Patent ID: 7364406

Claim:
An apparatus powered by a fluid flow for generating electricity, the apparatus comprising: a center axis configured for rotating in response to the fluid flow; a top rotor element coupled to the center axis, the top rotor element including an arm extending substantially perpendicular to the center axis, the arm of the top rotor element movable in response to the fluid flow to effect the rotation of the center axis; a bottom rotor element coupled to the center axis, the bottom rotor element including an arm extending substantially perpendicular to the center axis, the arm of the bottom rotor element movable in response to the fluid flow to effect the rotation of the center axis; and a plurality of intermediate rotor elements stacked between the top rotor element and the bottom rotor elements; and wherein each intermediate rotor element includes a tongue and a groove for coupling to the adjacent rotor element; and wherein the arm of the bottom rotor element is substantially fixed in a position relative to the arm of the top rotor element, wherein the position is offset about the center axis by about 90° from the top rotor element; and wherein the intermediate rotor elements are in positions successively offset about the center axis in degrees to produce the 90° offset of the bottom rotor element relative to the top rotor element.