Harvesting system design and performance

Bioenergy crop harvesting is a critical operation affecting bioenergy supply logistics. It includes the tasks of cutting, gathering, and conditioning of bioenergy crop so as to make it suitable for subsequent operations. Harvesting represents a significant amount of biomass cost at the farm gate. This chapter reviews and discusses harvesting technologies for four major bioenergy crop alternatives: energy grasses (Miscanthus and switchgrass), short rotation woody crops (willow, poplar), green crops (energy cane, sorghum, sugar cane), and agricultural crop residue (corn stover, orchard residue). It describes crop characteristics important for designing harvesting machinery and different machinery options used for harvesting promising bioenergy crops. It also describes the functional processes involved in a crop-specific harvesting operation and compares their operational principles. The harvesting machinery performance data are compiled to facilitate equipment selection. Finally, this chapter discusses observed limitations of the machinery evaluated and future challenges to be addressed.