In the hours leading up to an outage that left thousands of Whitehorse residents in multiple neighbourhoods without power as an extreme cold snap took hold on the Yukon, the territory set a record-high for electricity demand, according to the Yukon Energy Corporation.
In a tweet on Dec. 19 at 5:45 p.m., ATCO Electric Yukon announced crews are responding to an unplanned outage, with no estimated time of restoration.
At 9:58 p.m., the utility provider tweeted that power had been restored to all customers.
In an email statement on Dec. 20, a communications representative for ATCO Electric Yukon said the outage started at 5:30 p.m. and was restored by 9:50 p.m. It impacted 3,360 customers in areas including Whistle Bend, Laberge, Crestview, Kulan, parts of Takhini and Range Road, Alaska Highway West and Klondike Highway North.
“During cold days like today and yesterday, the demand for electricity increases and puts pressure on the system,” reads ATCO’s email statement.
ATCO Electric Yukon and the Yukon Energy Corporation said the outage was caused by an overloaded breaker at the Takhini substation that tripped due to protection settings.
Before the power went out on the afternoon of Dec. 19, the Yukon Energy Corporation had posted on Facebook that Yukoners needed a record 117.1 megawatts of electricity, topping the previous record, set on Jan. 6, by one megawatt.
In the Facebook post, Yukon Energy Corporation is also asking Yukoners to “help us beat winter peaks and reduce the use of diesel by reducing the amount of electricity you use during periods of high electricity demand.” Peak times are typically between 7 a.m. and 9 a.m., and 5 p.m. and 7 p.m. from Monday to Friday, according to the post.
The post suggests using a block heater timer on vehicles, delaying the use of major appliances and turning down the thermostat by a degree or two.The corporation said more than 90 per cent of electricity generated in the Yukon comes from renewable resources, although the territory relies on hydro, liquefied natural gas and rented and permanent diesel resources to produce electricity during periods of high electricity use each winter.
Hours later, the breaker tripped.
In an email statement the following day, the communications manager for the Yukon Energy Corporation said approximately 46 of 117 megawatts was thermal usage (which refers to liquefied natural gas and diesel) and 71 megawatts was hydro usage.
“While we are working to reduce the likelihood of this happening again, we can all do our part by reducing electricity use during peak hours.”
In the email statement, the communications manager for the Yukon Energy Corporation said the corporation has adjusted the settings at the Takhini substation to help prevent future outages.
In a release on Dec. 20, the official Opposition said Yukoners had been wondering why this outage happened in the first place and what is being done to prevent outages from happening again.
In the release, Yukon Party MLA for Porter Creek Centre Yvonne Clarke said that while ATCO Electric Yukon had provided ongoing updates on social media and responded to Yukoners’ concerns, the Yukon government’s silence on the matter is “very concerning.”
“I’ve heard from constituents that had to pack up young children to join friends or families that had heat, because they were worried about the temperature dropping in their homes,” she said.
“There was never any communication about where Yukoners who had to leave their homes should go, or whether centralized warming centres were being planned.”
The Yukon Party saw an opening to take a jab at the territorial government’s energy strategy that currently involves relying on rented diesel generators for peaking electrical generation.
In the email statement, the Yukon Energy Corporation communications manager said that renting diesel generators each winter is necessary until new sources of dependable capacity can be built to meet growing peak demands for electricity.
Yukon Energy officials appeared as witnesses before the Yukon Legislative Assembly on Nov. 17.
When asked by the Yukon Party about the reliability of the rentals, Andrew Hall, president of the Yukon Energy Corporation, said the rentals are less reliable than a permanent diesel plant.
Hall noted the decision to use temporary diesel rentals as an interim strategy was “very deliberate” given a permanent plant would “not be able to attract any federal funding of any form” and “ultimately striving for 97 per cent renewable on our grid.”
In the release, Scott Kent, the Yukon Party’s critic for Energy, Mines and Resources, blamed the Yukon government for not investing in “reliable” power supply.
“The flawed energy policies of the territorial Liberals has left the Yukon with a dangerously vulnerable electrical grid, and the recent blackout has given Yukoners a sense of what that means for them,” Kent said.
“Instead, they have banked Yukon’s energy future on uncertain projects like the Moon Lake hydro project which is likely at least a decade away.”
The potential future Moon Lake project is described on the Yukon Energy Corporation’s website as a “reversible hydroelectric facility” where water is pumped uphill into a reservoir, then water flowing back down the hill is harnessed to generate electricity.
Energy, Mines and Resouces Minister John Streicker said this outage was not about supply or backup power.
Streicker explained the Yukon government does not take the lead in a situation like this. In fact, he said, the city and ATCO Electric Yukon take the lead in these types of situations in Whitehorse.
“If temperatures are cold and power is out for more than four hours, then there’s [an emergency] protocol in place to contact [Yukon government’s] emergency measures, which was done,” he said.
According to Streicker, the city was weighing whether to “stand up” when the power returned.
“I think that the outage is, of course, a concern,” he said.
“But it looks to me like the systems that we put in place to try and address it were doing what they were supposed to do.”
On social media on Dec. 20, ATCO Electric Yukon said its crews were investigating the cause of another outage in Pelly Crossing.
Contact Dana Hatherly at dana.hatherly@yukon-news.com