Localised evaporative emission inventory of gasoline vehicle volatile organic compounds (VOCs) in China: Insights into regional variations and driving behaviours

Evaporative emission from gasoline vehicles is a major source of volatile organic compounds (VOCs) in China. This study developed a localised evaporative emission model that incorporated key factors, such as fuel vapour pressure, temperature variations, fuel tank volume, carbon canister size, mileage, and parking behaviour. Drawing from the American MOVES and European COPERT models and combining with the real situation in China, the study created an emission inventory categorised by vehicle types, emission standards, emission processes, and regions. It also estimated changes in evaporative emissions under the influence of climate change. The results revealed that, in 2020, evaporative emissions from gasoline vehicles in China reached 517,000 tonnes, with diurnal and hot soak emissions contributing the largest share (63 %). By 2025, these emissions are projected to increase to 602,000 tonnes before declining to 408,000 tonnes by 2030. Furthermore, the characteristics of evaporative emissions vary significantly by region and driving behaviour, with particularly high emissions observed in Guangdong and other provinces. Therefore, future air pollution prevention and control strategies in China should consider these regional and behavioural variations. From the perspective of the classification of this study, targeting evaporative emissions in 13 key provinces can effectively control 66 % of the total VOCs emissions of the nation.