Study on the Operational and Low-Carbon Efficiency of URT Based on Super-Efficiency SBM-GML Model

To evaluate the operation and low-carbon efficiency of urban rail transit (URT), a URT efficiency evaluation model was constructed based on the non-directional Super-efficiency SBM-GML method considering the undesired output. The quantitative analysis of the URT efficiency and its dynamic changes in 32 cities from 2019 to 2021 was conducted. The results show the following: (1) The URT efficiency value in cities at the initial development stage and the mature stage is higher than at the growth stage, but the effectiveness of URT is unstable in the initial development stage, and there are significant efficiency differences among cities. (2) In 2020, 93.7% of cities experienced a decline in URT efficiency, while in 2021, 68.8% of cities improved compared to 2020. (3) The operation of URT in inefficient cities was characterized by wasteful use of transportation resources, insufficient passenger attraction, and high carbon emissions. There is a great potential for improvement in energy-saving and emissions reduction.