6. Perennial grasses as a viable biofuel source in eastern Ontario

Abstract

Climate change and energy security issues have made renewable energy production an important global issue. Bioenergy crops may be able to provide a large amount of the world’s energy needs; therefore it is important to determine their potential for viable and sustainable use. Perennial grasses are an ideal bioenergy crop because they grow quickly across a wide range of climatic and soil conditions. Nitrogen based fertilizers are often used to increase productivity but overuse can lead to excessive nitrous oxide (N2O) emissions, a greenhouse gas (GHG) 300 times more potent that carbon dioxide (CO2). Fertilizing becomes counterproductive when N2O emissions outweigh the benefit gained from reduction in CO2 emissions.
 Three perennial grass species (Panicumr virgatum, Schizachyrium scoparium and Andropogon gerardii) were grown in collaboration with Lafarge Cement in Bath, Ontario. Each species was grown under three different fertilization regimes: 0, 50 and 150 lbs/acre of nitrogen as urea. Results of one study indicate that low levels of fertilizer addition enhance the GHG benefits of the grass, but results from another site suggest no benefit. 
 Our current research is exploring the importance of various soil processes to production of GHG’s in these perennial grass bioenergy systems, and whether the grasses alter soil conditions to favor certain soil processes. The information gained will help to further predict the feasibility of using nitrogen fertilizers to enhance production in these bioenergy systems and the overall viability of bioenergy crops for cement manufacturing and other applications.