Switchgrass as an Alternate Feedstock for Power Generation: Integrated Environmental, Energy, and Economic Life-Cycle Analysis

Biomass conversion into forms of energy is receiving current attention because of environmental, energy supply and agricultural concerns. This objective of this paper is to report on the environmental, energy, economic, and technological aspects of using switchgrass (panicum virgatum) as a replacement for coal in power generation. To examine the effects of such a substitution, an environmental biocomplexity approach is used to analyze the interactions of agricultural, technological, economic, and environmental factors. In particular, lifecycle analysis (LCA) is used. The three-dimensional economic, energy and environmental analysis shows that the most effective technologies for switchgrass preparation are harvesting loose switchgrass for hauling and chopping and then transporting after compression into modules. The greenhouse gas (GHG) mitigation during co-firing of switchgrass with coal is found to be greater per ton of switchgrass used than the GHG mitigation for switchgrass fired alone with the GHG effects of 58.1 g CO2-Eq /kWhr for 5% switchgrass co-fired with coal and 90.5 g CO2-Eq /kWhr for switchgrass fired alone. This paper discusses the sensitivity of this finding to varied co-firing ratios, coal prices, hauling distances, and per acre yields.