Publication Detail
|
UCD-ITS-RR-13-40 Research Report Alumni Theses and Dissertations Download PDF |
Suggested Citation:
Murphy, Colin (2013) Modeling the Environmental Impacts of Cellulosic Biofuel Production in Life Cycle and Spatial Frameworks. Institute of Transportation Studies, University of California, Davis, Research Report UCD-ITS-RR-13-40
Biofuels may be able to reduce greenhouse gas (GHG) emissions from the transportation sector, expand domestic energy production and spur rural economic development. Lignocellulosic biofuels are of particular interest because they can use waste or residual biomass as feedstock, or feedstock grown on marginal cropland. Research on lignocellulosic biofuel production pathways has revealed risks of environmental impacts, such as land transformation, loss of soil carbon and air pollutant emission.
This dissertation examines areas of uncertainty regarding the environmental impacts of biofuel production systems through four research studies, three which focus on the environmental impacts of biofuels within a life-cycle analysis framework, and the fourth which uses large-scale spatially explicit technoeconomic modeling to evaluate interactions between biofuel production systems and air-quality policy. These will help inform decisions on how best to minimize environmental impacts, particularly a biofuels’ GHG balance, as large-scale biofuel production expands.
Results show that life-cycle environmental impacts of biofuels are often dominated by the feedstock production phase. Soil organic carbon changes are among the most important and most uncertain of all processes from biofuel production. In corn stover production systems, sustained removal of biomass from a field reduces the amount of carbon sequestered in soil, which can dominate other GHG emissions. This decrease can exceed one tonne of CO2 equivalent per hectare of corn from which stover is removed. Fertilizer production and conversion facility energy demands are also major sources of environmental impact. Cellulosic biofuels have the potential to reduce GHG emission, when displacing conventional fuels, but substantial uncertainty remains within the production system.Some chapters of this dissertation have been published elsewhere:
Ph.D. Dissertation