The organic waste of agriculture, useless agricultural material, dung of the animals, domestic waste, the human excreta, the residue of the sugar factory, etc. are decayed (decomposed) and the gas thus obtained is called Biogas. It is prepared by chemical process with some bacteria. Here, methane and carbon dioxide gaes are released. Methane is a combustible gas. Biogas is an excellent fuel for cooking and for generating electricity. After using the biogas, we can get the organic manure afterwards. Thus energy and manure both can be obtained from biogas. The biogas is cheaper and easy to use. The gas which is produced only from the dung is called 'Gobar Gas'. The equipment which produces biogas and the manure is called 'Biogas Plant'.Uttar Pradesh ranks first and Gujarat ranks second in the production of biogas in India. Very large biogas plants are established at Rudatal of Daskroi taluka of Ahmedabad district and at Dantiwada of Banaskantha.
Its use is increased by establishing biogas plants individually and collectively.Lakhs of tonnes of wood and dung are used as fuels in villages. If biogas is used instead of it, the cutting of trees can be prevented. cleanliness of the villages can be increased and their shortage of domestic energy can be reduced.