The agency that oversees Alberta’s electricity system once again begged Albertans to cut their energy use as a life-threatening cold snap continued Monday morning. Here’s what you need to know: 

Fast action: Albertans responded quickly to “grid alerts” on the weekend when the Alberta Electricity System Operator warned in a cellphone blast that it might need to order rotating blackouts—despite lows below -40 C—as it dealt with a potential shortfall of 100 to 200 megawatts.

Everything is political: Alberta Premier Danielle Smith pointed out that the province’s renewable-energy installations weren’t much help, after dark and with little wind; Saskatchewan Premier Scott Moe emphasized that the 153 megawatts of power his province sent to Alberta came from fossil fuels. B.C. Energy Minister Josie Osborne noted that British Columbia sent 200 megawatts despite record demand at home; its electricity comes overwhelmingly from hydro dams.

Monday’s grid alert in Alberta ended by late morning as wind and solar generation picked up, though the system overseer was still worried about excess demand in the evening.

Nuclear option: Capital Power, the Edmonton-based utility descended from Epcor, said Monday it’s starting a feasibility study for “grid-scale” small modular nuclear reactors. The technology could ultimately produce greenhouse-gas-free energy for Alberta without the political baggage of solar and wind.

Grounded flights: The arctic conditions on the Prairies hit airlines after a mighty storm in the east had already wreaked havoc on their schedules. De-icing fluid stops working below -29 C, mechanical equipment on the ground seizes up and working outside gets dangerous. WestJet cancelled 153 flights on Saturday and another 120 on Sunday, and departure boards at the Calgary and Edmonton airports were riddled with delay notices and more cancellations.

Warming trend (relatively speaking): Temperatures are forecast to climb above -20 C in Alberta’s big cities in the next couple of days, and even above freezing in Calgary by the weekend … but with up to 15 centimetres of snowfall along the way.