Evaluation of the hybrid renewable energy sources using sustainability index under uncertainty

As a result of continuous growth in population, efforts to meet increasing energy demand in a balanced way in the future as it is today, has led to the emergence of the sustainability concept. Sustainability is mainly considered with technical, economic, environmental and social aspects, hence the most effective instruments to ensure sustainability are renewable energy technologies which are interchangeably used for sustainability. Renewable energy problems regarding sustainability have inherently conflicting goals with a high degree of ambiguity and complexity. To address these problems, multi-criteria decision making (MCDM) approach serve best. Therefore, in this study, a MCDM approach integrating Pythagorean fuzzy sets (PFSs) in AHP–TOPSIS method combination was used to calculate the sustainability index and for ranking renewable energy technologies, hybrids and battery energy storage systems (BESSs) in Turkey. The sustainability index was handled in three main aspects, i.e., uninterrupted supply, economic supply and environmentally friendly supply. The results pointed out that hydro + solar and wind + solar hybrid alternatives have the highest sustainability index value while geothermal and biomass rank as the lowest two alternatives energy technologies.