Decarbonizing urban passenger transportation: Policy effectiveness and interactions

The urban passenger transportation plays a pivotal role in achieving ambitious climate targets. Exploring its opportunities for decarbonization requires a comprehensive understanding of the impacts of different policy designs. This study develops an integrated model for simulating the effectiveness and interactions of various policy designs aimed at decarbonizing urban passenger transportation. It distinguishes itself from previous studies by considering a broad range of criteria, including mitigation effectiveness, cost effectiveness, and transition effectiveness. It also assesses the overall performance of various policy options based on these effectiveness criteria. In an urban case study, we have identified the complementary nature of the majority of policy mixes and also revealed conflicting effects when implementing a supplementary policy, such as carbon tax and fuel economy regulation. The concurrent implementation of multiple policies can yield synergistic effects or trade-offs, with the former being widely acknowledged in the context of energy transition, while the latter is more commonly observed in relation to emissions reductions and cost savings. This study also reveals a trade-off effect across various effectiveness criteria, underscoring the significance of formulating well-balanced policy packages to promote sustainable urban passenger transport.