The calorific values of petrol and CNG are 45000 kJ/kg and 50000 kJ/kg respectively. If you have vehicle which can run on petrol as well as
CNG, which fuel will you prefer and why?
We will prefer CNG (Compressed Natural Gas) because the calorific value of CNG is higher than that of petrol. CNG will produce large amount of
heat energy than petrol.
At the same lime, it produces the least air pollutants. CNG will be more economical.