Diavik will build large solar plant to power it through closure

Rio Tinto will build a solar plant at its Diavik diamond mine to help power the work needed to close down the facility.

Diavik, a big slice of the NWT’s economy since it opened in 2003, now expects to end production in 2026.

On Thursday, Rio Tinto said more than 6,600 solar panels will be installed at Diavik. Work will begin in the coming weeks and the company hopes the solar plant will be fully operational in the first half of 2024.

According to Rio Tinto, the plant will provide up to 4.200 MWh of electricity. The project is funded through two government initiatives.

“The solar power plant will provide up to 25 percent of Diavik’s electricity during closure work that will run until 2029,” the company stated in a press release.

“The facility will be equipped with bi-facial panels which will not only generate energy from direct sunlight, but also from the light that reflects off the snow that covers Diavik for most of the year,” Thursday’s press release continued.

“It will cut diesel consumption at the site by approximately one million litres per year and reduce emissions by 2,900 tonnes of CO2 equivalent, which is comparable to eliminating the emissions of 630 cars.”

Diavik president Angela Bigg said the solar panel was decided upon after the mine could not find a vendor to supply a large-enough battery that would work in the cold.

Diavik already has the largest wind turbine facility in the North, a system of four 2.3-megawatt turbines that the mine has previously said saves around $5 million a year in power costs.

Earlier this year, Diavik staff said those turbines are expected to stay at the mine until the end of their useful lives.

Diavik’s solar plant is paid for in part by the NWT’s carbon tax. The system devised by the territory involves placing 12 percent of carbon tax payments from diamond mines in a fund that can then be spent by the same mines on renewable projects.

This is the first time that fund has been used by anyone.

Diavik said it was using $3.3 million from that fund to help build the plant, plus $600,000 from a separate federal clean-energy tax credit.

“This collaboration exemplifies our commitment to facilitating sustainable development while reducing greenhouse gas emissions in the Northwest Territories, and should be a signal of how our economic development can continue to position us as leaders in these spaces,” stated NWT finance minister Caroline Wawzonek.

The overall cost of the project was not given in a Thursday press release. By phone, Bigg said the expected cost is around $4 million – in other words, roughly the total of the two government contributions.

“I wouldn’t say that it’s fully government-funded,” Bigg told Cabin Radio. “The carbon tax that Diavik has paid to date far exceeds the amount of funding we’ve been able to utilize from this fund for the solar farm.”

She added: “It’s not really about a significant cash saving, it’s more about how we can look at reducing our emissions. The project itself sort-of is net-zero impact to the mine. We’re not making a lot of money and we’re not losing a lot of money, in terms of the project itself. However, having the reduction in emissions is really what we were chasing here.”

The fate of the solar plant after 2029 is unclear.

“Diavik is working with the Government of the Northwest Territories and community partners to determine how its renewable energy infrastructure can best benefit the region following closure,” Rio Tinto stated, referring to both the solar panels and the wind turbines.

Bigg said the solar panels have an estimated life of 25 to 30 years and will be installed in wire baskets designed to make them easy to install and to remove later, if they are needed elsewhere.

“We are looking at potential options to redeploy or reuse all of our assets, and the solar farm is absolutely part of that scope,” she said.