System dynamics based influencing factors of carbon emission reduction for highway transportation

ObjectiveThis study investigates the influence of different influencing factors on carbon emission reduction for highway transportation in Zhejiang Province, providing references and suggestions for relevant departments in Zhejiang Province.MethodThe system dynamics model of carbon emission reduction for highway transportation was established in Zhejiang Province based on real data. The proportion of vehicles using various fuels with various traffic modes, the fuel consumption per hundred kilometers, and the annual mileage per vehicle were selected as influencing factors by sorting out causal relations among various variables in model. The scenario simulations were carried out based on the situation in 2021 as the baseline scenario.ResultThe carbon emission reduction effect obtained by optimizing vehicle energy intensity is the best; the effect obtained by optimizing transportation structure is the weakest; while the effect obtained by optimizing vehicle energy structure falls somewhere between the two. Reducing the proportion of non-clean energy vehicles for highway freight transportation is an influencing factor that has good carbon emission reduction effect and easy policy promotion. Reducing the average annual mileage of a single vehicle for highway freight transportation is an influencing factor with good carbon emission reduction effect but difficult policy promotion. Reducing the fuel consumption per hundred kilometers for non-clean energy vehicles in highway freight transportation is an influencing factor with good carbon emission reduction effect but very difficult policy promotion.ConclusionThe suggestions for carbon reduction in highway transportation are proposed from the aspects of accelerating elimination of old diesel trucks, promoting clean energy vehicles for highway transportation, developing large-scale and specialized highway transportation equipment, and promoting multimodal transport.