Exposure to air pollution claimed the lives of about seven million people worldwide in 2010, largely from combustion of solid biomass fuels. Bioenergy is an alternative renewable source which can mitigate a climate change. Little is known about the human health and ecosystem effects of bioenergy, mainly in the electricity sector. This research applied a life cycle assessment approach to examine the human health and ecosystem effects of four bioenergy pathways: direct combustion of wood biomass, direct combustion of forest residue, direct combustion of pellets, and biomass integrated gasification and combined cycle (BIGCC). All pathways showed some variability of impacts; therefore, no single bioenergy pathway was the best absolute option. With the exception of the slightly higher human health impact, BIGCC has the least impact for all impact categories. However, all bioenergy systems implied lower ecosystem impact but higher human health impact as compared to climate change impact. Electricity generation from wood-biomass would improve the environmental sustainability of Alberta's electricity grid system because it reduces the human health and ecosystem impacts, as compared to the existing electricity production mix of the province. (C) 2017 Elsevier Ltd. All rights reserved.