Biomass is primarily the conversion of manufacturing by-products into electricity.
These by-products can include wood chips and fragments, leftover sugar, animal manure and anything else that’s burnable.
Biomass can also include materials produced specifically for the production of energy (e.g. corn ethanol).
The biomass is burned and the heat energy is turned into electricity. Biomass is a great way of disposing of products that might otherwise become waste; but is unlikely to become a primary producer of our world’s energy needs.