Question: how much is a gj of gas?
Answer: One gigajoule (GJ) equals one billion joules (J). A gigajoule of natural gas is about 25.5 cubic metres at standard conditions. One gigajoule of natural gas is approximately equivalent to 27 litres of fuel oil, 39 litres of propane, 26 litres of gasoline or 277 kilowatt hours of electricity.