Underwater vehicles capable of self-propulsion are described. An underwater vehicle includes a cross-flow turbine including two or more foils spaced apart from a main shaft. The foils have a pitch that is adjustable under control of a pitch control mechanism. The underwater vehicle also includes a frame supporting the main shaft. The frame enables rotation of the cross-flow turbine. The underwater vehicle additionally includes a generator-motor set including rotor and stator elements. The rotor element is in rotary communication with the main shaft.

A vertical axis wind turbine includes two or more cells arranged one above the other along a vertical machine axis, wherein each of the cells includes a plurality of vertical blades which are arranged within the cell distributed on a concentric circle about the machine axis and which are connected so as to be able to move together on this circle and which are rotationally fixed with a main shaft, and wherein the blades in the cell are each individually mounted so as to be able to rotate about a vertical axis of rotation which in particular runs internally through them.

In a vertical rotor apparatus that rotates in response to a moving fluid, a shaft defines an axis of rotor rotation. Rotor blades are longitudinally aligned in parallel with the shaft and each rotor blade defines an axis of blade rotation. A sensor generates a signal when any of the rotor blades are within rotor azimuthal angles of blade stall regions. A controller generates blade pitch information for the blade stall regions and an actuator, which is mechanically coupled to each of the rotor blades, alters blade pitch about the axis of blade rotation in accordance with the blade pitch information.

A hydroelectric power plant for a water stream includes an electromechanical converter and a turbine driving the converter. The turbine includes two vertical supports parallel to the flow and, between the supports, driving blades moved by the hydrodynamic lift forces, connected at each end to a drive component. The turbine further includes wheels driven by the drive component and assembled on the supports. The hydroelectric power plant includes at least first, second, and third travel areas where each drive component extends rectilinearly, the leading edges of the blades being arranged horizontally plus or minus 5 at least in the first and second travel areas. Each support includes guides and each blade includes elements abutting against the guides.

In one embodiment, a turbine shaft transmits mechanical power, a vane support structure is coupled to the turbine shaft, a vane is coupled to the vane support structure through a vane shaft, a balancing weight is coupled to a first location of the vane, and an alignment weight is coupled to a second location of the vane.

A vertical wind turbine that includes a plurality of vertical vanes which is secured to a vertical vane axis so as to be rotatable independently of one another about a respective vane rotational axis and which are rotatably mounted about a vertical rotor rotational axis on a common circular path. A method for operating a vertical wind turbine, in which method pitch angles of vertical wind turbine vanes driven about a respective vertical vane axis are specified. The vertical wind turbine is operated in a particularly efficient and material-preserving manner by control of the pitch angles, at least in a partial load mode of the vertical wind turbine, such that the vanes rotate with a substantially constant tip-speed ratio.

A vertical wind turbine that includes a plurality of vertical vanes, each of which is secured to a respective vertical vane axis so as to be rotatable about a respective vane rotational axis independently of one another by a motor and which are mounted on a common circular path in a rotatable manner about a vertical rotor rotational axis. A method for operating a vertical wind turbine. Angular positions about a respective vertical vane axis are specified for driven vertical vanes of the vertical wind turbine. The vertical wind turbine is operated in a particularly efficient and material-preserving manner in that the angular positions of the vanes are permanently regulated by directly driving the vanes using a pitch motor arranged concentrically to the respective vane axis.

A vertical wind turbine that includes a plurality of vertical vanes which can be rotated independently of one another about a respective vane rotational axis by a motor and which are mounted on a common circular path in a rotatable manner about a vertical rotor rotational axis. A method for operating a vertical wind turbine. Angular positions are specified for vertical wind turbine vanes which are mounted in a rotatable manner about a respective vertical rotor rotational axis and which can be rotated about a respective vane rotational axis by a motor. The vertical wind turbine is operated in a particularly efficient and material-preserving manner in that the angular positions of the vanes are specified by at least one respective pitch motor which at least partly supports the respective vane.

A variable-pitch vertical axis wind turbine comprises a hub supported for rotation about a central axis and a blade pivotally mounted to the hub so as to permit relative rotation between the blade and the hub. The blade and the hub define a pitch angle therebetween. The wind turbine comprises a mechanism configured to produce reciprocating motion during rotation of the hub about the central axis. The wind turbine comprises a linkage configured to transfer the reciprocating motion produced by the mechanism to the blade so as to vary the pitch angle.

The present invention relates to a hydroelectric power generator using ebb and flow of seawater. More particularly, the hydroelectric power generator is able to continuously generate power through high tide and low tide created according to a tidal difference that continuously occurs, while being submerged in seawater, using a marine current that flows fast. The hydroelectric power generator is also able to utilize eco-friendly energy that does not require a reservoir by adjusting the amount of inflow of seawater and to be installed at various places, while being varied in size, as necessary.