Geothermal planned for oil sands
“I think we’re going to get somewhere with this. It just comes down to how hot it is down there,” said MacConnachie, who began running the consortium in February along with colleagues from Shell Canada, Nexen Inc. and the Alberta Energy Research Institute.
A few other oil sands companies are “kicking the tires” of the consortium and may become full members, he said, adding that the group allows members to share any costs and risks associated with enhanced geothermal projects.
Under pressure to reduce their greenhouse gas emissions, oil sands operators have been looking for ways of extracting bitumen from the tar sands using less or ideally zero amounts of natural gas, the fossil fuel of choice and a major source of emissions in the region.
The oil sands are already the fastest-growing source of greenhouse gases in Canada, and current projects could lead to a four-fold jump in emissions over the next 10 years.
“We’re deadly serious about reducing our costs and reducing our environmental footprint,” said MacConnachie. “Geothermal is an option. But there are no home runs with these things. There are about six or seven things we’re looking at, each of which will reduce our CO2 footprint, but none of them will do it on their own.”
Enhanced geothermal works by pumping water into deep wells and exposing it to hot rock below. The water absorbs the heat and is pumped back to the surface. Heat is then extracted from the water to produce steam. MacConnachie said he expects to go “at least” four kilometres deep to tap the required temperatures in the hot granite. Nuclear power is another method of producing steam but he ruled out Suncor’s interest in that area, diplomatically adding that other companies “may have an application.”
There has been speculation that a subsidiary of Shell Canada is backing nuclear as a way to extract bitumen from limestone-trapped oil sands, but the company has never publicly confirmed its support.
Meanwhile, Energy Alberta Corp., a Calgary-based company that has partnered with Atomic Energy of Canada Ltd. to specifically promote the use of nuclear power in the oil sands, has turned its focus to building a nuclear reactor that would produce electricity for Albertans, according to Canadian Press.
The problem with nuclear, said MacConnachie, is that oil sands need heat more than electricity. Steam travels only 10 to 15 kilometres before losing its energy content. “Given the geography and distance between different oil sands companies, you have to say for (nuclear) to work, every oil sands company would need their own facility.” Geothermal, however, can be built where needed to produce steam for a specific application.
The consortium is targeting its first project at Suncor’s Firebag oil sands project, an in situ operation where horizontal wells are drilled and steam is injected under reserves. As steam heats the bitumen above, it drips to a lower horizontal well where it can be pumped out and sent to an upgrading facility.
“We need a lot of heat for our in situ operation,” said MacConnachie, adding that if geothermal works with one project it will work with others in the Fort McMurray area.
Suncor spokesperson Brad Bellows said it remains to be seen how much geothermal facilities can realistically contribute to operations.
“We take the approach that we’re here for a long time. In 2015, will we be happy that we have a geothermal well? Absolutely,” he said. “If it gets you part or most of the way to where you need to be, that’s still saving gigajoules of natural gas.”