Question

Why is biogas better fuel then cow dung cakes?

Answer 1

because burning of cow dung cakes produces smoke, and cause pollution whereas burning of biogas do not cause pollution.
burning of dung cakes left ash behind but biogas does left anything on burning
thus, biogas is better fuel than cow dung cakes

Answer 2

Why is biogas better fuel then cow dung cakes?

1. It doesn't leave any ash after burning.
2. It burns with smokeless flame.
3. It has higher calorific value than dung-cake, wood & coal.
4. It is much cheaper than most of the common fuel.
5. Use of Biogas as a fuel will save forests & fossil fuels.