Impact of battery electric vehicle penetration and corresponding changes in upstream processes on summer O3 concentrations in Japan

Abstract

A regional meteorology-chemistry model was used to assess the effects of passenger car conversion to battery electric vehicles (BEV) on summer O3 concentrations in Kanto (Japan's most populous region). Four sensitivity experiments were conducted on different on-road and upstream (power plant and gas station) emission conditions. Daytime 8-h maximum O3 decreased by 3 ppb (5%) and 4 ppb (5%) in urban and inland suburbs, respectively. O3 levels decreased even in urban (VOC-limited regions) because exhaust and evaporative VOC emissions from vehicle and gas stations were reduced effectively (especially alkenes from gasoline evaporation; highly reactive in O3 formation). In the suburbs (NOx-limited regions), reduction of exhaust NOx by BEV shifting was significant, but in urban, even only evaporation measures induced almost the same O3 reduction effect as BEV shifting. The additional emissions from thermal power plants due to BEV night charging contributed little to the next day's daytime O3 on a monthly average basis. However, on some days, pollutants were stored in the upper part of the stable nighttime boundary layer and could affect the surface O3 as the next day's mixed layer development. Depending on the O3 sensitivity regime (NOx-or VOC-limited), additional NOx plumes from rural (urban) power plants tended to increase (decrease) the next day's O3. However, the distribution of the regime changes temporally and spatially. The H2O2/HNO3 ratio was discovered to be a clear indicator for distinguishing regime boundaries and was effective in predicting positive or negative O3 sensitivity to the additional emissions from power plants.

Potential Impacts of Energy and Vehicle Transformation Through 2050 on Oxidative Stress‐Inducing PM2.5 Metals Concentration in Japan

“…Also, Table 2 shows the assumptions that were changed and unchanged from the BESE experiment. Our previous study (Kayaba & Kajino, 2023), which estimated the impact of the BEV shift of all passenger vehicles on surface O 3 concentration, did not consider the future scenarios of changes in vehicle type mix or power supply mix. However, in this study, we developed detailed future scenarios based on the Japanese government targets.…”

Potential Impacts of Energy and Vehicle Transformation through 2050 on the Atmospheric Environment of Japan: focus on PM2.5 Metals and Aerosol Acidity inducing Respiratory Inflammation

“…The emissions for each sensitivity experiment were determined by scaling the base experiment by the coefficients shown in Table 1. Our previous study (Kayaba and Kajino, 2022), which estimated the impact of the BEV shift of all passenger vehicles on surface O 3 concentration, did not consider scenarios of changes in vehicle type mix or power supply mix over time. However, we developed detailed future scenarios based on the aims of the Japanese government in this study.…”