Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/3/2011
Publication Date: 11/16/2011
Citation: Muck, R.E. 2011. Potential of energy production from conserved forages. Proceedings of II International Symposium on Forage Quality and Conservation. p. 7-24.
Technical Abstract: Forages have a potential role in meeting the demand for energy. Perennial forages are attractive for various reasons. One, both the monetary and energy cost of planting is spread over many years. Two, we already have the equipment for harvesting, storing and transporting this source of biomass. Three, legume forages or legume-grass mixtures need no or little nitrogen fertilizer, a major energy input for most crops. Four, forages can be grown on marginal agricultural lands and so do not compete with land that could be best utilized for direct human food production. Finally, perennial forages stabilize and enhance soil systems, minimizing erosion and building up soil organic matter, sequestering carbon. A wide variety of forage species are being investigated, but most are C4 grasses. While standard harvesting equipment can be used, there are opportunities for other alternatives such as leaf-stem or liquid-solid separation to the increase the value of the products from forages. Traditional hay and silage storage systems can be employed, but ensiling provides the opportunity for pretreatment. The technologies for utilizing forage for energy production that are closest to adoption are ethanol production and anaerobic digestion to produce methane. Pyrolysis, combustion and butanol production are more distant possibilities for energy generation. Beyond the technical challenges, energy generation from forages must fit into a sustainable system that does not compete with the food system and provides farmers with a reasonable profit.