ARS | Publication request: Development of Switchgrass Into a Biomass Energy Crop

Submitted to: University of Minnesota Special Publication
Publication Type: Proceedings/Symposium
Publication Acceptance Date: May 1, 2008
Publication Date: August 19, 2008
Publisher's URL: http://www.cinram.umn.edu/srwc/
Citation: Vogel, K.P., Mitchell, R., Sarath, G. 2008. Development of Switchgrass Into a Biomass Energy Crop. p. 64. In: R.S. Zalesny, Jr., R. Mitchell, and J. Richardson (eds.). Proceedings of the Short Rotation Crops International Conference, Bloomington, Minnesota, August 19-21. http://www.cinram.umn.edu/srwc/

Technical Abstract: Switchgrass (Panicum virgatum L.) is a North American prairie grass that is being developed into a biomass energy crop in the USA and other countries. Research on switchgrass as a pasture and forage crop was initiated in the mid-1930's in an U.S. Department of Agriculture and University of Nebraska cooperative program. In 1990, work also was initiated to develop switchgrass into a biomass energy crop which included both breeding and management research. Critical questions for a biomass bioenergy production system include: What are the economics? Is energy from biomass net energy positive? Is production system information available and verified? Is the system sustainable? To address these questions, ten farmers in the mid-continental USA were contracted to grow switchgrass in 6-8 ha fields for a five year period and manage it as a biomass energy crop using available cultivars and management practices during the period 2000-2005. Results indicate that during this period switchgrass biomass feedstock could have been produced in this region at a cost of about $50 Mg-1 at the farm gate, which translates to about $0.13 per liter of ethanol. Net energy yield on the established switchgrass fields was 60 GJ ha-1 y-1. Switchgrass in these farmer trials produced 540% more renewable energy than nonrenewable energy consumed. These baseline studies represents the technology that was available for switchgrass in 2000 and 2001 when the fields were planted but clearly demonstrate that for switchgrass a full array of production system technology is available for its use as a biomass energy crop. Improved genetics and agronomics will further enhance energy sustainability and biofuel yield of switchgrass. Carbon sequestration research is still in progress, but the initial results are very encouraging. Technology has been developed to rotate from switchgrass to crops including maize and soybeans and back to switchgrass without plowing.