A vertical axis wind turbine with improved safety, production efficiency and greater functional wind speed range. A vertical axis wind turbine comprises turbine blades having geometric characteristics of a yin yang symbol when viewed from the top down. The turbine blades are configured to form a scoop portion for catching wind. The surface area of the scoop portion may be dynamically configured to accommodate power production in higher wind speed ranges by dynamically furling the blades to reduce the surface area of the scoop portion as RPM begins to exceed a safe limit. First and second permanent magnet rotor arrays are dynamically positioned above and below an array of stator coils to maximize power generation.

Method for retrofitting a lightning protection device of a rotor blade of a wind turbine. In the method, a cable section of a lightning protection cable is stripped of insulation. A connection piece and a lightning protection receptor are fitted to the cable section which is stripped of insulation, so that the lightning protection receptor is electrically coupled to the lightning protection cable. The invention also relates to a rotor blade which is retrofitted using the method. The risk of lightning strikes in specific regions of a rotor blade can be reduced by the invention by means of the retrofitting operation.

A floating wave energy converter intended to be installed in an aquatic environment comprising a surface, water and a bed, realized by a cylinder including an energy-production device, and connectors connected to anchors, wherein the connectors intersect.

A vertical axis wind turbine with improved safety, production efficiency and greater functional wind speed range. A vertical axis wind turbine comprises turbine blades having geometric characteristics of a yin yang symbol when viewed from the top down. The turbine blades are configured to form a scoop portion for catching wind. The surface area of the scoop portion may be dynamically configured to accommodate power production in higher wind speed ranges by dynamically furling the blades to reduce the surface area of the scoop portion as RPM begins to exceed a safe limit. First and second permanent magnet rotor arrays are dynamically positioned above and below an array of stator coils to maximize power generation.

A block type wave power generation apparatus of the present invention comprises: a floating unit for absorbing kinetic energy of waves and moored to the sea by a wire; a base unit for passing the wire extended from the floating unit therethrough and positioning the floating unit within a predetermined area of the sea; a power generation unit for transmitting kinetic energy of the floating unit from the wire passing through the base unit, and converting the kinetic energy into electrical energy.

A nanofriction power generation device with spiral vibrating balls and a buoy body thereof-includes an inner spiral barrel, an outer spiral barrel sleeved outside the inner spiral barrel, hollow balls between the two spiral barrels, an electric energy storage device contained in the inner spiral barrel, and a buoy barrel for containing the outer spiral barrel. The outer wall of the inner spiral barrel and the inner wall of the outer spiral barrel are respectively provided with first spiral tracks and second spiral tracks extending from one end to the opposite other end. The inner spiral barrel is in the outer spiral barrel, and the first spiral tracks and the second spiral tracks have a one-to-one correspondence and form spiral channels. Nanofriction electric generator films are attached to an outer surface of each hollow ball and an inner wall of each spiral channel.

A noise-reduction device for a wind turbine and the wind turbine applied thereof are introduced. The noise-reduction device has a body. The body has a connection portion and a spoiler. The connection portion is concavely disposed on one side of the body and corresponds in shape to the wind turbine's blade so as to be fixed to a confronting edge of the wind turbine blade. The spoiler is disposed on the opposing side of the body. As soon as the wind turbine blade is driven by wind, the spoiler stirs air and guides the air across two sides thereof. When guided by the spoiler, airflows turn into vortexes on the wind turbine blade; hence, the chance that the wind turbine will stall and generate noise is greatly reduced.

There is provided a wind turbine apparatus, comprising a wind turbine structure and an enclosure structure, which is easily transportable and capable of being mounted on moving vehicles or buildings during operation of the wind turbine apparatus. The wind turbine structure generates electric power from kinetic energy of natural wind and comprises of a plurality of vertical blades arranged in a circular manner to form a plurality of rotatable and integrally superimposed cylindrical compartments. The enclosure structure provides support and rigidity to the wind turbine structure and comprises of a plate at one end of the housing, a closed hollow base portion at an other end of the enclosure and a plurality of connecting columns to mechanically hold together the plate and the closed hollow base portion. The wind turbine structure is placed within the enclosure structure and a connecting shaft connects the wind turbine structure to the enclosure structure.

Aspects of the disclosure include a tidal power generator comprising a first container, at least one second container pivotably coupled to the first container, a frame pivotably coupled to the first container, a first valve, associated with the first container, configured to selectively control ingress of a first volume of a first fluid into the first container, and a second valve, associated with the first container, configured to selectively control egress of a second volume of the first fluid out of the first container.

An axial impeller has a tubular housing mounted on bearings for rotation. The housing is capable of engaging a motor or generator directly or through a drive belt. Interior turbine blades are mounted on the housing wall. The blades may be hinged so they can rotate between a retracted position adjacent to the wall and an extended radial position. Rods penetrate the wall to position the blades between retracted and extended positions. When extended, the blades may be rotated to propel a fluid through the housing; and when retracted natural fluid flow is less restricted.