Domino effect trips Aishihik and Whitehorse generators

‘Catastrophic” is not likely the word most people would have used to describe yesterday afternoon.

‘Catastrophic” is not likely the word most people would have used to describe yesterday afternoon.

But trouble was brewing at the Aishihik Hydro Plant, which feeds into the Whitehorse-Aishihik-Faro transmission line.

At 1:30 p.m., one of the two generators running at the Aishihik dam failed, causing a “catastrophic outage,” according to Yukon Energy spokesperson Janet Patterson.

It plunged most of Southeast Yukon into darkness.

“One of the Aishihik generators went down and we don’t know why,” added Patterson.

“We’ve got crews out there desperately trying to figure out why.”

Like dominos, generators then began to fail all the way down the grid.

The other generator at the Aishihik facility was unable to produce the required energy on its own, so it shut itself down.

“What happens is the other generators say, ‘Oh, my gosh we’re being asked to provide all this electricity, we can’t provide this much electricity now, we’re going to go away,’” Patterson said Monday.

With the Aishihik station at a standstill, the Whitehorse generators were left to produce all of the electricity.

They could not feed demand.

So, the two Whitehorse generators stopped churning out energy as well.

“It’s a way of protecting themselves because if (the generators) didn’t they would basically blow up, they would destroy themselves,” explained Patterson.

“It was like boom, boom, boom, and we ended up with no hydro generators.”

This meant that residents from Teslin, to Whitehorse, to Haines Junction, to Carmacks and Faro were powerless for up to 12 hours.

While crews were dispatched immediately Sunday afternoon, turbines at the Aishihik station remained idle as of press time today.

Generators are complex machines, said Patterson. Repair requires much more than flipping a few switches.

Over the course of the day, crews at the Whitehorse plant were incrementally bringing power back to the grid from the four hydro and seven diesel generators.

“Because it was such a massive outage it took several hours,” she said.

“If you bring a load on all at once the system can’t handle it and it will cause an outage again.”

While Patterson wasn’t sure if it had been put to use, there is also a diesel generator in Faro.

Many Yukon residents could have blown out the candles and flicked on their reading lamps sometime between 5:30 p.m. and 9:30 p.m. Sunday.

Some never had to go hunting for flashlights at all.

The Mayo to Dawson City power line is on another grid. This means the Mayo hydro plants are not tied to those on the Whitehorse-Aishihik-Faro system.

So, Yukoners on the Mayo to Dawson line could eat hot meals without firing up the wood stove.

Watson Lake is another self-sufficient community on its own diesel generator.

The blackout raised many serious questions for Haines Junction MLA and NDP energy critic Gary McRobb, who said he was sitting in the dark and in the cold until 10:30 p.m.

While crews did an excellent job to restore power, the outage itself highlighted larger underlying issues, he said.

“Yukoners deserve a full explanation of what went on here, and to get down to the truth of what’s going on here,” he said on Monday morning.

There have been issues with one of the turbines at the Whitehorse dam, he said, and now there are clearly problems at the Aishihik dam as well.

“It could be an issue of maintenance and repair over the past decade,” he said. “It could be that the system hasn’t been fully tested.”

Since the Faro mine closed down, the demand for electricity from the system has been relatively low, he explained.

This could be about to change, though.

The territorial government is proposing to build a power line from the Whitehorse grid to feed mines in Minto, McRobb said.

“The load on our system is about to increase, so our system is about to be stressed a lot more than it has been,” he stated.

“If there are production units and facilities that need work, the frequency of outages is bound to increase.”

Stopping short of asking Yukoners to stock up on slow-burning candles and batteries, McRobb said the government should proceed with caution.

“I’m suggesting we make sure our existing system is really up to speed before we start spending our money on further stressing the system by building more transmission lines.”

There can be serious repercussions to power outages as well, said McRobb, noting that it can be particularly difficult for seniors.

“It goes back to the people issue here. It puts lives at risk,” he said.

“Our dependency on electricity is well-integrated into our society and you don’t fully appreciate that until there’s a severe outage.”

Until the Aishihik turbines are pumping out energy again, Yukon Energy advises residents to conserve electricity.

With energy consumption peaking again at dinner hour, said Patterson, some areas may experience rolling blackouts.