When natural gas is compressed it is called Compressed Natural Gas (CNG). The gas present above oil layer in oil wells is called natural gas. CNG has less amount of carbon and hence is produces negligible amount of cabron monoxide or carbon dioxide on combustion. So, CNG is more environment-friendly than other petroleum products.
| LPG |
CNG |
| Liquefied petroleum gas is obtained after fractional distillation of crude oil. |
CNG is obtained from natural gas from oil well. |
| LPG is heavier. |
CNG is lighter. |
| LPG is less safe; it spreads near ground on leakage. |
CNG is much safer; it spreads in air on leakage. |
| LPG is mainly used as domestic fuel. |
CNG is mainly used as fuel for automobiles. |
