Potential for Electric Vehicle Adoption to Mitigate Extreme Air Quality Events in China.

Electric vehicle (EV) adoption promises potential air pollutant and greenhouse gas (GHG) reduction co‐benefits. As such, China has aggressively incentivized EV adoption, however much remains unknown with regard to EVs' mitigation potential, including optimal vehicle type prioritization, power generation contingencies, effects of Clean Air regulations, and the ability of EVs to reduce acute impacts of extreme air quality events. Here, we present a suite of scenarios with a chemistry transport model that assess the potential co‐benefits of EVs during an extreme winter air quality event. We find that regardless of power generation source, heavy‐duty vehicle (HDV) electrification consistently improves air quality in terms of NO2 and fine particulate matter (PM2.5), potentially avoiding 562 deaths due to acute pollutant exposure during the infamous January 2013 pollution episode (∼1% of total premature mortality). However, HDV electrification does not reduce GHG emissions without enhanced emission‐free electricity generation. In contrast, due to differing emission profiles, light‐duty vehicle (LDV) electrification in China consistently reduces GHG emissions (∼2 Mt CO2), but results in fewer air quality and human health improvements (145 avoided deaths). The calculated economic impacts for human health endpoints and CO2 reductions for LDV electrification are nearly double those of HDV electrification in present‐day (155M vs. 87M US$), but are within ∼25% when enhanced emission‐free generation is used to power them. Overall, we find only a modest benefit for EVs to ameliorate severe wintertime pollution events, and that continued emission reductions in the power generation sector will have the greatest human health and economic benefits. Plain Language Summary: Electric vehicles (EVs) offer potential air quality and climate change co‐benefits, but due to varying power generation and vehicle types, and because air pollution chemistry is nonlinear, it is not clear to what extent EVs could provide mediation, especially during extreme air pollution episodes. China is both rapidly adopting EVs and frequently experiences poor air quality. We use an air quality model that simulates the complex interplay between weather and air quality to examine the potential co‐benefits of EVs in China during a historical pollution episode. We simulate both light‐ and heavy‐duty vehicle adoption to show their individual benefits, and demonstrate the need for low‐emission electricity generation to maximize co‐benefits. Overall, we find that heavy‐duty fleet electrification consistently improves air quality and reduces mortality, but offers little climate change benefits without enhanced emission‐free electricity generation. Light‐duty vehicles, however, offer large climate change benefits but few air quality improvements, highlighting the need for cross‐modal adoption strategies. Key Points: Heavy‐duty vehicle electrification in China consistently improves air quality regardless of power generation sourceLight‐duty vehicle electrification offers less air quality benefits but consistently reduces total CO2 emissionsPower sector emission reductions are central to achieving co‐benefits from electric vehicles [ABSTRACT FROM AUTHOR]