Sustainability and technical assessment of oil storage techniques using a hybrid Fuzzy AHP-VIKOR approach

Oil storage is a strategic necessity, but each storage technique—above-ground, underground, and in-ground—has distinct strengths and drawbacks, and growing sustainability demands complicate the choice of the best option. This study, therefore, develops a structured multi-criteria decision-making (MCDM) framework that integrates technical, economic, social, and environmental factors to identify the most appropriate oil storage technique. Using a structured literature review and expert consultation, four main criteria and sixteen sub-criteria were defined. The Fuzzy Analytic Hierarchy Process (F-AHP) was then applied to elicit expert judgments and compute weights, while Fuzzy VIKOR (F-VIKOR) was used to rank the alternatives. The results indicate that the social criterion is the dominant factor, with safety being the most influential sub-criterion, followed by return on investment. The F-VIKOR analysis ranks underground storage as the best option, above-ground storage as second, and in-ground storage as third, with underground storage satisfying both the acceptable advantage and stability conditions. Sensitivity analyses confirm that underground storage remains the top-ranked technique under all weighting scenarios, although the rankings of above-ground and in-ground techniques interchange when economic and social weights change. This study offers decision-makers a robust and evidence-based tool for strategic planning and policy-making regarding strategic oil storage options.