A Calgary company says a giant underground radiator is the easiest way to describe its unique technology to harness the Earth’s natural heat for warmth and power.
Eavor Technologies Inc. is developing a prototype for a closed-loop geothermal system that circulates liquids through kilometres of underground well bores, picking up heat before returning to the surface.
The heated liquid can be used for heating or to create power using heat-to-energy technology.
Eavor president and CEO John Redfern describes the technology as akin to creating a giant subsurface radiator.
The $10-million demonstration project will be ready for testing by this fall on a site between Rocky Mountain House and Sylvan Lake. The company is not revealing the exact location.
Besides showcasing the potential of its geothermal technology, known as Eavor-Loop, the facility is expected to be used as a research and development test bed.
Precision Drilling, Shell New Energies and Natural Resources Canada, which announced $6.7 million in funding last month, are among the partners working with Eavor.
Geothermal technology is not new. However, traditional large-scale projects have usually been limited to areas with uncommonly hot underground conditions.
“Alberta, in general, wasn’t a traditional geothermal hotbed, simply because we don’t have the geological heat here that traditional geothermal needs,” Redfern said.
Prime geothermal locations “tend to be on the Pacific Ring of Fire or Iceland, or places like that with active volcanoes.
“That is not us. So we had to come up with a different technology that could cost-effectively operate in moderately warm sedimentary basins like we have here.
“We have vastly expanded the geography where geothermal could work.”
Eavor’s closed-loop system involves drilling a pair of vertical wells 2.4 kilometres deep at the demonstration site. Horizontal well bores will connect the two vertical shafts.
The loop is closed above ground, with a 2.5-kilometre pipeline creating a closed system that circulates a benign fluid using a natural “thermosiphon effect” that causes warmer liquids to rise as colder, denser liquids are introduced.
“Once you get the motion going, it pumps itself,” he said. That eliminates the cost of running pumps, greatly reducing operating costs.
Redfern said the use of liquids designed for better heat retention than the typical brine found underground, and the closed-loop system, allow geothermal to work efficiently and cost-effectively in Alberta’s less-than-ideal conditions.
And unlike other systems, which pump heated underground brine out of aquifers to the surface before pumping cooled brine back down, Eavor’s system does not take anything out of the ground to produce heat or convert to energy.
Redfern said the technology can be used for just about any application. For instance, an Eavor-Loop would be a natural fit at a greenhouse business, or breweries, where large amounts of heat are required.
Since heat cannot be moved long distances efficiently, the Eavor-Loop system would be located near its user if heat is the requirement, said Paul Cairns, Eavor chief business development officer.
If used to generate electricity, which is easily transmitted, there is more flexibility on where the system can be placed and a broader potential market, said Cairns.
The company already has customers interested in the technology in Brazeau County. Other potential international customers are watching the results of the demonstration site closely.
In Alberta, where the oil and gas industry is weathering an extended slump, Eavor’s technology could provide jobs if it takes off. Just about all of the equipment used in the oilpatch can be used to build Eavor-Loops.
“This could be the spark to a tremendous amount of activity,” said Redfern.