Experimental study on a Savonius wind rotor for street lighting systems

This paper investigates the aerodynamic performance of a Savonius vertical axis wind rotor to be used in an innovative lamppost. The wind generator studied is the main part of a public lighting system (a street lamp) powered by both aeolian and solar renewable energy sources. This study is aimed to analyze the effects of different construction solutions on rotor performance. Experimental dynamic tests were carried out on a 1:1 rotor model in the Environmental Wind Tunnel (EWT) of University “Politecnica delle Marche” (UNIVPM); tests were performed at different wind velocities and for different construction combinations. The results obtained confirmed that, in the tested range 2-3.3 × 105, rotor performance does not depend on the Reynolds number. Tests also showed that the presence of end plates and blade overlap increases the power coefficient CP,max, while the presence of external grids and structural posts has negative effects on rotor performance. The best results were obtained for a configuration having a helical rotor with a 105° twist, open blade overlap and end plates.