Advancing Life Cycle Comparisons of Future Alternative Light-duty Vehicles

The overall objective of this thesis is to systematically compare the life cycle energy use, air emissions and costs of future alternative light-duty vehicles in a more robust manner than is done in the literature. Models are developed using GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation), Autonomie vehicle simulation software, Vehicle Attribute Model, Air Pollution Emission Experiments and Policy (APEEP) analysis model, and Crystal Ball (Monte Carlo analysis). Four questions are investigated: • Should the transportation sector use ethanol or bio-electricity? Life cycle assessment results indicate that neither has a clear advantage in terms of greenhouse gas (GHG) emissions or energy use. This finding is in contrast to those in the literature that favor the use of bio-electricity because this thesis develops pathways with comparable vehicle characteristics. • Do plug-in electric vehicles provide incremental life cycle air pollutant impact benefits over internal combustion engine vehicles using the same primary energy source? The results based on natural gas-derived fuels show that battery electric vehicles (BEV) may not provide benefits, in terms of climate change and health impacts, over hybrid electric vehicles (HEV). This can be attributed to the many sources of uncertainty and stringent tailpipe emissions regulations. • How can vehicles be designed to meet future CAFE (Corporate Average Fuel Economy) standards? Case study results for a reference vehicle show that the 66% increase in fuel economy targets between model years 2012 to 2025 can be met with a 10% vehicle price increase (lightweight HEV powertrain), 31% increase in 0-96 km/h acceleration time (smaller engine), 17% interior volume decrease (smaller body), or 94% driving range decrease (BEV powertrain), while other attributes are maintained. • How might CAFE standards affect the ability for non-petroleum vehicles to mitigate GHG emissions by displacing petroleum vehicles? Life cycle costing results indicate that there is a financial incentive for automakers to produce CNG vehicles that could emit higher well-to-wheel GHG emissions on a per kilometer basis than gasoline vehicles. This is permitted by CAFE standards because non-petroleum fuel incentives allow vehicles using CNG to be less efficient, and thus potentially more affordable, than those using gasoline.Ph.D