Assessing Container Terminals’ Environmental Efficiency: The Modified Slack-Based Measure Model

Abstract

The classic Slack-Based Measure (SBM) model has been posited to be a favorable non-parametric tool to cope with undesirable output. Nevertheless, this model has two significant drawbacks that should be addressed in practice. Thus, this paper aims to revise the classic SBM model to estimate container terminals’ environmental efficiency with undesirable output. The originality of this article includes: (1) introducing the energy consumption method to calculate the quantity of CO2 emitted by container terminal operators (CTOs), (2) adopting cluster analysis to identify homogeneous CTOs acting as Decision-Making Units (DMUs), and (3) introducing the modified SBM model to measure and analyze environmental efficiency for CTOs. Based on this research, the efficiency of the analyzed terminals and the management of the local port sector are improved.