Biomass may mean the biodegradable fraction of products, waste and residues from agriculture (including vegetable and animal substances), forestry and related industries, as well as the biodegradable fraction of industrial and municipal waste. Biomass may be used to produce bioenergy.
Oil and coal are the ultimate forms of biomass – they result from the decay of biological substances over millions of years, concentrating the available energy. But, on a much shorter timescale, plants such as sugar cane, cassava, trees, and kelp, can be used to produce fuels or chemical feedstocks.
Biomass may also refer to the total mass (excluding water content) of the plants and/or animals in a particular place. The term is often used to refer to the totality of living things on Earth; or those occupying a part of the Earth, such as the oceans.
Biomass energy, or bioenergy, is energy produced by the conversion of biomass directly to heat, or to a liquid or gas that can be converted to energy.
Biomass gasification is the conversion of biomass into a gas, by biogasification or thermal gasification. In the latter, hydrogen is produced from high-temperature gasifying and low-temperature pyrolysis of biomass.