Vortex-induced vibration triboelectric nanogenerator for low speed wind energy harvesting

We propose a novel vortex-induced vibration (VIV) based triboelectric nanogenerator (TENG) that makes it possible for efficient energy harvesting from wind at low speed. A theoretical model for VIV-TENG is constructed to investigate the vibration response and output voltage varying with wind speed, which is compared with and validated by experiments. Results show that there is a lock-in region where the vibration amplitude and output voltage are large. When the wind speed is 2.78 m/s, the average power is achieved to be 392.72 μW and the average power density is 96.79 mW/m2, which are much higher than those reported in previous studies. In order to broaden the lock-in region, we further design a new model of tandem vortex-induced vibration triboelectric nanogenerators. The resonance wind speed region is remarkably widened due to interactions between two cylinders subjected to VIV. The demonstration of continuously powering wireless sensors is performed to show the practicability of the designed VIV-TENG. Overall, the present study enables applications of TENG for realizing self-powered wireless sensing under low wind speed environments.