Got it. So just make sure your vehicle is constantly consuming energy and you'll never have an issue... unless the power is out for an extended period of time.
Want to see how quickly the petrol supply line breaks down in an emergency? We had severe shortages for a month after an earthquake. People hoarding fuel contributed significantly, at least you can't hoard electricity.
Also, electricity supply isn't prone to supply shocks when Russia invades Ukraine, or the Saudis want to flex their muscles.
Letting the car consume a small amount of constant electricity to keep the battery above freezing is thankfully not very expensive compared to a standard space heater (usually 1.5kW at 720 hours a month, costing $150 a month in Seattle).
Defrosting and toasting the cabin to 92F in freezing conditions usually burns about 1.2kWh to 3kWh while plugged in, but that is just a few tens of cents (or free depending on the charger) to get nearly instantly toasty and ready to drive.
No, I was trying to convey that it costs significantly less than keeping a space heater running 24/7 (which would cost about $150 a month at 14 cents per kilowatt hour).
$10 to $30 a month in power use to keep your battery toasty in the dead of winter isn't too bad a price IMO
Driving with an iced over window impairing visibility is illegal in most places, you have to address this with defrosting and perhaps scraping before moving the vehicle.
Idling combustion vehicles is bad, but sometimes it's a necessary evil to ensure visibility so the driver can avoid harming other road users.