Structure:

Introduction: (up to 30 words) Write/explain briefly about CNG as a fuel

Body: (up to 100 words) Mention how CNG fuel is a cleaner source of fuel and may be a viable option to run vehicles.

Conclusion: (up to 30 words) Write about challenges associated with the shift/use of CNG fuel.

Supporting Points:

A natural gas vehicle (NGV) is an alternative fuel vehicle that uses compressed natural gas (CNG) or liquefied natural gas (LNG).

1. In a natural gas powered vehicle, energy is released by combustion of essentially methane gas (CH4) fuel with oxygen (O2) from the air to carbon dioxide (CO2) and water vapor (H2O) in an internal combustion engine.
2. Methane is the cleanest burning hydrocarbon and many contaminants present in natural gas are removed at source.

• Existing gasoline-powered vehicles may be converted to run on CNG or LNG, and can be dedicated (running only on natural gas) or bi-fuel (running on either gasoline or natural gas).

1. Diesel engines for heavy trucks and busses can also be converted and can be dedicated with the addition of new heads containing spark ignition systems, or can be run on a blend of diesel and natural gas, with the primary fuel being natural gas and a small amount of diesel fuel being used as an ignition source.
2. It is also possible to generate energy in a small gas turbine and couple the gas engine or turbine with a small electric battery to create a hybrid electric motor driven vehicle.

Challenges:

1. Convenient and cost effective gas storage and fuelling is a key challenge compared to petrol and diesel vehicles since the natural gas is pressurized and/or - in the case of LNG - the tank needs to be kept cold. T
2. he lower energy density of gases compared to liquid fuels is mitigated to a great extent by high compression or gas liquefaction, but requires a trade-off in terms of size/complexity/weight of the storage container, range of the vehicle between refueling stops, and time to refuel.