Submitted to: Forage Focus
Publication Type: Trade Journal
Publication Acceptance Date: March 14, 2007
Publication Date: March 20, 2007
Citation: Russelle, M.P. 2007. Alfalfa biomass: energy benefits of alfalfa vs. corn. Forage Focus. p. 2-3. Technical Abstract: Corn grain ethanol production is rapidly expanding, but grain crops cannot provide enough alternative fuel so the idea of lignocellulosic biomass has gained popularity. Woody species, grasses like switchgrass, and more recently mixed prairie species are the typical plants mentioned in relation to biomass production. They have their place on marginal soils and landscape positions, but on good agricultural land, alfalfa provides great opportunities in biomass production systems. This perennial forage legume benefits ground and surface water quality, soil quality, and crop rotations, and provides excellent wildlife habitat with proper management. In addition, alfalfa provides nitrogen to the next crop of corn, reducing both the cost and energy requirement for corn production. Corn yields are often higher after alfalfa than after corn or soybean. Because they are less dense than grains, biomass crops likely will be grown closer to processing facilities. Although estimated ethanol yields of alfalfa averaged one-fourth lower than for corn, the net energy gain in delivered biomass was 25X for alfalfa, but only 8X for corn grain and 11X for corn grain plus stover. Mapping the expected yields of potential feedstock crops in a fuelshed can help planners decide which crops to select and where to concentrate the feedstock contracts to achieve the multiple goals of alternative fuel production and other environmental benefits.