LPG composition
LPG is a clean source of energy and is mostly obtained from natural gas and oil production. It is a side-product of the mining process.

Its chemical composition:

Propane / C3H8 (43%)
Butane / C4H10 (~55%)
Pentane (2%)
Methane (<1%)
Ethane (<1%)
Stored in a liquefied state, 1 liter of LPG is as efficient as 270 liters of gaseous energy (natural gas).