Report: Achieving Sustainable Production of Agricultural Biomass for Biorefinery Feedstock
Can American farmers feed the world and produce large supplies of biomass for a growing biorefinery industry? The answer is yes. Demand for alternative feedstocks for fuels, chemicals and a range of commercial products has grown dramatically in the early years of the 21st century, driven by the high price of crude oil, government policy to promote alternatives and reduce dependence on foreign petroleum, and efforts to reduce net emissions of carbon dioxide and other greenhouse gases. This is particularly true for renewable feedstocks from agricultural sources.
For example, in the United States, ethanol production, primarily from corn grain, has more than tripled since 2000. Annual U.S. production of ethanol is expected to exceed 7 billion gallons by 2007, displacing nearly 5 percent of the projected 145 billion gallons of U.S. gasoline demand. Sales of biobased plastics are also expanding. The growing availability of economically competitive biobased alternatives to petroleum can be attributed in large part to advances in the production and processing of corn grain for industrial uses. Steady increases in corn yields made possible by agricultural biotechnology continue to expand the supply of available feedstock, while rapid advances in the relatively new field of industrial biotechnology—including development of genetically enhanced microorganisms (GEMs) and specialized industrial enzymes—have greatly enhanced the efficiency of ethanol production. Industrial biotechnology has also yielded a range of new biobased polymers, plastics and textiles. The U.S.
Department of Energy (DOE) has identified 12 building block chemicals that can be produced from biomass and converted to an array of high-value products.
The National Corn Growers Association projects that with continued advances in biotechnologies that boost corn yield, as much as 5.95 billion bushels of U.S. grain could be available for ethanol and biobased products by 2015—while continuing to satisfy food, animal feed and export demands. That amount of corn could produce nearly 18 billion gallons of ethanol, enough to meet over 10 percent of projected U.S. gasoline demand.
But if ethanol is to expand into a more widely available alternative to gasoline, new feedstock sources will be required to supplement high-efficiency production from grain. A robust sustainable supply chain for cellulosic biomass—biological material composed primarily of cellulose, such as agricultural and forestry residues, grasses, even municipal solid waste—is needed.
A recent comprehensive analysis by DOE and the U.S. Department of Agriculture (USDA) found that “in the context of the time required to scale up to a large-scale biorefinery industry, an annual biomass supply of more than 1.3 billion dry tons can be accomplished.” Nearly 1 billion dry tons of this could be produced by American farmers, enough to meet the DOE goal of 60 billion gallons of ethanol production and 30 percent displacement of petroleum by 2030.