Identifying suitable offshore wind, wave, and hybrid energy sites with integration into the Turkish grid in the NE Mediterranean Sea

Transition toward renewable energy sources has become a critical global priority. Offshore wind and wave energy stand out due to their large potential; however, stand-alone systems often suffer from significant temporal variability, leading to unstable energy supply. In this context, hybrid systems may provide a more stable and cost-effective alternative by exploiting the complementarity between resources. This study identifies suitable locations for offshore wind, wave, and hybrid energy systems along the northeastern (NE) Mediterranean Sea, specifically evaluating their feasibility for integration into the Turkish grid and coastal infrastructure through an integrated Geographic-Information-Systems and Multi-Criteria Decision-Making framework. Eleven exclusion criteria and nineteen evaluation criteria were adopted, and their weighting was determined using an Analytic Hierarchy Process (AHP) evaluated on the basis of an expert survey. The novelty of this research lies also in the simultaneous evaluation of wind, wave and hybrid systems using real power data, and in the integrated consideration of variability and sustainability metrics across technical, environmental, and socio-economic dimensions. To assess the continuous productivity, a new index, Continuous-Productivity Index (CPI), was also proposed in the present study. The analysis revealed that the highest suitability indices were achieved near İzmir and along the Aydın coastline for both individual and hybrid applications. In the southern coasts where wind potential is limited, integrating wave energy into a hybrid system significantly enhanced spatial suitability. These findings offer a strategic roadmap for sustainable offshore energy planning in the region.