Comparison the effectiveness of three outranking multicriteria methods as analytical tools for the efficiency assessment of biorefineries/ waste-to-energy technologies

Circular Economy is at the heart of the EU Green Deal, Europe’s new agenda for sustainable growth. Waste Management has been firmly focusing on material and energy recovery, through the development of policy schemes and the utilization of resource recovery facilities. Waste-to-energy technologies are in the forefront of this effort because they allow the utilization of wastes which are considered of low value and that cannot be incorporated in other recovery schemes (like recycling). Rigorous methodologies for the evaluation of the different waste-to-energy technologies (e.g. waste incineration plants, anaerobic digestion plants) are necessary for the efficient comparison of the available options and for proposing the most suitable solutions in each scenario. Several thermodynamic assessment methodologies have been presented in the exiting literature and the focus of this study will be on the 3T method and the R1 formula. These assessment methods utilize modified thermodynamic calculations for the overall evaluation of a given waste-to-energy technology and both have been proved to be effective for conventional energy surplus cases. Nonetheless, in scenarios where the focus is on the production of materials (e.g. the case of biorefineries) and there is an energy deficit, the thermodynamic methods have some limitations. In this study, we utilize various Multi-Criteria Decision Analysis (MCDA) methodologies for the assessment of waste-to-energy gasification plants. The analysis was performed by integrating the 3Tmethod parameters in three different outranking Multi-Criteria Decision Analysis methodologies, i.e., the methods PROMETHEE, TOPSIS, and ELECTRE, in order to provide an integrated assessment of the operation of Waste-to-Energy systems. The MCDA methods are able to successfully develop results by creating rankings of preference for the analyzed technologies. Nonetheless, each MCDA method uses a different mathematical approach (algorithm) for the conversion of the input data into numerical values for the unicriterion and the multicriteria analysis. In this study, we investigate the optimal outranking MCDA method for the case of biorefineries/ waste-to-energy technologies. Finally, we demonstrate how MCDA methods can be used for the analysis of the thermodynamic characteristics of Waste-to-Energy plants on the basis of qualitative and quantitative criteria, and how they can be used to support decision making.