A novel fuzzy integrated MCDM model for optimal selection of waste-to-energy-based-distributed generation under uncertainty: A case of the City of Cape Town, South Africa

Abstract

The aim of this paper is to select appropriate waste-to-energy (WtE) technology considering both subjective perspective of decision-maker and objective evaluation of the actual performance metrics of each alternative. Based on this premise, a novel hybrid multi-criteria decision making method based on Fuzzy-analytic hierarchy process (Fuzzy-AHP), Fuzzy-Entropy and Fuzzy-Multi-Objective Optimization on the basis of Ratio Analysis plus full multiplicative form (Fuzzy-MULTIMOORA) is applied as a decision tool. In this study, four (4) alternative WtE technologies (i.e., anaerobic digestion, incineration, pyrolysis and gasification) with fourteen (14) sub-factors that cut across four sustainability aspects (i.e., technical, economic, environmental and social factors) are considered. The applicability of the model is tested for a WtE technology selection in the City of Cape Town, South Africa. The result obtained reveals that for all the alternatives considered, the most sustainable WtE technology for investment in the City of Cape Town follows the order: anaerobic digestion > gasification > pyrolysis > incineration. Sensitivity analysis shows a high degree of consistency, robustness, and stability in the obtained results. The current work recommends that the integration of anaerobic digestion and gasification should be promoted as it has the potential to offer a well-balanced WtE technology compared to the stand-alone systems. Although, the case study is a city in South Africa, the methodology could be applied for selecting WtE technology in any developing countries’ city with similar waste characteristic and economic nature like that of South Africa.