Biomass is any organic material made from plants or animals. Domestic biomass resources include agricultural and forestry residues, municipal solid wastes, industrial wastes, and terrestrial and aquatic crops grown solely for energy purposes.
Biomass can be converted to other usable forms of energy and is an attractive petroleum alternative for a number of reasons. First, it is a renewable resource that is more evenly distributed over the Earth's surface than are finite energy sources, and may be exploited using more environmentally friendly technologies.
Agriculture and forestry residues, and in particular residues from paper mills, are the most common biomass resources used for generating electricity and power, including industrial process heat and steam, as well as for a variety of biobased products. Use of liquid transportation fuels such as ethanol and biodiesel, however, currently derived primarily from agricultural crops, is increasing dramatically.
For more information on Biomass visit the U.S. Department of Energy