To date, several different agricultural and forestry biomass sources have emerged as current feedstock for conversion to bioenergy (fuels, power, heat) and bioproducts. Most notably, in the U.S., these include corn grain converted to ethanol and also soybean oil, waste greases, and fats converted to biodiesel. Additionally, forest residue and other wood sources are commonly burned or co-fired to produce biopower.
These are not the only biomass feedstocks being converted to various forms of bioenergy. Ethanol is currently produced from sugars found in grains (primarily corn, also sweet sorghum, and wheat) as well as sugarcane, potato skins, rice, and sugar beets. Biodiesel is currently produced from oilseed crops (primarily soybeans, also sunflowers, flax) and recycled greases and fats. A variety of forestry biomass sources are used for biopower. Other current sources for various types of bioenergy include agricultural residues and waste (e.g., logging residue, forest thinnings, animal manure, corn stover, wheat straw, rice hulls, fruit pits, etc.), urban wood waste, wood processing waste, pulping liquor, food processing waste, post-consumer residues, and landfill gas, among others.
Agricultural and forestry resources that have been traditionally used as sources of raw material for bioenergy and bioproducts will continue to play a major role in the emerging bioeconomy. The U.S. Department of Agriculture (USDA) and the Department of Energy (DOE) have committed to significantly enhancing the use of biomass as a source for biofuels, biopower, and bioproducts. A recent report from DOE and UDSA has estimated that more than 1.3 billion tons of biomass material could feasibly be available for annual bioenergy use in the U.S. by the middle of the century (Perlack, et al., 2005).
Many research efforts are underway to examine the potential for various new biomass crops to be developed for and used in the bioenergy sector, in addition to research efforts to further improve technologies and economics of using traditional biomass sources. The new crops being examined include herbaceous (grass) crops, non-wood fiber crops, and fast growing woody biomass crops, all with potential to be used for biofuels or biopower production. Additionally, some of these crops could be used to produce chemical compounds for bio-based products that can substitute for current petroleum-based products, along with rubber or resin crops.