0 125 inch and the maximum slot is 4 250 inches this is self adjusting in the preferred embodiment illustrated so that the electricity generating wind turbine is responsive to both low and high wind velocity in the preferred example the wind turbine starts at about 3 knots and reaches maximum power at 30 knots the self adjustment of the radial position of the blades and the consequent slot width is a function of the balance of the inward and outward forces on the blades the inward force results from the spring force and this spring force varies with gap as a function of the spring rate the outward force is the centrifugal force which is a direct function of the rotative speed and the aerodynamic lift of the blade as it moves through the air the ovate cross section of the drum is an improvement of the aerodynamics at the venturi section defined by the gap the ovate section of the drum is essentially made up of two concentric circles with specific points on each connected with a continuous spline in the preferred size with a substantially 12 inch diameter drum a drum length of 281 2 inches will produce a wind.