The input and costs involved in growing and harvesting the crops or in collecting the feedstock and delivering it to a biorefinery for production of liquid transportation fuels.
The land-use, agricultural, price, greenhouse gas, and other environmental implications of biomass production for liquid fuels.
Research and development (R&D) needed to advance production of biomass feedstock for transportation fuels.
The chapter examines the quantities of different types of biomass that can be harvested or produced while minimizing competition between food and fuel and minimizing adverse environmental effects. It also assesses the total costs of various feedstocks that will be delivered to a processing plant for conversion to biofuel. The panel considered societal needs on the basis of recent analyses that have explored tradeoffs between using land for biofuel production and using it for food, feed, fiber, and other ecological services that land resources provide.
Biofuel produced in the United States is overwhelmingly dominated by ethanol made from corn grain; biodiesel derived from soybean oil makes up most of the remainder. In the 2007 crop year (from September 2, 2007, to August 31, 2008), 3.0 billion bushels of corn, or 23 percent of the year’s harvest, was used to produce 8.2 billion gallons of ethanol (NCGA, 2008). Around 450 million gallons of biodiesel were also produced, about 90 percent of which was derived from the oil extracted from 275 million bushels of soybean, 17 percent of the year’s harvest (USDA-NASS, 2008a; NBB, 2008). On an energy-equivalent basis (in British thermal units), corn grain ethanol and soybean biodiesel together made up 2.1 percent of the liquid transportation fuel used in the United States in 2007 (EIA, 2008).
The social, economic, and environmental effects of domestic biofuels have been mixed. Diverting corn, soybean oil, or other food crops to biofuel production could induce competition among food, feed, and fuel, but increases in crop price have helped to revive rural economies. From the perspective of farmers and small rural communities, development of ethanol plants has created greater local demand and higher prices for corn grain (and for soybean through parallel efforts associated with production of biodiesel). Local investment in and control of these plants have also provided well-paying employment opportunities