Name four gases commonly present in biogas. State two advantages of using this gas over fossil fuels.

The typical gases present in biogas are as follows:

1. Methane

2. Carbon Dioxide

3. Hydrogen

4. Hydrogen Sulphide

Biogas is more efficient as fuel as compared to fossil fuels in the following ways:

1. Biogas does not leave any ash and residue after combustion.

2. Biogas does not burn with a smoke and does not cause pollution.