There are two ways to interpret your question. We will therefore answer both possibilities.
Regarding peak consumption when it’s very cold, Hydro-Québec may ask the public to reduce or postpone using major appliances between 6 and 9 a.m. and between 4 and 8 p.m. during weekdays. Note that you pay the same rate at all times, regardless of when you use your appliances.
The peak times of our customers services call centre is generally during lunch hours Monday to Friday.