A novel integrated system of wave-current attenuation device and triboelectric nanogenerator with an aim to harness blue energy and provide protection

The integration of wave energy converters (WECs) with floating breakwaters is a well-established strategy to enhance cost-effectiveness and improve efficiency (United Nations (UN) Sustainable Development Goals). However, the potential for integrating triboelectric nanogenerators (TENGs) with floating breakwaters remains to be explored. This study proposes a novel integrated system that combines a floating wave-current attenuation device with a TENG, thereby addressing this research gap. The effects of draft depth, wave-facing area, and mooring cable tension on the electricity generation, hydrodynamic response, and protective effect of an integrated system under wave-current excitation were thoroughly studied in a large wave-current flume. Furthermore, particle image velocimetry (PIV) technology was utilized to measure current velocity and field variations in a designated area behind the integrated system, allowing for the observation of water particle motion trajectories. The findings indicate that the integrated system not only excels in electrical output characteristics but also demonstrates favorable hydrodynamic properties. The system exhibits commendable turbulence performance, with a current transmission coefficient of approximately 0.50 for the wave-facing area. Additionally, the integrated system significantly reduces the motion response of the protected structure compared to scenarios without it. This study validates the performance and feasibility of integrating TENGs with floating wave-current attenuation devices.