The Effect of Blade Overlap on The Performance of Savonius Wind Turbine

Abstract

Savonius wind turbine is a simple type of wind turbine that can generate electric power at low wind speed. This study used an L type two-bladed Savonius vertical axis wind turbine. The research objective was to conduct experiments to determine the effect of blade overlaps on the performance of the Savonius wind turbine in terms of cut in speed, tip speed ratio (TSR) and maximum power coefficient (Cp). The overlap variations used in this study are 0%, 10%, 13%, 15%, 20%, 25% and 28%. The wind tunnel test in the range of 2 m/s to 9 m/s wind speed found that 10% and 13% overlap ratios give the best spin of rotor and the highest efficiency in the form of power coefficient for higher wind speed, but it will decrease the ability of cut-in speed. Otherwise overlap ratios in the range of 15%–28% will generate power coefficient in the average of 26% and suitable for low wind speed conditions (3–5 m/s).