Development and Experimental Investigations on Multi-blade Vertical Axis Savonius Wind Turbine

Abstract

Worldwide interest in renewable energy systems has been increased intensely due to rapidly growing energy needs, scarcity of fuels, global warming and other issues. Wind power is a major source of sustainable energy and can be harvested using both horizontal and vertical axis wind turbines. In current scenario, the horizontal axis wind turbine is the recent trend for wind energy utilization for power generation. However, they are suitable for higher wind velocity and subjected to higher cost and complex system; which puts limitation in their applications for domestic applications. To overcome these problems and to utilize the wind energy even at low velocity and at low cost, vertical axis wind turbine is one of the attracting alternatives. The main limitation of Savonius vertical axis wind turbine is low power coefficient. In the present study, an attempt has been made to improve its performance by carrying out parametric study. In view of this, the multi-blade vertical axis Savonius wind turbine system was developed and installed at M/s Techen Polkcon, Sanand. On the system, experimental investigations were carried out to study the effects of various parameters like number of blades (viz. 2, 3, 4 and 5) and angle of blades (viz. 35°, 45°, 52°, 60° and 70°) in the wide range of wind velocity. The lowest cut-in speed was observed to be 1 m/s for 5-blade turbine. Analysis concluded that, the wind turbine system under consideration works best with 5 no of blades oriented at 60° and gives max efficiency of 34%.