A hybridized water wave energy harvester with a swing magnetic structure toward intelligent fishing ground

Wave energy is one of the most abundant energy sources in the ocean with a vast range of distributions, large-scale reserves, and high energy density. A hybridized triboelectric-electromagnetic energy harvester is demonstrated as an efficient method for harvesting wave energy. Here, a hybridized water wave energy harvester (H-WWEH) is proposed based on a swing magnetic structure with a permanent magnet as the mass block. Benefiting from the swing magnetic structure including a permanent magnet with polyester fiber (PET) friction layer adhered on the surface, the H-WWEH can harvest the water wave energy in any direction. When the H-WWEH is excited by the motion of the water wave, the friction layer will slide on a bottom friction layer to generate electric energy. At the same time, a coil installed under the bottom friction layer is used to scavenge the magnetic energy during the movement of the permanent magnet. By optimizing the length of the swing string, setting the electrode of TENG as Tai Chi shape, and specifying the connection between triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) parallel, the output voltage and current of TENG and EMG can reach 90 V and 0.61 μA, 5.3 V and 6.4 mA with the wave at a low frequency of 1.75 Hz in a simulated water environment. On the basis of the prominent performance, a self-powered wireless wave height alarm system for the intelligent fishing ground is built, and the wireless transmission is spontaneous through the inclination switch. It demonstrates that the H-WWEH has the potential to drive distributed and self-powered marine environment monitoring sensors.