[hwillis]

Depending on the car and the temperature you'd much rather be stranded in a Tesla (or another EV that works as well at low temperatures). A Tesla can run its heater on full blast for well over 12 hours. In ICE cars that don't have resistive heaters, the heat output is much lower at idle- think a civic or corolla. It can be risky to fall asleep in cars like this because you need to warm up the engine regularly or the cabin will become quite cold.

[terryf]

Having slept in quite cold temperatures in cars during longer trips quite a lot of times, just having the car idle over-night has always been enough to keep the cabin warm enough to not even need a blanket. Not talking about luxury cars with huge engines either. It also uses very little fuel. After 8 hours, you can see that the fuel gauge has moved, but only very slightly. I'm pretty sure a ICE car with a full tank can idle for several days before running out of fuel.