An assessment model of eco-efficiency for container terminals within a port

Greenhouse gas emissions, such as carbon dioxide (CO2) from container terminal (CT) operations, generate an adverse impact on the ecological environment in ports. Yet, solutions to abate air pollution in port areas is controversial. To contribute to the relevant literature, this article aims to assess eco-efficiency for container terminals (CTs) inside a port when the unwanted output is taken into consideration. In doing so, the Slacks-Based Measure (SBM)-DEA model was adopted to evaluate the efficiency of CTs while the modality movement approach was deployed to estimate the amount of CO₂ released by CT operators. It is found that: (1) Wan-Han is the most efficient CT operator, with an average efficiency of 0.993 during 2017–2019; (2) the unwanted output (i.e., CO2) affects CT operators' efficiency score; (3) inefficient DMUs can improve their operating performance by adopting slack variables.