Patent ID: 8128337

Claim:
An omnidirectional, vertical-axis two-stage wind turbine comprising: A) a base that forms first and second vertically juxtaposed and interconnected chambers, said first chamber being below said second chamber, B) a shaft connected to said base and extending vertically through said first and second chambers for rotation about a vertical axis, C) a plurality of angularly spaced horns connected to said base about the periphery of a first of said two chambers, each horn having an outer mouth and an inner throat whereby the pressure and velocity of the wind at the inner throat is greater than the pressure and speed of the wind entering the outer mouth, D) first energy conversion means in said first chamber and fixed to said shaft for converting energy of the wind exiting said horns into a first component of mechanical energy for rotating said shaft and for deflecting the wind toward said second chamber as a primary exhaust air with vertical and angular velocity components, E) stationary redirection means intermediate said first and second chambers and fixed to said base for redirecting the primary exhaust air to produce a substantially laminar upwardly vertical flow toward said second chamber, said redirection means including: i) a central hub concentrically mounted with said shaft whereby said shaft is free to rotate relative to said redirection means, and ii) a plurality of angularly spaced, radially extending fins forming vertical passages between said central hub and said base intermediate said first and second chambers, and F) second energy conversion means in said second chamber and fixed to said shaft for converting the energy in the laminar exhaust from said redirection means into a second component of mechanical energy that transfers to said shaft thereby to increase the total mechanical energy transferred to said shaft.