A device and method of acquiring mechanical energy by using a wind power generator employing sails is described. A sail is mounted on a towing carriage that is used for the rotation of a propulsion wheel of the mechanical gear is added. The towing carriage is connected to a strand and the strand transfers the force originated by the sail to the propulsion wheel of the power plant. The sail has the ability of adjustment of its angle position to the direction of the wind, the total exploitation cycle of the wind power generator employing sails consists of the working part during which the sail is moving along the direction of wind.

The lengths and/or chords and/or pitches of wind turbine or propeller blades are individually established, so that a first blade can have a length/chord/pitch that is different at a given time to the length/chord/pitch of a second blade to optimize performance and/or to equalize stresses on the system.

The lengths and/or chords and/or pitches of wind turbine or propeller blades are individually established, so that a first blade can have a length/chord/pitch that is different at a given time to the length/chord/pitch of a second blade to optimize performance and/or to equalize stresses on the system.

The lengths and/or chords and/or pitches of wind turbine or propeller blades are individually established, so that a first blade can have a length/chord/pitch that is different at a given time to the length/chord/pitch of a second blade to optimize performance and/or to equalize stresses on the system.

A rotor blade of a wind turbine, comprising a first rotor-blade portion and a second rotor-blade portion. In this case, the first and the second rotor-blade portion constitute a total length of the rotor blade and, upon a rotation of the rotor blade, the first rotor-blade portion and the second rotor-blade portion can be moved relative to each other, along a longitudinal axis of the rotor blade, as a result of a centrifugal force acting upon the rotor blade, in such a way that the total length of the rotor blade can be altered.

The present invention presents a structure for a set of cable-stayed blades for variable-speed wind turbines with the aim of manufacturing low-cost, large-capacity wind turbines with blades of up to 200 meters long, do not rotate to change the tilt of the wing, insulated from turbine shaft, the structure includes the steel tube at the center of the central hub for affixing the blade set onto the head of the wind turbine shaft, a tower to extend the turbine vertical axis for mounting stay cables which are fastened to the axial bearing blade frame, the blade body consists of a triangular prismatic frame with two rear-framing tubes parallel to each other to form the baselines for mounting blade surface sheets which can be furl/unfurled, the blades can be disassembled and placed into containers to be transported to the base of the turbine tower for assembly.

A method of determining and controlling the attack angle of a fixed-speed wind turbine blade involves determination of an appropriate angle of attack for optimal extraction of wind energy at low to medium wind speed, which includes three steps: 1defining basic parameters of the turbine including blade length and width, fixed rotational speed, rated wind speed, start-up speed and the lowest speed at which the turbine is forced to stop, and a relationship with wasted power; 2defining wind speed based on a set of attack angles calculated to form an overall optimal attack angle of the wind turbine blade; and 3calculating necessary physical parameters to come up with the most effective method of controlling the turbine blade so that the turbine can be directly connected to the grid, making wind power costs as low as those of other conventional energy sources.

An energy generating device for generating energy from a flowing fluid, especially from a wind flow and/or from a water flow, comprises: a rotation body, the rotation body extending along an axis of rotation between a first point and a second point and the rotation body being adapted to rotate about the axis of rotation and the rotation body being formed from at least a first, a second, and a third rotation segment, wherein the rotation segments are joined together and arranged along the axis of rotation, and they form a region at least partly surrounded by fluid, wherein the second rotation segment is situated between the first and the third rotation segment and has a different diameter than the first and third rotation segment; and a generator device mechanically connected to the rotation body, wherein the generator device is adapted to generate energy which is produced from the rotation of the rotation body.

The lengths and/or chords and/or pitches of wind turbine or propeller blades are individually established, so that a first blade can have a length/chord/pitch that is different at a given time to the length/chord/pitch of a second blade to optimize performance and/or to equalize stresses on the system.

The lengths and/or chords and/or pitches of wind turbine or propeller blades are individually established, so that a first blade can have a length/chord/pitch that is different at a given time to the length/chord/pitch of a second blade to optimize performance and/or to equalize stresses on the system.