Environmental challenges in electrification: Traffic-induced non-exhaust PM2.5 emissions in Cangzhou, China

Non-exhaust PM2.5 emissions are often overlooked despite their increasingly significant contribution. Including non-exhaust emissions to establish a complete road emissions inventory is critical for formulating effective control strategies and reducing health risks especially during the fleet electrification process. This study developed a PM2.5 emission estimation framework incorporating exhaust and non-exhaust sources, validated by roadside PM2.5 concentrations from a mobile cruise sensing system in Cangzhou, China. The results found that traffic-related PM2.5 concentrations contributing to roadside environments exhibit hourly variations, with an average proportion of 44.05 %. Analysis of peak-hour PM2.5 emissions revealed the non-exhaust sources dominate (91.38 %). Under scenarios with 35 %, 50 %, 75 %, and 100 % electrification rates, PM2.5 emissions will decrease by 6.96 %, 11.01 %, 17.77 %, and 24.53 %, respectively, compared to the baseline. This study highlights that fleet electrification will not completely eliminate PM2.5 emissions, and helps identify priorities and develop targeted emission control policies for medium-sized populous cities in developing countries.