Abstract
Willow biomass is found to be an excellent fuel for farm-based power generation by utilizing an advanced gasifier system that uses high-temperature preheated air as the gasification medium. The gasifier's product fuel gas can be used in microturbines to generate electricity or used for other farm energy needs. The gasifier performance under various operating conditions is estimated using a previously developed gasifier model. The net gasification efficiency is about 85 percent under nominal operating conditions. The capital cost of a small, farm-based power system is estimated to be about $2,800/kW. Using the latest published information on willow biomass production cost, the cost of electricity is estimated to be 9 cents/kWh and is reduced to 7.2 cents/kWh when willow is grown on Conservation Reserve land. The costs associated with harvesting, handling, and transporting the willow biomass account for 40 to 50 percent of the annual operating cost. Results also show that co-gasification of willow with low-cost wastes, such as dairy farm animal wastes, can reduce fuel cost, increase the overall fuel availability and help work around problems resulting from seasonal availability of biomass crops. Co-gasification of willow biomass with manure waste also benefits the dairy industry by providing an economical way to dispose of farm wastes and manage nutrient flows.