(i) Biomass is a renewable source of energy and hydroelectricity is also a renewable source of energy.
(ii) The use of biomass by burning causes air pollution but the use of hydroelectricity does not cause any pollution.
(iii) Biomass gives heat energy which can be used for cooking and heating only. On the other hand, hydroelectricity can run all types of electricical appliances.
(iv) Biomass energy can be obtained without using any special device but hydroelectricity can be produced only by establishing hydro-power plants
