A shape shifting foil alters the shape of a fluid foil contour by rotating a leading edge structure. A skin that forms the fluid foil contour is at least partially attached to the leading edge structure, and is wrapped around the leading edge structure so two edges of the skin form the trailing edge of the fluid foil. The two edges forming the trailing edge slide with respect to one another, thereby permitting the skin to shift when the leading edge structure is rotated.

A wind turbine is disclosed. The wind turbine includes comprising an inflatable portion comprising one or more blades and a device for rotatably driving the inflatable portion at a predetermined rate for a predetermined time.

A control method for a wind turbine, in particular for a wind turbine blade is described. The control method makes use of the blade mode shapes, or natural vibration shapes, of the blade to detect the excitement level of the blade natural vibrations, and controls active lift devices on the blade in an effort to reduce the excitement levels, to reduce loading in the blade and the overall wind turbine structure. There is also provided a method of designing a wind turbine blade for use in such a method.

Various air deflector shapes, sizes and configurations for use in a load compensating device on an airfoil are provided. The air deflector arrangements are configured to alter the airflow around the air deflector in order to affect sound or acoustics associated with the air deflector when deployed during operation. Some example configurations that may alter the air flow around the air deflector include air deflectors having a plurality of apertures, air deflectors including a scalloped edge, and/or air deflectors including a plurality of protrusions extending from a portion of the air deflector.

A windmill for generating electricity is described, which contains several improvements that enable the blades of the windmill to be much wider than conventional electricity-generating windmill blades. The rotor containing the blades will also change direction to capture the largest amount of wind energy available. The windmill includes a shroud surrounding the blades, which increases the wind velocity through the blades. Support structures for the windmill are described, and also a method of using the windmill to store electricity to use later is shown. The windmill is more stable than conventional windmills. A method of using a windmill to generate electricity is also described.

An apparatus may include a cage that rotates around a cage axis and a turbine located at an end of the cage and rotating around a turbine axis. A turbine blade may have an adaptable shape. A frame of the turbine blade may have a first frame portion that pivots relative to the second frame portion. The curvature of the turbine blade may be controlled by shortening a connection while concurrently lengthening another connection. Controllers may control the rotation of the cage(s) and/or turbine(s) based on a speed, a direction, a velocity, an acceleration of wind, and/or a load carried by the apparatus. The apparatus may be a Savonius machine. Rotation of the cage(s) and/or turbine(s) may induce a Magnus effect. A seat and user controls near the seat may be included. The user controls may control the rotation of the cage(s) and/or turbine(s).

The present subject matter directed to a rotor blade assembly for a wind turbine having at least one rotatable aerodynamic surface feature configured thereon. The rotor blade assembly includes a body shell including a pressure side surface and a suction side surface extending between a leading edge and a trailing edge. The aerodynamic surface feature is disposed adjacent to the pressure side surface, the suction side surface, and/or both. In addition, the surface feature may have a generally airfoil-shaped cross section. As such, an actuator can be configured at least partially within an internal volume of the surface feature, the actuator being configured to rotate the surface feature relative to the body shell.

An adjustable lift regulating device (30, 32, 40, 50, 52, 56, 60, 68, 72, 76) on an inboard portion of a wind turbine blade (28). The lift regulating device is activated to reduce lift on the inboard portion of the blade by causing flow separation (41) on the suction side (22) of the blade. To compensate for the lost lift, the blade pitch is increased to a running pitch that facilitates stalling on the outer portion of the blade in gusts. This provides passive reduction of fatigue and extreme loads from gusts while allowing full power production under non-gust conditions.

An apparatus may include a cage that rotates around a cage axis and a turbine located at an end of the cage and rotating around a turbine axis. A turbine blade may have an adaptable shape. A frame of the turbine blade may have a first frame portion that pivots relative to the second frame portion. The curvature of the turbine blade may be controlled by shortening a connection while concurrently lengthening another connection. Controllers may control the rotation of the cage(s) and/or turbine(s) based on a speed, a direction, a velocity, an acceleration of wind, and/or a load carried by the apparatus. The apparatus may be a Savonius machine. Rotation of the cage(s) and/or turbine(s) may induce a Magnus effect. A seat and user controls near the seat may be included. The user controls may control the rotation of the cage(s) and/or turbine(s).

A wind generator system with a plurality of lightweight, surface area adjustable airfoil/sail blades. Each blade is triangular or wedge shape with a narrow inner edge and a wide outer edge. Each blade includes an inner frame connected to a rigid mast that extends radially from a hub assembly. Each blade includes a curved outer skin layer that extends over the inner frame and configured into air foil shape with a large curved leading edge and a thin trailing edge. The outer skin layer is secured along its leading edge and removeably attached along its trailing edge to the inner frame. Advertising is printed on the outer skin of at least one blade that is visible. Coupled to the outer skin layer is a first linear actuator that when activated, causes the outer skin layer to fold or unfold thereby changing the blade's surface area. The internal frame may include a second linear actuator and a telescopic mast over which the blade slides to increase or decrease the sweep area of the blades. Wind or electrical sensors are coupled to the mast and the retractable cable to automatically control the sweep area and the surface areas.