Effects of Wind Angles and Wind Speeds on Voltage Generation of Savonius Wind Turbine with Double Wind Tunnels

Abstract This paper proposes effects of wind angles and wind speeds on capability of voltage generation of a savonius wind turbine with double wind tunnels. The savonius wind turbine under the study was designed to convert wind flows with opposite directions, such as wind flows due to the movement of vehicles that could be seen at the isles, into electricity. The prototype wind turbine had both diameter and height of 32 cm and had its shaft connected to an electric DC generator. Two tunnels with input and output wind areas of 1,980 and 782 cm2 each were used to increase wind speeds by 2.5 times for the turbine. The experimental results showed that the wind angles between 23.2 – 35.5 degrees provided high levels of generated voltages when the wind angle of 30 degrees provided the highest voltage among the wind angles of 0-90 degrees. The faster the wind speeds, the higher levels of generated voltage, i.e. the wind turbine generated peak voltage between 7.28-11.28 volts for the wind speeds between 4.86-6.41 m/s. In addition, the savonius wind turbine with double tunnels could generate output voltage at almost all the wind angles (60 to -75 degrees) whilst the conventional savonius wind turbine without tunnels could generate voltage only in the wind angle range of 17-38 degrees, as well as, with higher voltage levels for all wind speeds approximately by 45-68%.