Numerical and Experimental Power Output Estimation for a Small-Scale Hinged Wave Energy Converter

Abstract

Wave energy converters (WECs) integrated into breakwaters present a promising solution for combining coastal protection with renewable energy generation, addressing both energy demands and environmental concerns. Additionally, this integration offers cost-sharing opportunities, making the overall investment more economically viable. This study explores the potential of a hinged point-absorber WEC, specifically designed as a floating hinged half-sphere, by assessing the device's power output and comparing two different breakwater configurations. To evaluate the device's performance, a comprehensive numerical and experimental approach was adopted. Numerical simulations were carried out using a radiation-diffraction model, a time domain tool for analyzing wave-structure interactions. These simulations predicted average power outputs of 25 kW for sloped breakwaters and 18 kW for vertical breakwaters located at two strategic sites: the Port of Leix & otilde;es and the mouth of the Douro River in Portugal. To validate these predictions, a 1:14 scale model of the WEC was constructed and subjected to testing in a wave-current flume, replicating different sea-state conditions. The experimental results closely aligned with the numerical simulations, demonstrating a good match in terms of relative error and relative amplitude operator (RAO). This alignment confirms the reliability of the predictive model. These findings support the potential of integrating WECs into breakwaters, contributing to port energy self-sufficiency and decarbonization.