I heard that in some cold snowy places it's recommended to keep a few thick candles in your car in case you get stuck in a blizzard. Those can burn for a long t

I heard that in some cold snowy places it's recommended to keep a few thick candles in your car in case you get stuck in a blizzard. Those can burn for a long time, light helping someone find you (say, at night), and they can warm you up a bit, maybe you can even get you some warm tea. That surprised me. Reading this adds to that feeling of surprise, and gives a clearer idea of how much heat they emit. I say it's a good post, if one reads it right. (It must be clear to most people that it's taking shortcuts in reasoning about air quality, so you must be mindful of the context you apply this to.)