Natural gas is the fastest growing primary energy source in the world. Because it is a cleaner fuel than oil or coal and not as controversial as nuclear power, gas is expected to be the fuel of choice for many countries in the future. Positive contribution of NG on environmental pollution must also be considered in economical aspects. NG is widely available. CO2 emission of NG is lower than both diesel fuel and gasoline, which makes NG engines favorable also in terms of the greenhouse effect. The correlation equations for production and consumption trends of natural gas (VNG) versus year (Y) are: For production: VNG=61.1374Y-120382.6 For consumption: VNG=58.5055Y-115218.5.