Imagine a world where there is no need for gasoline to run your car. You drive a car that never runs out of fuel. When you get stuck in a snow drift you simply turn off the drive engine, turn up the heat, get some food from the refrigerator in the back seat and wait to be rescued. Conversely, if you break down in the desert, you turn off the drive engine, turn up the air and get a cold drink out of the refrigerator.