Vehicle emission inventories projection based on dynamic emission factors: A case study of Hangzhou, China

To project vehicle emission inventories more accurately in China, dynamic vehicle emission factors have been developed considering several factors such as regulated emission limits, regulated fuel economy, vehicle deterioration of emission factors, and fuel economy deterioration. This study has also developed a method to estimate fuel economy based on fuel economy claimed by manufacturers, a ratio of real road fuel economy on road/fuel economy claimed by manufacturers, vehicle deterioration rate, vehicle stocks, and fuel economy regulation in China. The emission inventories of CO, VOCs, NOx, PM10, and CO2 from vehicle fleets in Hangzhou, China during 2004–2030 are projected using above two methods. The projected results show that regulated vehicle emission limits of National I and II standard of China are not effective to reduce the emission factors of vehicles except motorcycles, and only National III and National IV of Vehicles Emission Limits can apparently reduce overall emission factors of all type vehicles with both gasoline and diesel. The results also show that emission factors will continue to decrease after 2010. Up to 2030, the total emission inventories of CO, VOCs, NOx, and PM10 will increase by 467.52%, 61.44%, 8.31%, and 78.35%, respectively. However, emission inventory of CO2 will grow continuously to 2030 with 770.54% growth rate.