Double-blade structured triboelectric–electromagnetic hybrid generator with aerodynamic enhancement for breeze energy harvesting

Wind energy is a form of renewable energy with excellent development prospects. However, low-speed wind energy has not been effectively explored and utilized. To this end, a double-blade structured triboelectric–electromagnetic hybrid generator (DB-TEHG) is designed in this paper, which can efficiently harvest breeze energy by using double-blade structured design to improve the aerodynamic performance of the device. The improved blade structures directly drive the triboelectric nanogenerator (TENG) and electromagnetic generator (EMG) without requiring additional transmission systems. The blade parameters are simulated and optimized using computational fluid dynamics to enhance the wind energy harvesting capability of the device. The minimum starting wind speed of DB-TEHG is found to be 2 m/s. The output performance of a single TENG unit is 910 V, 45 μA, 280 nC, and the peak power is 4 mW, and that of the EMG is 236 V, 24.2 mA, and a peak power of 0.5 W, when the wind speed is 5 m/s. It is also found that at this wind speed the DB-TEHG can convert wind energy into electricity output with an efficiency of 20.88%. The demonstration results prove that the proposed DB-TEHG can power a wireless thermometer by harvesting outdoor natural wind energy. This paper presents the application potential of DB-TEHG in the Internet of Things and also provides a novel solution to harvest breeze energy by combining TENGs and EMG.