Light-duty plug-in electric vehicle adoption: County-level emissions benefits using consumption-based emissions intensities

The electrification of light-duty vehicles (LDVs) is essential for decarbonizing the transportation sector in the United States. Both federal and state governments have begun promoting and incentivizing the adoption of plug-in electric vehicle (PEV) (battery electric vehicles (BEV) and plug-in hybrid electric vehicles (PHEV)) to reduce LDV greenhouse gas (GHG) emissions greatly. However, there remains a critical need for a robust methodology to accurately quantify the distributed emissions impacts of PEV adoption at a granular regional level. Additionally, the role of electricity traded across electrical grids in regional GHG mitigation efforts often goes unrecognized. This study addresses these gaps by developing a top-down approach for assessing county-level emissions benefits arising from PEV adoption while accounting for upstream emissions due to electricity flow across regions. Our findings underscore the significant influence of regional variations in future PEV adoption rates and vehicle usage patterns on emissions reduction potential. Nevertheless, these benefits can be tempered by local emission intensities associated with electricity generation. Importantly, our study reaffirms the necessity of considering electricity flow dynamics across grids in estimating local GHG mitigation outcomes.