Biomass is a broader term used to describe all substances of plant and animal origin that are found on the surface of the Earth. In the context of energy biomass, this term is often used to describe substances of plant origin, yet the term “biomass” may refer to both animal and vegetable substances.

Assuming this fuel is managed sustainably, biomass is harvested as part of the crop reproduction process. This takes place as part of cultivation of land, forest and orchard management, forest logging, or a permanent planting program, when new plantings absorb carbon dioxide from the atmosphere at the same time as it is released in the combustion of previous harvests.