Environmental impact assessment of biomass supported electricity generation for sustainable rural energy systems - A case study of Grenada County, Mississippi, USA

Abstract

Fossil fuels have been the major source of electricity supply in the United States of America (USA) for many decades. While a significant shift has occurred from coal-dominated supply to natural gas and renewable source based supplies in recent decades, there is still large potential to improve biomass supported electricity contribution in rural communities, which depend majorly on forest-related activities. Wood waste, an underutilized renewable resource, has the potential for electricity generation in rural areas to reduce the contribution of electricity generated from fossil fuels and assist in greenhouse gas savings. In this study, a life cycle assessment approach was used to estimate the emissions of electricity generated by wood residues in a rural community (Grenada County, Mississippi (MS), USA) and compared with those emissions from the recent electricity mix (2018), a previous electricity mix (2010) supply, along with natural gas (NG) and coal (Bituminous Coal, BC) based electricity generation options. A significant reduction (85.9–94.6%) in global warming impact was observed when compared with BC, NG and grid supplied electricity for years 2010 and 2018. When compared to the current electricity mix at the grid (2018), acidification, eutrophication, respiratory effects and smog formation showed higher emissions ranging from 30.8% to 72.4%. The sensitivity analysis showed an improvement in emissions savings with increased biomass to power conversion efficiency (40%), lower moisture content of the biomass (0%, bone dry biomass), and reduced transportation distance (35 km). This study showed an improvement in the electricity mix supplied to Grenada county, MS, which implies sustainable development opportunities for promoting energy security in rural communities with forest-based industries.