If the power goes out and your home is all electric it can become a matter of life and death. You should have a backup heat source of some kind, even if it is just candles, in case your power goes off. For extreme climates an emergency heater such as the Mr. Heater,  Buddy heater series that is designed for indoor use. There are kerosene heaters for emergency use as well. You should never, ever try to heat your home with any kind of outdoor barbecue grill or improvised heater. For more see Emergency Heating Methods