---

Yes, microbes can be used as source of energy. The microbial action of certain microbes release gas. Biogas (predominantly methane) is produced from dung by the microbial action of methanogenic bacteria. Biogas is a mixture of gases produced by microbes and  is the rich source of energy. It is used as an energy resource for cooking and lightning purposes, also used in internal combustion engines to power pumps and electric generators.