An attempt is made here to increase the output of a Savonius rotor by using a flow deflecting plate. When the deflecting plate is located at the optimum position, the rotor power increases nearly 30 percent over that when no deflecting plate is present. The rotor torque was found to become almost zero, when the plate is placed just in front of the rotor. In addition, two systems to control the rotational speed of a Savonius rotor are developed. These permit the rotor to be stopped in strong wind. Operating characteristics of the two control systems are investigated.