Maritime spatial planning (MSP) is a mechanism of supporting adaptive decision making in response to possible conflicts over offshore wind turbine locations. The main purpose of this study is to determine the location of potential offshore wind turbine sites in the Northern Aegean Sea in Turkey by creating a geographical information systems-based marine spatial planning system for the region. A decision model has been proposed in which GIS and multi-criteria decision-making techniques are used to determine alternative areas. While the analytic hierarchy process (AHP) was utilized to identify viable sites based on several essential physical factors in this study, the Fuzzy TOPSIS approach was used to compare the Gökçeada, Bozcaada, and Enez study regions and find the optimal area. In the final stage, the areas where offshore wind turbine's locations are calculated are energy and exergy efficiency.