what is fuel efficiency class 8

Fuel efficiency refers to the ability of a vehicle or any other device to extract energy from the fuel being used. In other words, it is the measure of how efficiently a fuel converts one form of energy to another. Fuel efficiency is expressed in terms of kilometers/liter. The farther a vehicle runs on a measured volume of fuel, the better is its fuel economy. Fuel efficiency is calculated based on the calorific value of the fuel being used. Calorific value is defined as the amount of energy produced when complete combustion of 1 kg fuel takes place. The calorific value of LPG is higher than that of wood, so LPG is considered a more efficient fuel than wood. The efficiency with which the heat produced by fuel is converted to mechanical energy is known as fuel efficiency.