ABSTRACT
544With growing concerns about climate change and energy demands, the need for alternatives to fossil fuels persists. Bioenergy has the potential to offset greenhouse gas (GHG) emissions from fossil fuel, but requires expansion, intensification, or repurposing of agricultural land. Complexities associated with land use change have fueled controversy around bioenergy, even while land development and environmental impacts for other energy industries are poorly described. Agriculture, bioenergy, and fossil fuels might instead be viewed as part of a multiuse landscape to promote optimized production of all resources and decrease environmental impacts of energy and agricultural sectors of the economy. Optimization requires complimentary analyses of bioenergy, agriculture and fossil fuel production systems, but currently there is a lack of standardization in the life-cycle analyzes (LCAs) of these production systems. In this chapter, we compare the GHG emissions estimated in published LCAs for each of these resources, analyzing differences in the system boundaries and associated effects of life-cycle GHG emissions. Systems for handling wastes and recycling or disposing chemical byproducts are also compared. System boundaries differ across production systems, with assessments of bioenergy consistently using larger system boundaries than assessments of fossil fuel energy and other agriculture. Differing system boundaries limit the ability to make direct comparisons of the environmental impacts of resource production systems. Standardized analyses of resource production systems would better inform policies that can incentivize efficient production of all resources, reduce wastes, and increase the opportunities for climate change mitigation.
