Apparatus (2) for generating electricity from a tidal or ocean current water flow, which apparatus (2) comprises: a plurality of electrical generators (4) for generating electricity; and each electrical generator (4) comprises a rotor (8), a stator (10), and a housing (12); the housing (12) is a multi-sided housing constructed such that the electrical generators (4) are stably connected together; the apparatus (2) includes positioning means (20) for positioning the apparatus (2) above a waterbed (22); and the apparatus (2) includes position-adjusting means (24) for adjusting the height and/or the direction of the housing (12) such that the housing (12) is always able to be at a height and pointing in a direction for receiving maximum flow of water through the housing (12), and thereby to enable the apparatus (2) to generate a maximum amount of electricity from the water flow.

Apparatus (2) for generating electricity from a tidal water flow, which apparatus comprises: a plurality of electrical generators (4) for generating electricity; and connection means for electrically connecting the electrical generators (4) together; wherein each electrical generator (4) comprises a rotor (6), a stator (8), and a housing (10); the housing (10) is a multi-sided housing constructed such that the electrical generators (4) are stably connectable together; the housing (10) is open at both ends; the stator (8) is inside at least a part of the housing (10); the rotor (6) comprises a plurality of magnets (18) positioned around the periphery of the rotor (6); the magnets (18) are encased in a protective material (20) which protects the magnets (18) from the water; and the rotor (6) has vanes (22) which cause the rotor (6) to rotate within the stator (8) as the water flows through the housing (10).

A spar for use in a blade of a wind turbine comprises a plurality of rods having polygonal cross-sections bundled together into a bundle having a first plurality of rods disposed along a widthwise extent of the bundle and a second plurality of rods disposed along a heightwise extent of the bundle and means to secure rods within the plurality of rods to one another.

A diffuser component for a gas turbine is provided, where a fluid flow in the direction of a combustion chamber of the gas turbine can be slowed down by the diffuser component, and a flow cross-section of the diffuser component, which is defined by a diffuser wall is widened to do so. The diffuser wall is at least locally braced, in that at least one stiffening element with a lattice-type structure is provided on the diffuser wall.

A device for conversion of wave energy into electrical energy consists of a supporting structure, the first working body, an anchor and anchor cables. The supporting structure is connected to the anchors by anchor cables, while the first working body is slidably connected to the supporting structure. The motion transformation system is firmly connected to the supporting structure and comprises rigid gears toothed with gears with rolls on one side while on the other side they are hinged to the first working body, on the other side of the gears with the rolls, rigid gears are connected at one end, while their other end is hinged to other working body. The gears with rolls are connected by shafts with a multiplier that drives the generator that further produces electricity.

A vertical axis wind turbine is disclosed. The wind turbine may include a polygonal mast having a predefined count of faceted sides. The polygonal mast may include a mast top end and a mast bottom end. The wind turbine may further include a drive shaft having a polygonal drive shaft top end and a drive shaft bottom end. The polygonal drive shaft top end may be configured to connect the mast bottom end with the drive shaft. The polygonal drive shaft top end too may have the predefined count of faceted sides.

A device for conversion of wave energy into electrical energy consists of a supporting structure, the first working body, an anchor and anchor cables. The supporting structure is connected to the anchors by anchor cables, while the first working body is slidably connected to the supporting structure. The motion transformation system is firmly connected to the supporting structure and comprises rigid gears toothed with gears with rolls on one side while on the other side they are hinged to the first working body, on the other side of the gears with the rolls, rigid gears are connected at one end, while their other end is hinged to other working body. The gears with rolls are connected by shafts with a multiplier that drives the generator that further produces electricity.