CNG is natural gas compressed to a pressure of 200-250 Kg/cm² (g) to enhance the vehicle
on-board storage capacity. Thus, the compressed form of NG is used as a fuel for transportation
The advantages of using CNG are varied and distinct.
Commonly referred to as the green fuel because of its lead and sulphur free character, CNGreduces harmful emissions. Being non-corrosive, it enhances the longevity of spark plugs. Due to the absence of any lead or benzene content in CNG, the lead fouling of spark plugs, and lead or benzene pollution are eliminated.
Increased life of oils
Another practical advantage observed is the increased life of lubricating oils, as CNG does not contaminate and dilute the crankcase oil.
Mixes evenly in air
Being a gaseous fuel CNG mixes in the air easily and evenly.
High auto ignition temperature
CNG is less likely to auto-ignite on hot surfaces, since it has a high auto-ignition temperature(540 degrees centigrade) and a narrow range (5%-15%) of inflammability. It means that if CNGconcentration in the air is below 5% or above 15%, it will not burn. This high ignition temperatureand limited flammability range makes accidental ignition or combustion very unlikely.
Low operational cost
The operational cost of vehicles running on CNG, as compared to those running on other fuels, iscomparatively low.