Major Fuels are:
Petrol (gasoline) - Quality of Petrol is measured by Octane number. It is a measure of the resistance of gasoline against detonation or pre ignition of the fuel in the engine. Octane is not a measure of power and has no connection with power rating
Diesel - Quality of Diesel is measured by its cetane number. A higher cetane number indicates that the fuel ignites quickly and more readily when sprayed into hot compressed air. Fuels with higher cetane numbers are normally “premium” diesel fuels with additional cleaning agents and some synthetic content.
LPG (Liquefied Petroleum Gas) – It is also known as Auto Gas and third most popular automotive fuel used in the world. Emission of harmful gases are very less in terms of LPG. It is widely used in other part of the world but less popular in India
CNG (Compressed Natural Gas) – CNG is made by compressing natural gas (which is mainly composed of methane, CH4). It is stored and distributed in cylindrical containers. CNG is used in petrol/diesel engine automobiles which have been modified with kit OR factory fitted which were manufactured for CNG use. CNG is increasingly used in Asia-Pacific region (especially in India and the Indian capital of Delhi), and other large cities like Ahmedabad, Mumbai, Kolkata, Chennai—as well as cities such as Lucknow, Kanpur, etc.
Hybrid Batteries (for Electric vehicles)
Hydrogen Fuel Cell (yet to be commercialised)