Blackouts caused by systemic problems

A barrage of power outages has forced the Yukon Energy Corporation to admit that, despite a doubling of capital spending, its grid is antiquated and in need of modernization. The past is weighing heavily on the publicly

A barrage of power outages has forced the Yukon Energy Corporation to admit that, despite a doubling of capital spending, its grid is antiquated and in need of modernization.

The past is weighing heavily on the publicly owned utility after 17 equipment-related and 18 nature-related power outages blacked out the southern Yukon in 2008.

The reason? Yukon Energy just can’t keep up with the repairs needed after power usage surged in the early 2000s.

“A number of years ago, the system wasn’t being used to its full extent,” said president David Morrison.

The electricity grid is more than half a century old in some parts and demand remained very low for decades.

“We had tons of surplus hydro and we didn’t have very many customers,” said Morrison. “Things were pretty tired and, in my opinion, everyone got a little complacent.”

There was no urgency to repair old diesel generators that weren’t being used because they weren’t experiencing any wear.

“I don’t think that was the correct analysis in the end,” he said. “Because when we did need to run the diesel plants, we had lots of problems.”

In 2002, the Whitehorse hydro station produced 69 gigawatt/hours. In 2003, that figure jumped to 208 gigawatt/hours. Secondary sales and sales to Yukon Electrical Company Ltd. also doubled that year and continued to grow.

Condominiums, big-box stores and a new mine marked a new era for Yukon Energy.

The Whitehorse-Aishihik-Faro grid was under more stress than ever before, and that meant more repair work.

But the repairs started too late.

In 2005, Yukon Energy tendered contracts for engineering firms to analyze the grid to see what needed repair. Different firms looked at transmission and generation sections of the grid, and based

on those findings Yukon Energy wrote up a capital spending plan.

The company applied to the Yukon Utilities’ Board to double its amount of capital spending to about $8 million from $4 million. The extra funds would allow it to beef up monitoring, buy new equipment and speed up the replacement cycle.

For a few years, things looked rosy. The fourth hydro generator in Whitehorse was refurbished in 2007 and the repair cycle seemed to be on par with the increased usage.

“We rewound the generators at Mayo and we rewound both the generators at Aishihik,” said Morrison. “We do major overhauls of engines after so many hours of use and we go through that process as a matter of course.”

Then 2008 came along.

Substations, governors and power lines failed, causing outages from minutes to hours in length, and from single homes to grid-size in magnitude.

On Thanksgiving weekend, a tree caused an outage on Friday, generator four in Whitehorse caused an outage on Sunday and generator three at the same plant shut down power on Monday.

The second and third outages were grid-wide.

The Dawson-Mayo grid wasn’t spared either. It had 23 unplanned outages last year, some of which were due to lightning strikes in the summer. But the old transmission lines caved in a few times, too.

“That has been an unfortunate legacy of constructing that line,” said Morrison.

The outages were a public relations disaster for a company that was trying to promote its decrease in power rates to residential customers. An impromptu news conference was called last week after the Aishihik substation shut down the grid for nearly an hour.

“Hopefully, we’re at a point where we got most of these (repair) issues dealt with and we hit the peak last year,” said Morrison. “We had some equipment failures that we just didn’t foresee.”

“We weren’t spending enough in the years prior to (2005),” he said.

“We’re still trying to play catch-up.”

The increase in spending is the new playing field and will likely continue indefinitely, said Morrison. The first four years haven’t gone so well, and Yukon Energy is taking a new look at the plan for the next few years.

Each of the six hydro generators on the southern grid will get one month of annual maintenance over the next six months from March until September as planned. Maintenance is typically done when Yukon Energy can afford to have the generators offline in the summer.

But the governors on generators three and four in Whitehorse were recurring culprits in outages last year, and will likely be repaired or replaced during maintenance.

The governors are the problem children of hydro equipment, costing the utility money and requiring consultant advice over and over again.

“We brought in everyone we could think of to look at those governors,” said Morrison. “We brought in experts from BC Hydro. We brought in consultants from engineering firms. Every time we fixed them we said, ‘The governors are fixed,’ then a couple of months later, the governors weren’t fixed anymore.”

Last fall, Yukon Energy brought in engineers from L&S Electric based out of Wisconsin.

“We haven’t had a problem with those governors since those guys looked at them,” said Morrison.

“I hate saying it because I’m probably going to jinx myself.”

At the Aishihik hydrostation, the substation is prone to breakdown.

“Part of the problem at the substation is old equipment and detecting some failure in this is a timing thing,” said Morrison.

Monitoring can miss a problem because it’s always done in a cycle. A piece of equipment can break down just after getting looked at and won’t be caught before the repair cycle comes around again, he said.

Yukon Energy is also hoping to speed up its diesel generator repair. It tendered a company to repair a generator at Faro last year, but only found out after the fact that it couldn’t provide the parts needed. That generator has been offline for a year and another at Whitehorse has been undergoing maintenance since the fall.

Both should hopefully be finished next month, said Morrison, and other diesel generators are scheduled for maintenance in 2011 and 2012.

The sad part about the Yukon’s electricity grid is that it has full backup capacity. The massive interconnected grids down south can suffer massive blackouts because new power can’t be quickly generated at other sources to bring power back on.

But in the Yukon, there are enough offline generators to take the power load if the main generators fail.

So while a system is already in place to prevent the cascading effect — which is when the instability of an outage cascades from one section onto the next — Yukon Energy hopes to have a study done this year to install a more modern protection system.

It would quickly switch on new generators when another source breaks down, in a sense making the grid smarter and faster on its feet. The grid would sacrifice small sections of the grid so that outages don’t sweep across the Yukon.

“It’s an engineering exercise and it will take a couple of months,” said Morrison. “The study will cost $30,000 or $40,000 and out of that we’ll get specific prices from there.”

It will require new programming and, potentially, new equipment, he said. Right now, some breakers are manual and need to be turned on by hand.

In 2009, Morrison is aiming to cut outages in half. An industry standard for outages does exist, he said, but it’s more suited for large, supergrids.

In his opinion, four or five unplanned outages would be acceptable per year.

It’s a lofty goal that remains to be seen, but the utility now realizes it could have been there now if it started the repair work a little earlier.

“We should have probably started six years ago, not three or four years ago,” said Morrison.

Contact James Munson at

jamesm@yukon-news.com.