In my van I use ½ gallon milk jugs filled about 85% to allow for freezing. I also have a hobo wood stove made from a V-8 juice can, a metal pot and a few fire starters. This way I have water and can heat it or cook anyplace. It’s always easy to find small twigs or wood debris to burn.

The reason for using the milk jugs is that they are free, hold a good amount of water and if the water is froze it’s easy to cut the plastic off the ice and put it in the pot to melt. But for most of the winter they don’t freeze 100%.