Canadian Natural Resources Limited says a test of downhole electrical heating at its Peace River oilsands acreage has validated the theory of the technology and proven its economics.

The single-well experimental scheme at Cliffdale started operating in April 2017, around the same time that Canadian Natural acquired the Peace River properties, and the majority interest in the Athabasca Oil Sands Project, from Shell Canada.

The premise behind project was that in situ wellbore heating would reduce oil viscosity and reduce the pressure differential inside the horizontal section of the wellbore, resulting in higher production and increased reserves, according to a performance update made public by the Alberta Energy Regulator this week.

Canadian Natural said that production increased to 37 bbls/d from 25 bbls/d following startup of the downhole heater, and that during periods of heater downtime, oil production decreased by this same volume.

“Increased oil production observed during operation of the downhole electric heater provided evidence that the downhole electric heater experimental trial was successful in validating [the] original theory,” the company said. “Increased oil rates have proven economics of continuing the operation of the downhole electric heater and CNRL will be applying to continue the enhanced oil recovery process.”

Earlier this month, Suncor Energy Inc. received regulatory approval to test downhole electrical heating in a single well at its MacKay River SAGD project. The company intends to use the system to pre-heat the reservoir prior to steam injection and confirm potential to reduce pad-level steam usage, accelerate production ramp-up and improve peak oil rates.

The company noted that electrical heaters have been piloted in Canadian reservoirs since 2004 including by Royal Dutch Shell plc at its Viking project in December 2004 and at its Grosmont carbonate project in 2012; by Athabasca Oil Corporation at its Leduc carbonate property in 2012; and by Perpetual Energy Inc. at its Panny LEAD pilot in October 2015.