Biomass is plant or animal material used as fuel to produce electricity or heat. Examples are wood, energy crops and waste from forests, yards, or farms. Since biomass technically can be used as a fuel directly (e.g. wood logs), some people use the terms biomass and biofuel interchangeably. More often than not, however, the word biomass simply denotes the biological raw material the fuel is made of, or some form of thermally/chemically altered solid end product, like torrefied pellets or briquettes.
Biomass power generation is based on biomass fuel and forest waste as raw materials, which are crushed and pretreated, and then sent to the biomass power generation boiler for incineration and power generation. The ash produced by combustion can be processed into fertilizer and returned to the field. Biomass power generation technology is currently one of the most common and effective methods of biomass energy application. In developed countries such as Europe and the United States, biomass power generation has formed a very mature industry and has become an important power generation and heating method in some countries.