• a support;
• a rotor mounted on the support for rotation about an axis, the rotor including a first blade and a second blade disposed symmetrically about the axis, the rotor having a cross section defined by a plane perpendicular to the axis, the rotor in the cross section including the first and second blades, each having:
• an outer edge and an inner edge with the outer edge moving in a path of a first circle around said axis, said circle defining a diameter of the rotor;
• a substantially linear portion extending from the inner edge toward said outer edge and terminating at a first location, said inner edge extending substantially beyond said axis on a side thereof opposite said outer edge and spaced from said first circle by a distance less than about 0.2 times said diameter, said linear portions of said first and second blades being substantially parallel;
• a first curved portion which is substantially an arc of a second circle, said first curved portion tangent to the substantially linear portion at said first location, said first curved portion terminating at a second location, said first curved portion tangent to said first circle at said second location; and
• a second curved portion tangent to the first curved portion at said second location and substantially coincident with said first circle.

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• Augmentation of Power in Slow-Running Vertical-Axis Wind Rotors Using Multiple Vanes, Sivasegaram et al., Wind Engineering, vol. 7, No. 1, 1983, pp. 12-19. 
• Design of a Prototype Improved Savonius Rotor: "As A System Totality", Rao, pp. 967-973 (no date). 
• Article entitled "Vertical Axis Wind Rotors-Status and Potential", from Wind Energy Conservation, pp. 28-29 (no date, but published prior to date of application). 
• "The Savonius Super Rotor!" by Michael Hackleman reprinted from the Mother Earth News, No. 193 (no date, but published prior to date of application). 
• Mechanical Engineering, Vo. 53, May 1931, No. 5, "The S-Rotor and Its Applications" by Savonius. 
• The Wind Power Book by Jack Park, 1981, pp. 93-95. 
• Newsletter 1, A Supplement to Wind and Wind Spinners, Jul. 1975, pp. 1-26. 
• "Wind Tunnel Performance Data for Two-and Three-Bucket Savonius Rotors", Report No. SAND 76-0131, Jul., 1977 authored by Blackwell, et al. 
• Paper Presented at the Second International Symposium on Wind Energy Systems, held in Amsterdam, Netherlands, Oct. 3rd-6th, 1978, vol. 2, pp. F3-30 to F3-34. 

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