Abstract
Sri Lanka's extensive coastline offers significant potential for wave energy extraction, providing a more reliable alternative to tidal and thermal energy sources. This study evaluates various wave energy conversion technologies to identify the most suitable method for integration with breakwaters. Among the methods evaluated, the overtopping devices demonstrated the highest efficiency, producing an average power output of 2981 W/m, with a peak of 5798 W/m during the Southwest (SW) monsoon. The oscillating water column (OWC) exhibited seasonal variation, reaching 3583 W/m during the SW monsoon and an average of 1772 W/m. The wave energy hyperbaric converters (WEHC), although stable, generated the lowest power output at 141 W/m during Inter Monsoon-1. A comparative analysis of breakwater-integrated wave energy systems indicated that the proposed design could achieve an annual power output of 1580 MWh for a 102 m stretch, closely approximating the 600 MWh output of the Mutriku Breakwater. The overtopping method proved to be the most energy-efficient, with 58% efficiency and 40% cost-effectiveness, while the WEHC method demonstrated 30% efficiency and 26% cost-effectiveness. Despite its advantages, the overtopping method underperformed between December and March, highlighting the need for hybrid solutions to ensure continuous energy production. Key challenges include structural durability, biofouling, and selecting the appropriate turbine. The use of advanced materials and optimized turbine designs is crucial for improving efficiency and extending the system's lifespan. Future research should focus on enhancing WEHC efficiency and incorporating energy storage solutions to address seasonal fluctuations. Overcoming these challenges will be essential to achieving a sustainable and cost-effective wave energy solution for Sri Lanka's coastal regions.