Efficiency assessment of switchgrass cultivation areas using sustainable indicators under epistemic uncertainty

•Considering switchgrass as an appropriate feedstock for bioethanol production.•Proposing sustainability indicators for evaluating switchgrass cultivation areas.•Developing a unified data envelopment analysis model under epistemic uncertainty.•Conducting a case study in Iran for verifying and validating the proposed model. This paper proposes a unified fuzzy data envelopment analysis model to address the optimization of switchgrass cultivation locations based on sustainable development indicators under epistemic uncertainty. In this study, each potential switchgrass cultivation location is considered as a decision making unit and a range-adjusted measure is utilized as a data envelopment analysis model for calculating the unified efficiency of each potential location for switchgrass cultivation and determining the most appropriate ones. By reason of the epistemic uncertainty associated with sustainable indicators, fuzzy set theory is incorporated in the proposed model. Inasmuch as the values of a number of indicators used in the model are in the form of possibility distributions, a new possibilistic programming approach is used for transforming the unified fuzzy data envelopment analysis model into an equivalent crisp one. The proposed model is verified and validated by comparing its results with those of the equivalent crisp one through performing a real case study in Iran at different levels of uncertainty. The computational results demonstrate the applicability of the proposed model in determining the appropriate locations for switchgrass cultivation based on sustainable development and under uncertainty.