project is expected to be 10 megawatts, but after power usage from the pump and installation facilities is considered, net electricity production will be five megawatts. This will be tied to a substation at Bromhead.
The long term part of the project is the electricity production facility itself.
An above-ground installation uses the organic Rankine cycle. By using a low boiling working fluid, hot water taken from the production well moves its heat through a heat exchanger, causing the working fluid to turn into gas (ie boiling) and driving the turbine. The cooling tower cools the working fluid back to the liquid phase for reuse. The water is then pumped under the injection well.
This system is almost identical in concept and on the scale of what has been done at the compressor station at Alliance Pipeline, which runs through Saskatchewan. Those heat recovery power plants were installed in Kerrobert, Loreburn, Estlin and Alameda in 2008, and each produced five megawatts of clean electricity.
Indeed, the fact that the DEEP geothermal concept uses established and existing technology – production drilling and injection wells, uses heat to operate the Rankine organic cycle power plant – has made it somewhat problematic in attracting funding, according to Marcia. There is nothing new, per se. But that is a new application of this technology in sedimentary basins, and in particular, the Williston Basin, which makes it unique
This project can be duplicated in size, he said, but at a certain point, it can make more sense to replicate the project as opposed to adding to it. It can be scaled and can be repeated.
The system will cool water from 120 C to around 65 C, but that still means there is a lot of heat that can be used in it. While the goal is to produce electricity, not cucumbers, he feels it is possible on the road to using waste heat for greenhouses or other applications.
All said, if everything went well, in two and a half years, Marcia said they could have power to the electricity network, renewable, basic load power runs around 95 percent of the time. He called it "The most interesting of all renewable energy," and said that it could offset coal.
Marcia noted that they use oilfield data, technology and processes to build renewable and non-industrial resources, no one knows that geothermal resources are here.