Dual-use wave energy opportunities in Caribbean Small Island Developing States: A screening framework for renewable energy and coastal protection

Wave energy is among the most promising renewable resources, but its widespread adoption has been constrained by its high levelized cost of electricity (LCoE). The dual use of wave energy converters (WECs) and wave farms for both coastal protection and renewable energy generation offers a promising pathway to lower costs while addressing coastal erosion. Despite this potential, no regional-scale assessment has yet examined the dual-use of WECs and wave farms in Caribbean Small Island Developing States (SIDS), where energy dependence and coastal erosion remain pressing challenges. This study develops a novel dual-use screening index to evaluate the combined potential of wave farms across four representative Caribbean SIDS: Barbados, Jamaica, St. Lucia, and The Bahamas. Long-term ERA5 wave data were used to estimate mean and maximum deep water wave power, while GEBCO bathymetry defined suitability zones (onshore, nearshore, offshore). Shelf area, wave power statistics, and zone-specific weights reflecting coastal protection benefits were combined into a standardized framework to enable cross-island comparison. Results highlight strong contrasts between islands: Barbados and St. Lucia exhibit wave power concentrated nearshore, suggesting strong dual-use potential, whereas Jamaica and the Bahamas trade lower wave energy resources for larger available shelf areas. The dual-use index highlights the most promising locations where energy generation and erosion mitigation can be jointly maximized. This study provides the first regional screening-level assessment of dual-purpose wave farms for Caribbean SIDS, combining wave resource indicators and coastal protection metrics to identify and rank candidate zones, introducing a transferable framework that links renewable energy potential with coastal protection benefits. The approach provides a foundation for future modelling, policy, and planning toward sustainable energy and coastal resilience, while offering actionable insights for Caribbean SIDS that advance both climate adaptation and progress toward the Sustainable Development Goals (SDGs). • First study to assess dual-use wave energy potential in Caribbean SIDS. • Integrated ERA5 wave data and GEBCO bathymetry for resource mapping. • Developed a novel dual-use screening index for energy and coastal protection. • Revealed new regional opportunities for coastal resilience and renewable energy. • Provides a foundation for future planning and SDG-aligned policies.