The power utility said it expects power consumption to exceed 39,000 megawatts, which would set a new historic peak.
The previous record was set around this time last year — 38,797 megawatts on Jan. 23, 2013.
In order to reduce the burden on the power grid, Hydro-Québec is asking members of the public to reduce their electricity consumption during peak hours.
"In advance a big thank you for everyone. It's not an easy thing to do when it is cold like this to think about turning down your heat. But it really can make a big difference collectively for all of us in terms of costs and that is really something we pay attention to," said Hydro-Québec spokesman Gary Sutherland.
He said power use can go up significantly in a cold snap because houses become less efficient at insulating their heat when the temperature stays low for several days.
He said during last year's peak, the utility managed to skim off 600 megawatts when residential customers reduced their consumption.
"That is a significant percentage really. That, accumulated with other measures such as large power consumers, really does make a difference on the system," Sutherland said .
Hydro-Québec is also calling on government building managers and industrial customers to reduce their power use.
The power utility is also following its own advice, and setting an example by reducing heating and lighting in all its Quebec buildings. At its head office in Montreal, the big "Q" logo and the Mousseau mural will also be turned off.
When should I reduce my power consumption?- Wednesday: 6 a.m. - 9 a.m. and 4 p.m. - 8 p.m
- Thursday: 6 a.m. - 9 a.m. and 4 p.m. - 8 p.m
Tips on curbing your energy use- Lower the thermostat by a degree or two in all rooms, especially in those that are not being used.
- Postpone using appliances such as dryers and dishwashers by a few hours.
- Limit the use of hot water as much as possible.