The former Con Mine's headframe stands out in Yellowknife's skyline. Underground heat from the defunct gold mine could heat 39 downtown buildings as part of a proposed energy plan. (CBC)

Geothermal heat from a former Yellowknife gold mine could soon be heating dozens of buildings in the downtown, if city council goes ahead with a $60-million renewable energy plan that's in the works.

The city's proposed project, if implemented, would have 39 downtown buildings drawing underground heat from the defunct Con Mine, in combination with a wood-pellet boiler system.

Both methods, according to city officials, could significantly reduce the city's use of fossil fuels and reduce its greenhouse gas emissions.

A Vancouver-based resource management firm reported to Yellowknife city council on the project's financial viability on Monday, detailing possible risks, issues and timelines.

Council will vote next month on whether to move ahead with the geothermal plan. The city is meanwhile looking for companies that would invest in the project.

'It can be done': mayor

"We've proved that technically it can be done. Our business plan shows that financially, it's a good idea," Yellowknife Mayor Gordon Van Tighem told CBC News.

"So now we're at the next stage, where we will go out and find out what the real prices are from the people that supply such things," he added.

The Con Mine, located about one kilometre outside the city's downtown, produced more than five million ounces of gold from 1938 until it closed in 2003.

Yellowknifers have long thought about drawing geothermal heat from the abandoned mine, as former miners have reported temperatures exceeding 30 C when they were underground.

If the project goes ahead, a network of distribution pipes would have to be built to deliver heat from the mine to various downtown buildings.

Oil would still be used under the proposed geothermal plan, but would make up five per cent of the energy used. Still, Yellowknife could save 7.6 million litres of oil and lower greenhouse gas emissions by 17,000 tonnes a year under the proposed plan.

The buildings that tap into the geothermal system could reduce their greenhouse gas emissions by 85 to 95 per cent, according to the city.

Letters of support

"I'm cautiously excited because we still have a number of steps to go through. It has to be financially viable," Van Tighem said.

The viability study presented at Monday's council meeting warned the city to be prepared in case no one comes forward as geothermal heat customers.

Some of Yellowknife's major property owners — including NPR Commercial Property, Bellanca Developments Ltd., and Polar Developments Ltd. — have submitted letters to council expressing some support for a geothermal heating system.

But should Yellowknife need to scrap its plans for a geothermal heating system before it gets up and running, no major financial loss would be felt, as the city could sell what it has developed as intellectual property, according to the viability study.

"We want to make sure that there's milestones in there that allow us to say, 'No, this isn't working, this is not going to achieve the benefits that we want,'" Coun. Bob Brooks said at Monday's meeting.