Low profile wind savonius turbine triboelectric nanogenerator for powering small electronics

Wind energy is one of the abundant sources present in nature. To meet future needs of clean and sustainable energy, there are many alternates arising day by day in the market. Here, we propose a simple design of sliding-mode triboelectric nanogenerator (TENG) as a wind energy harvester by adopting savonius-type vertical axis wind turbine. The blade shaft is affixed with a circular acrylic sheet, which is an upper friction layer of the TENG. A static friction layer is made up of Kapton tape. Accordingly, the revolution of the wind turbine induces continuous triboelectrification and electrostatic induction at the friction layers. Savonius TENG has been experimented on at varying wind speeds and observed in certain conditions. The fabricated TENG produced 25 µA short circuit current (Isc), open-source voltage (Voc) was recorded at 40 V on 8 m/s wind speed. The maximum power obtained from the TNEG was up to 50 µW power, whereas 110.58 Wm⁻² power density at the contact area 144 cm² of TENGs was achieved. By adjusting the thicknesses of the triboelectric layer and electrodes, the TENG underwent an optimization process that resulted in a substantial enhancement of its overall performance. To our knowledge, such remarkable power density represents the highest value ever reported for savonius TENG. Having the high output characteristics, the fabricated savonius TENG successfully delivered power to 25 blue-coloured light-emitting diode. The power generated from savonius TENG has been provided to the energy storage unit and maintained uninterruptable supply to small electronics like the thermometer, and digital watch. According to our best knowledge, the savonius wind turbine design has been used first time with the nanogenerator in this paper. The fabricated Savonius TENG is one of the promising solutions to drive small electronics and can be operated on very low wind profiles.