The latest wintry blow to the East Coast got me to thinking about something. I've never been in the situation myself of being stuck out on a frozen road, but you often hear the advice to run the car's engine for 10 minutes every hour for warmth. Has anyone actually done this?

I ask because I'm curious if 10 minutes is enough time to warm up the engine enough to produce a usable amount of heat? I would think an engine could become quite cold in 50 minutes in sub-freezing temps.

Anyone have any idea if your typical alternator can mostly recharge the power lost to start the engine in just 10 minutes? I'm also concerned that with cars getting stuck for 10+ hours, a cold-weakened battery could eventually get too drained by following this hourly warming schedule.