State-level emission trends from battery electric vehicle adoption in the U.S.

This study evaluates the potential transformation of the U.S. transportation emissions landscape through a complete transition from internal combustion engine vehicles to battery electric vehicles, focusing on both current and future emission scenarios. Present day emissions were analyzed using data from the National Household Travel Survey, incorporating vehicle specific attributes such as model year, fuel economy, and household miles traveled at the state level. Future projections assume full adoption of battery electric vehicles (BEVs) under three electricity grid scenarios: the Mid-Case (current policy trajectory), the Mid-Case with 95% Decarbonization, and the Low Renewable Energy Cost Case. The results indicate that states with higher emissions from internal combustion engine vehicles (ICEVs) often correspond to higher household travel demand, while BEVs consistently demonstrate lower emissions particularly when powered by cleaner energy sources. However, the benefits of this transition vary significantly across states due to differences in energy policies, grid mix, the type of vehicles being replaced, and travel behavior. Under the current grid mix, state-level emissions reductions range from 39% to 98.5%, but gains in larger, clean-energy states may be offset by fossil fuel-dependent smaller states. Notably, even under future grid scenarios, states like Pennsylvania and Michigan continue to contribute significantly to U.S. transportation emissions despite having smaller populations than California due to slower decarbonization of their electricity sectors. These findings underscore the need for coordinated policies that not only incentivize BEV adoption but also promote renewable energy integration and encourage behavioral changes in high-emission states. Targeted action by electricity providers, particularly in major contributing regions, is critical to achieving substantial and equitable emission reductions nationwide.