Gas is made in the same way as petroleum and is also trapped between layers of rock. Natural gas is tapped, compressed and piped into homes to be used in stoves and hot water systems. LPG (Liquefied Petroleum Gas) is made from crude oil. It is used for cooking and heating in homes, industrial heating in boilers, kilns and furnaces, and for camping and caravanning appliances. LPG can also be used as an alternative to petrol as an engine and transport fuel. Using LPG reduces greenhouse gas emissions from a vehicle by up to 20 per cent.