Have you ever found yourself without access to hot water?? Go out and buy a Bucket Heater. These 1,000 watt heaters plug into a standard wall outlet and will heat water to 150 degrees in 12 minutes. They sell for about $50 online.
Obviously use common sense when heating water – especially if the bucket will be left unattended or located near small children – and never run the heater without water in the bucket.