Uncertainty in Life Cycle Greenhouse Gas Emissions from United States Coal

Abstract

Coal is an abundant energy resource, consumed in the United States chiefly by the power generation sector. Due to potential energy security benefits, it has also been considered as an alternate source for gasoline and diesel production. Life cycle assessment (LCA) studies have previously estimated the greenhouse gas emissions associated with coal combustion as well as upstream activities such as mining and transport, to compare its environmental impact with other fuels. Until recent years, LCA studies predominantly ignored the uncertainty and variability inherent in life cycle assessment. More recent work has estimated the uncertainty in the life cycle inventories of fossil fuels, but the use of these uncertainty ranges to model system-wide impacts has been limited. As shown by previous studies, uncertainty often affects the conclusions of comparative life cycle assessments, especially when differences in average environmental impacts between two competing fuels/products are small. This study builds upon ...