A multi-criteria sustainability assessment approach for energy systems using sustainability triple bottom line attributes and linguistic preferences

Regarding the high level of pollution in energy industries, evaluating the current sustainability level in energy systems in developed/developing countries remains a challenge. A sustainable energy system has to proceed simultaneously social, economic and environmental practices with the goal of enhancing the sustainability level in associated systems. The evaluation of sustainability plays an active role in implementation of short- and long-term sustainability practices. This study proposes a novel framework as a benchmark for evaluations of sustainability in energy systems by introducing sixty-five key attributes and thirteen criteria for three pillars of sustainability. Due to the existence of incomplete information and uncertainty in evaluations of sustainability, the linguistic terms are used for expressing the condition of weight and performance rate for every single attribute based on expert judgment in accordance with fuzzy logic. Triangular fuzzy membership functions are also deployed to assign those linguistic judgments with appropriate fuzzy sets. The outputs of the proposed methodology involve a three-level fuzzy computational approach for obtaining the overall energy system’s sustainability index, using Euclidean distance approach for determination of sustainability level, a sieve algorithm for identifying the obstacles of sustainability using fuzzy performance importance index and finally enhancing the overall sustainability level with optimizing the identified weak points. An illustrative case is also resolved using proposed approach to elucidate the wide application of proposed framework in diverse energy systems/companies. The validation of approach is clarified by crisp calculations. The findings of this study will contribute policymakers and practitioners to take appropriate steps toward improvement of energy corporations.