A large-scale group decision-making method for site selection of waste to energy project under interval type-2 fuzzy environment

The waste to energy (WTE) project provides a promising solution for managing the rapidly generated municipal solid waste (MSW). To achieve the sustainable MSW management, it is essential to select an appropriate WTE plant site. Thus, this paper proposes a large-scale group decision-making method to select the optimal site. First, a sustainable evaluation index system is constructed based on the Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis from the perspectives of economic, environment, and society. Second, considering the linguistic terms provided by the decision makers cannot be directly computed, an interval data driven-based computing with word model is presented to transform the linguistic terms into the Gaussian interval type-2 fuzzy sets (IT2FSs). Then, a Gaussian interval type-2 fuzzy clustering approach is provided to conquer the inefficiency caused by the increase of the number of decision makers. Finally, the TODIM method is extended to compare and rank the alternative sites in the context of Gaussian IT2FSs. A case study is provided to illustrate the effectiveness of the proposed method, meanwhile, some discussions are conducted to illustrate the superiority and flexibility of the proposed method. The results indicate that the proposed method can successfully select the optimal plant site and has the potential to provide practical reference for the policymakers.