What is the differences between LPG and CNG?

Answer 1

CNG is basically composed of methane whereas LPG is a mixture of propane, butane and other chemicals.

Another important difference from a physical point of view is that

CNG does not liquefy under high pressure - it remains a gas, unless it is cooled down to at least - 164°C. LPG on the other hand becomes liquid when it is compressed or when it is cooled down (therefore the name "Liquefied Petroleum Gas").

CNG directly comes from a gas field. The only process, which sometimes needs to be done, is filtering the gas. But usually, the gas can be used as a fuel right away after the compression process. LPG, however, is an artificial product. It is a mixture of the above-mentioned gases. Hence, these gases need to be blended, before they can be used as fuel.

CNG has a greater part of Hydrogen and is therefore lighter than air (this attribute in fact makes CNG very safe: once there is a leak in the system, the gas will simply be released to the atmosphere). LPG on the other hand, is twice as heavy as air. This gas is usually a by-product which accumulates from the oil drilling as well as the refinement of oil.

in addition to what is above-another difference is simply their use. CNG is mostly used in vehicles while LPG is used for cooking in place of electric stoves.
LPG is abbreviation of low pressure gas and CNG is compressed natural gas
CNG mainly consists of Methane(CH4), whereas LPG mainly consists of Propane(C3H8) and Butane(C4O10)