ABSTRACT
Biomass includes all plant and animal living matter. The most commonly found form of biomass resources is plant biomass from agricultural food production. Other sources of biomass include forestry resources and residue and animal manure from conned animal production operations. Each country will have their own biomass residue accumulating in agricultural lands, such as rice straw from rice-producing countries and rice hulls accumulating in rice mills. Cotton-producing states such as Texas would have abundant cotton gin trash that accumulates in cotton gins. Plant biomass resources are produced via the process of photosynthesis, which makes use of the sun, arable land, and water. The conversion of solar energy into biomass per unit area is quite low and inefcient. However, because of the vastness of land and water bodies available for photosynthesis, some 1260 EJ (1018 J) of energy is still produced each year (Boyle, 2004). The world’s annual primary consumption is 424 EJ (Boyle et al., 2003), which is about three times the energy stored in biomass each year. The United States’ annual energy consumption in 2009 was around 100 EJ (95 quads, see Example 1.1 for unit conversion), representing about a quarter of the world’s energy consumption
(U.S. Energy Information Administration [EIA], 2010). The United States is also a net energy importer because the annual energy production from all sources totals 77 EJ, with 8 EJ coming from renewable energy. The contribution of biomass energy to this energy mix is approximately 4%.
