LPG stands for Liquefied Petroleum Gas. The term is widely used to describe both Propane and Butane.
The term "liquefied gas" may seem a contradiction in terms yet liquidity is the unique character of LPG that makes it such a popular and widely used fuel. At normal temperature and pressure, LPG is gaseous. It changes to a liquid when subjected to modest pressure or cooling which means it can be easily stored in bulk tanks or portable cylinders so providing energy wherever it is needed. In liquid form, the tank pressure is about twice the pressure in a normal truck tyre, which means it is very safe when properly handled.
LPG is a by-product of two large energy industries: the processing of natural gas liquids and the refining of crude oil. It used to be burned off and wasted but after its value as a versatile low carbon fuel was recognised it quickly became established globally as a widely available exceptional energy source that is perfect for a wide range of applications from providing heat in homes and industry to powering the Olympic flame.
The trade association for the LPG industry in the UK