Effect of Harvesting Time and Moisture Content on Energy Consumption of Compressing Switchgrass

Abstract

As a dedicated energy crop, switchgrass may be harvested in fall or early spring depending on weather conditions, field capacities of harvesting machines, storage capacities, field management and availability of machine operators. To reduce storage space demand and increase transportation efficiency, harvested switchgrass should be densified. This research was conducted to examine energy consumption of compressing switchgrass collected from various harvesting seasons. Results indicated that the switchgrass harvested in the spring required the maximum energy consumption to process due to its dry and brittle nature. Conversely, the switchgrass harvested in the fall required less energy to compress due to its higher moisture content and associated reduction in resistive forces. For the same moisture content, fall harvested switchgrass would consume less energy to compress compared to spring harvested due to changes in properties of switchgrass over the winter.