Wood has been a traditional fuel for both domestic and industrial use. However, it produces a lot of smoke that can cause respiratory problems. Also, wood is obtained from trees. Thus, using wood as a fuel causes deforestation. Therefore, slowly wood is replaced by LPG, which is a liquefied form of petroleum gas. It does not give out smoke and other pollutants and is a cleaner fuel. Again, fuel efficiency of LPG is more than that of wood. The calorific value of LPG is 55000 kJ /kg, while that of wood is between 17000 to 22000 kJ / kg. Hence, LPG is favoured over wood.