Economic and Environmental Sustainability of Small Nebraska Greenhouse Systems

Abstract

<abstract> <bold>Abstract.</bold> The purpose of this paper was to increase the profitability in Nebraska greenhouses by using biomass fuels for heating instead of propane. Several different fuels were tested, including whole shelled corn, dry distiller’s grains, pelletized wood pellets, and blends for each biomass, with the primary focus on whole shelled corn. Bomb calorimetry tests were performed on biomass fuels and their respective ash contents. Several furnace and heat exchanger efficiency tests were performed, with a cost effectiveness analysis for each fuel type. Emissions data was also acquired for each fuel that included carbon monoxide, carbon dioxide, nitrous oxides, sulfuric oxides, and particulate matter. The study used a biomass furnace donated to a greenhouse at Firth, Nebraska and an existing propane furnace. Although the biomass furnace generally had a lower efficiency than the 81 percent advertised for the propane furnace, the biomass fuels were more cost effective than propane. The biomass efficiencies typically ranged from 50 to 80 percent. Over a four year period (2008-2011), the cost savings of biomass fuels ranged from 30 to 60 percent and totaled a little over $15,000. Overall, the use of biomass furnace showed considerable potential when utilized for heating in Nebraska greenhouses.