Abstract: A Savonius three bladed vertical axis wind turbine rotor has operational characteristics superior to those of conventional three bladed rotors. The blades have high curvature and a high skew factor, for example a curvature of greater than about 7:1 (preferably at least 5.5:1, e. g. 2:1-5:1), and a skew factor of greater than about 0.6 (preferably at least 0.7, e. g. about 0.75-0.9). Preferably the rotor also includes at least one substantially vertical shaft, the blades operatively connected to the shaft. The rotor typically has an aspect ratio of at least about 0.8:1, preferably at least about 2:1 (with the aspect ratio of each blade about twice that of the rotor). The blades desirably comprise a plurality of substantially aligned spokes axially spaced along the shaft each spoke comprising three generally radially extending ribs arcuately spaced from each other approximately 120 degrees.