Alberta Institutes Rolling Blackouts amid Soaring Summer Heat, Plant Outages

Utilities in the Canadian province of Alberta were on Monday forced to institute rolling blackouts as soaring summer temperatures drove demand for electricity to an all-time high and six generators–four coal plants and two natural gas plants–entered unplanned outages.

The Alberta Electric System Operator (AESO), an entity that leads economic planning an operation of the region’s interconnected power system, said on Tuesday that the province saw an all-time summer record of 9,885 MW at 2 p.m. on Monday, breaking the previous summer record of 9,552 MW set on July 18, 2011. The last time Alberta saw rolling blackouts was on July 9, the same day, in 2006.

The four coal plants and two gas plants in different parts of the province suffered unrelated problems, AESO said, saying only that they were "all forced, all unplanned and all unpredictable, unforeseeable." The plants were owned by four different power companies. Three of six of the plants had ramped up by late afternoon.

The rolling blackouts hit Edmonton, Calgary, Red Deer, and Lethbridge, where temperatures soared over 30C (86F) on Monday. In Lethbridge, blackouts lasted for a total of three hours in various areas of the city. In Calgary, attendees of the ongoing Calgary Stampede were left stranded above the grounds in a Skyride, a popular ride resembling a chairlift around the Stampede Park’s grounds, for an hour. 

Demand was expected to soar further this week, but "barring further unplanned loss of generation, the system is expected to have an adequate supply cushion for peak periods," AESO said.

Alberta’s Market Surveillance Administrator, an electricity market watchdog, has planned a full review of the incident, which led a spike in spot power prices to the maximum C$1,000/MWh from C$11 MWh earlier on Monday. "We’re always on the lookout for anomalies and this would definitely qualify, but I don’t want to suggest right now that there’s been any conspiracy or collusion," Harry Chandler, head of the entity that serves as an electricity market watchdog, told the Calgary Herald. 

Alberta’s electricity system was deregulated in the mid-1990s and increases in power prices have become a talking point for the New Democrats, a left-of-center political party, who are calling for a return to a regulated system.

Sources: POWERnews, AESO, Calgary Sun, Calgary Herald