Energy Savings and Their Attribution in Sustainable Logistics Collaboration

Horizontal logistics collaboration can reduce energy use, yet evaluating coalitions by aggregate savings alone conceals how the savings are attributed to the participating firms. This methodological study uses synthetic data to examine how this attribution affects the ex ante evaluation of partner configurations. Coalition-level Energy-Saving Potential (ESP) is multiplied by a normalised Shannon-entropy term describing the balance of attributed savings, yielding the Entropy-Adjusted Energy Complementarity Index (EECI), a preference-dependent diagnostic measure. It is examined in an operational allocation example, a designed experiment, Monte Carlo simulations, and a multi-criteria model combining Analytic Hierarchy Process (AHP) and entropy weighting with the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and VIKOR (VIseKriterijumska Optimizacija I Kompromisno Resenje). At a fixed aggregate saving, EECI assigns higher scores to more balanced distributions; when aggregate savings differ, greater balance does not necessarily yield a higher score. In the operational example, the attribution rule alone changes the leading partner. In the designed example, the configuration with the largest saving loses its leading EECI position only when more than about 93% of it is attributed to one partner. In the multi-criteria model, the recommendation depends more on whether energy intensity and empty-distance reduction are included than on replacing ESP with EECI. The results describe the framework’s behaviour under controlled assumptions, not savings in real coalitions.