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.

Abstract: A Savonius vertical axis wind turbine rotor, that is effective yet relatively easy to manufacture, includes a number of spokes, vanes, and fasteners. Each spoke has a hub having a central opening, three at least partially arcuate ribs extending radially outwardly from the hub with inner (concave) and outer (convex) surfaces, and a number of channels defined in at least one of the inner and outer surfaces. The vanes are of sheet material generally conforming to an inner or outer surface of a rib and have openings aligned with the channels. First fasteners pass through the openings and cooperate with second fasteners provided in the channels. Each spoke is desirably in three substantially identical pieces, each piece comprising a hub segment and a generally radial rib. Two of the spoke pieces may be joined by a bridging piece, and two of the pieces joined by a clamping mechanism which draws the pieces toward each other to reduce the size of the central opening to clamp onto a shaft in the central opening.

Abstract: A Savonius vertical axis wind turbine rotor is versatile, simple and easy to construct and assemble, and efficient. The rotor includes at least three spokes, at least two vanes, and fasteners. Each spoke (which may be laser cut from aluminum plate) includes a hub having a substantially central opening, typically two or three at least partially arcuate ribs substantially integral with the hub and extending substantially radially outwardly from the hub with inner and outer surfaces, and a plurality of channels defined in at least one surface (preferably the outer surface) of each rib. The vanes are of sheet material (e. g. aluminum or polycarbonate) generally conforming to an inner or outer surface of a rib ahd have openings operatively aligned with the channels. First fasteners pass through the openings into the channels and cooperate with second fasteners provided within the channels to securely hold the vanes to the ribs; the fasteners are preferably removable.