Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only
Publication Acceptance Date: 9/12/2006
Publication Date: 10/14/2006
Citation: Wilson, J.P., McAloon, A.J., Yee, W.C., McKinney, J., Wang, D., Bean, S.R. 2006. Biological and Economic Feasibility of Pearl Millet as a Feedstock for Ethanol Production. 6th New Crops Symposium, Association for the Advancement of Industrial Crops. San Diego, CA, Oct. 14-18, 2006. p. 47. Interpretive Summary: not required
Technical Abstract: Development of the ethanol industry in the southeastern U.S. is limited by the level of corn produced in the region. Additional feedstocks are needed to supplement locally-grown corn for an ethanol plant to be viable. These studies were conducted to evaluate the biological and economic feasibility of using pearl millet as a supplemental feedstock in a dry-grind ethanol production process. For ethanol production, pearl millet grain was subjected to different grinding processes. The rate of the fermentation process for the pearl millet treatments and a corn control were measured, and the resulting composition of the distiller’s dry grains with solubles (DDGS) was determined. A process and cost analysis was used to assess the economic feasibility of using pearl millet as a feedstock. Expected yield of ethanol and DDGS was calculated based upon grain composition. Other variables in the model include the cost of feedstock, sizing of equipment, utility consumption, operating costs, capital costs, and revenue from products and coproducts. Fermentation studies demonstrated that pearl millet can be converted to fuel ethanol using a conventional corn-to-ethanol process without significant modifications. Final fermentation efficiency was approximately 4% less than corn, but pearl millet fermented more quickly and reached 85% fermentation approximately 12 hours earlier than the corn treatment. The DDGS from pearl millet was higher in protein and fat, and lower in fiber compared to corn DDGS. The process and cost analysis indicated that the higher protein content of pearl millet would result in a 13% greater DDGS coproduct income compared to corn. Within the limitations of this preliminary analysis, results suggest that even with a 10% premium on the cost of pearl millet, the net cost of ethanol production is $0.06 per gallon less than production using corn.