It’s been reported alternatively as “undergoing scheduled maintenance”, “undergoing unscheduled maintenance”, or “system failure due to cold”. Scheduled maintenance is BS, no one schedules that for peak seasonal demand times. Who knows about the other two.

With the market setup in Alberta, those plants going down caused a spike in electricity spot prices. Generators can make a windfall profit in tight supply times. Residences without contracts will see their price go to something like 32¢/kWh. With the way the Alberta market rules are set up now, there are no penalties for generators voluntarily shutting down in order to bump prices. It’s basically the same market manipulation that Enron was pulling twenty years ago.

Alberta has the highest provincial electricity costs, on average 25¢/kWh, Saskatchewan is second at 20¢/kWh, with the others trailing off from there. Manitoba is something like 10.8¢/kWh and Quebec is cheapest at 8¢/kWh. (typical costs for first 1000kWh including distribution and other fees)