Evaluation of seaport equipment performance using multi-directional efficiency analysis for sustainable logistics operations: A case from Portugal

Seaports are critical nodes in global supply chains, making it essential to analyze equipment efficiency to optimize their operations, reduce costs and operational times, while also acknowledging environmental concerns to meet current stricter sustainability goals. This study evaluates the performance of cranes and loading arms at the Portuguese Port of Sines, employing Multi-Directional Efficiency Analysis (MEA) to address limitations in traditional efficiency measurement methods like Data Envelopment Analysis (DEA). MEA uniquely accounts for both desirable (cargo weight) and undesirable (CO${}_2$ emissions) output variables, alongside operational input variables (energy consumption and duration). The analysis reveals significant efficiency differences across equipment categories, uncovering unexpected insights for equipment managers. It reveals consistently underperforming units, such as the GRUA LIEBHERR 40 T crane, and exemplary performers, including the QC09 crane and Braço de Carga 9. Notably, this study bridges a research gap by introducing MEA to seaport logistics, offering a comprehensive evaluation framework that integrates environmental and operational metrics. Key findings highlight actionable insights for decision-makers, e.g., prioritizing equipment upgrades or defining stricter maintenance schedules. These findings underscore MEA's potential as a decision-support tool for enhancing resource utilization, reducing costs, and fostering sustainable operations in the maritime logistics sector. In addition, future research directions are explored in the manuscript's last section.