Evaluation of mitigation effects on air pollutants for electric scooters in Taiwan with the energy flow analysis and system dynamics approach

This research establishes a localized dynamic system model to explore changes of air pollution emission in the transition of electric scooters (ES) considering energy transformation. The calculation of emission factors (EF) of criteria air pollutants and greenhouse gases for Heavy-duty Gasoline-powered Scooters (GSH) and Heavy-duty ES (ESH) is performed with energy flow analysis. Compared with the GSH, the EF of TSP, NOx, VOCs, and CO₂e for ESH reduce by, respectively, 14.8%, 97.4%, 100%, and 76.8% per kilometer travelled in 2016; although the SOx EF for ESH is 2.4 times higher than that for GSH, the increment is down to 22.2% in 2025. If the SOx emissions intensity of electricity reduce to 100 mg/kWh, the SOx EF for ESH will be lower than that for GSH. System dynamics and energy flow analysis can provide effective analysis about mitigation scenarios and these findings are helpful to local authorities for air quality management.