A two-stage GIS–MCDM framework for wave energy farm site selection – A case study in Sri Lanka

Green energy solutions, inspired from the Paris Agreement on global warming reduction efforts, are pertinent in mitigating carbon emission and the global energy investment in recent decades. Sri Lanka, an island nation in the Indian Ocean, possesses significant potential for marine renewable energy, particularly offshore wind and wave energy. As wave energy remains the least developed, identifying suitable locations for Wave Energy Farms (WEFs) is crucial. This study proposes a two-stage decision-making framework tailored to Sri Lankan conditions, integrating Geographic Information Systems (GIS) and Multicriteria Decision-Making Methods (MCDM) extended with Monte Carlo Analytic Hierarchy Process. The first stage defines feasible zones using exclusionary criteria, while the second stage employs a Fuzzy Analytical Hierarchy Process (FAHP) to prioritise sites based on technical, environmental, socio-economic, and cultural factors. Results show that 5.04% of Sri Lanka's Exclusive Economic Zone (EEZ) constitutes the Area of Interest (AOI), with 0.03% classified as highly suitable, 30.07% moderately suitable, and 69.90% marginally suitable. The identified Potential Installation Areas (PIAs) overlap with offshore wind zones, highlighting strong synergies that can enhance Sri Lanka's renewable energy share. Accordingly, the findings offer actionable insights for stakeholders and investors in Sri Lanka's sustainable energy sector.