Parametric study of machinery management relationships on forage equipment

Model simulations for bioenergy field planning need to utilize equipment capacity relationship operating under field conditions. These assumptions have a direct bearing on the estimates of the machine capacity, the number pieces of equipment and therefore cost to fulfill these demands during the harvest window. Typically two major issues in these models have limited understanding, the available time which the operation are required to complete (often called probability of workdays, pwd) and the capacity of forage equipment as impacted by yield. Plus, most current forage equipment has limited experiences (as well as published results) from operating in high-yielding conditions. Simulation of annual yield estimates which corresponds to the weather events are often integrated into these models to demonstrate year-to-year effects and increase potential from genetic modified energy crops. As an example the modified ISBAL model is applied to harvesting stover, straw, and switchgrass with yield ranging from 2 to 7 dry-Mg ha^-1 for straw and stover and 5 to 50 dry-Mg ha^-1 for switchgrass. Forage equipment performance are demonstrated and the impact of throughput restriction and baler wrap/eject process are documented. The impact of wrap/eject was a 50% reduction in capacity. After the maximum throughput is achieved, the cost of the round bale operation ($3.23 Mg^-1) is double that of the square baler operation ($1.63 Mg^-1). The round baler capacity is more than 50% less (32.7 Mg h^-1 compared to 71.0 Mg h^-1) than the square baler.