Modeling personal vehicle energy consumption to assess the potential for electrification and decarbonization

Abstract

This thesis develops a new model of the energy requirements of personal vehicle travel and uses it to evaluate tools to decarbonize the transport sector. Energy use and carbon emissions from transportation are spread across millions of miles of roadways and hundreds of millions of travelers. This diversity of travel patterns makes it challenging to catalogue and predict those quantities and difficult to characterize the mechanisms that drive them. However, a better understanding of transport energy use patterns is needed to find options for reducing personal vehicle energy requirements and greenhouse gas emissions. Existing research on transportation and climate policy often represents energy use in a fundamentally simplified manner. Some research does not account for the effect of usage patterns on technology performance, missing variation in technology impacts across context of use.

Other research informs technology modeling with a simplified picture of travel patterns, missing contexts in which technologies will be used. The research in this thesis adds new insight by assessing technology performance based on a comprehensive picture of travel patterns. This better captures both how travel patterns determine technology performance and how technology performance constrains achievable transformations to the transport sector. It combines high-resolution driving data with comprehensive travel patterns from household travel surveys or a transport network simulation, integrating data at multiple scales to avoid simplifications that mask relationships between technology use, technology performance, and systemwide carbon intensity. The central finding of this thesis is that retaining heterogeneity in travel behavior and technology performance allows us to better understand barriers to and strategies for transport decarbonization that will be missed with simpler methods.

Specifically, this thesis addresses electric vehicle range limitations, finding that they provide a constraint on transport electrification that is relatively limited and consistent across locations. This research also reveals interactions between electric vehicle charging and the electricity grid and uncovers how to better align electricity demand and supply under high solar photovoltaics penetration. This understanding will help inform targeted technological development and policies as well as help identify risks and unintended consequences in a transition to a low-carbon transportation system.