Other gases (such as the natural gas many of us use in our homes) make a good fuel for an internal combustion engine but do not possess this unique property. Thus, far less compressed but non-liquid gas may be stored in a tank of a given volume and the vehicle's range is severely reduced.

LPG (Propane and Butane) were first discovered in Pittsburgh USA by a Dr Walter Snellings as a result of a complaint. The complainant said that when a gallon of petrol was purchased it was practically half a gallon by the time he got it home. Dr Snellings began to investigate. He discovered the evaporating vapours were propane, butane and other hydrocarbons.