Heavy power usage at the Bellekeno silver mine has forced the Yukon Energy Corporation to burn hundreds of thousands of litres of diesel to feed the Yukon’s northern grid.
Yukon Energy will burn four times as much diesel this year on the Dawson City-Mayo electrical grid than it usually does, because of the mine.
“We’ve been running diesel anyway over the last two years,” said Janet Patterson, the corporation’s spokesperson. “But we’re burning more diesel than we have had to in the past.”
A lot more.
The northern grid is usually supplied by hydroelectric power from the Mayo dam – currently undergoing an expansion.
In 2008, Yukon Energy burned 119,000 of diesel to generate power the dam couldn’t provide.
Last year, they burned 138,500 litres.
Those numbers are puny compared to the diesel Yukon Energy expects to burn by the end of December – around 550,000 litres.
That’s 11 B-trains (double 18-wheelers) filled with diesel.
The cost puts a major strain on the utility’s books.
It costs around 10 cents a megawatt to make power from hydro and 30 cents a megawatt to make it from diesel.
Yukon Energy knew it was going to be an expensive year because of Bellekeno.
They prepared for the extra demand and adjusted rates accordingly, said Patterson.
People won’t see any rate jumps – the diesel cost is already worked into the utility’s finances, she said.
Yukon Energy and Alexco, the mine’s owner, signed a power purchase agreement in September.
The price the mine pays for power is approximately 10.5 cents per kilowatt hour, says a Yukon Energy news release from that month.
It fluctuates depending on how stressed the grid is when the mine needs extra power.
There’s a fixed charge of almost $7,300 per month and then an additional peak charge for when power demand is high.
Yukon Energy was not able to answer whether it loses money or makes a profit from Bellekeno when the high diesel costs are considered.
The utility does not break things down that way, said Patterson.
A more detailed breakdown of the mine’s cost could not be determined before press time.
Until the Yukon’s two grids are connected, Bellekeno will put a heavy burden on the Mayo-Dawson line.
The total demand on the grid is around 6.5 megawatts, with Bellekeno sucking about 1.5 megawatts of that.
Mayo B can only produce around five megawatts, leaving Dawson City’s five diesel generators to pick up the rest.
Worse, early ice formation on the Mayo River has curbed the dam’s power production.
Instead of five megawatts, it can only provide four.
“That is adding to the need for diesel,” said Patterson.
The heavier reliance on diesel will remain until the grid is connected with the Yukon’s southern grid, which has two major hydro dams on it.
The Pelly Crossing connection is expected to happen in April or May, said Patterson.
After that, the Mayo dam expansion – known as Mayo B – will add another five to 10 megawatts to the united grid.
At the moment, only two of Dawson City’s diesel generators are fired up.
Those diesels are feeding power to Dawson while the Mayo dam is servicing Bellekeno, said Patterson.
It helps reduce the amount of energy loss on the transmission line.
Yukon Energy is also using diesel on the southern grid due to the recent cold snap.
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