Prioritizing Renewable Energy Systems for Onshore Power Supply: An Entropy–TOPSIS Application for Ambarlı Port

Stricter environmental mandates in maritime transport have accelerated the adoption of onshore power supply (OPS) systems however, the actual decarbonization potential of OPS remains fundamentally contingent on the electricity source's carbon intensity. This study evaluates renewable energy system (RES) alternatives to power OPS operations at Ambarlı Port, Türkiye, focusing on five distinct options: onshore solar photovoltaic (PV), offshore floating solar PV, onshore wind, offshore wind, and wave energy. Seven technical, economic, and spatial criteria form the empirical basis of the assessment. To ensure an objective evaluation, an integrated Entropy--Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) framework is utilized, where the Entropy method derives criteria importance directly from data variability. Findings reveal that onshore solar PV is the most viable solution (Ci = 0.8342), with onshore wind serving as the primary alternative. Notably, the analysis suggests that cost-driven parameters currently outweigh environmental factors in the strategic decision-making process for port-side energy investments. This methodological approach offers a practical decision-support tool for port authorities aiming to align infrastructure planning with the International Maritime Organization (IMO) 2050 and FuelEU Maritime targets.