A method of handling the pitch bearing unit of a rotor blade mounted to the hub of a wind turbine, the method including the steps of providing an extension assembly at the interface between the rotor blade and the hub, moving the rotor blade outward from the hub by means of the extension assembly to open a gap large enough to accommodate the pitch bearing unit while maintaining a connection between the rotor blade and the hub, and removing the pitch bearing unit through the gap.

An underwater power plant, a method and a system are for converting kinetic energy of flowing water into electricity. The power plant has at least one turbine house defining a duct for housing a turbine apparatus, and a connecting means for attaching the turbine apparatus in the duct. The connecting means has at least one member slidably connected to the turbine house for allowing sliding of the turbine apparatus out of, into or within the turbine house.

A wind turbine comprises a permanent magnet synchronous generator, a main converter, a main converter controller, a wind turbine master controller and an electrical power supply stage comprising an electrical energy storing device. A startup of the wind turbine can be performed using electrical energy from the electrical energy storing device independent from a power supplying grid and/or a combustion engine. After startup, the wind turbine can be operated in an island mode by controlling an intermediate voltage of the main converter by the main converter controller and retrieving power from the synchronous generator independent from the electrical energy storing device.

A wind turbine includes a nacelle which houses components including a generator connected to a rotor. The nacelle includes a cover and a skeleton, the skeleton including a plurality of connected elongated skeleton members. The skeleton members include a first skeleton member, a second skeleton member non-parallel to the first skeleton member, and a bolt extending in parallel with the second skeleton member for connecting the second skeleton member and the first skeleton member. Also, a method is presented for removing a component housed in a nacelle of a wind turbine, including disconnecting a second skeleton member from first skeleton members, removing the second skeleton member from a path of removal of the component, and removing the component along the path.

A method for mounting or dismounting a wind turbine component of an energy generating unit in a multirotor wind turbine is disclosed. The multirotor wind turbine comprises a tower configured to support one or more load carrying structures each arranged for supporting at least two energy generating units arranged at or near its ends and at opposite sides of the tower. The method comprises positioning or dispositioning a first wind turbine component at a first end of the load carrying structure, yawing the load carrying structure approximately 180 degrees, and positioning or dispositioning a second wind turbine component at the second end of the load carrying structure opposite the first end. The method may be used in erecting or servicing a multirotor wind turbine.

A wind turbine includes a nacelle which houses components including a generator connected to a rotor. The nacelle includes a cover and a skeleton, the skeleton including a plurality of connected elongated skeleton members. The skeleton members include a first skeleton member, a second skeleton member non-parallel to the first skeleton member, and a bolt extending in parallel with the second skeleton member for connecting the second skeleton member and the first skeleton member. Also, a method is presented for removing a component housed in a nacelle of a wind turbine, including disconnecting a second skeleton member from first skeleton members, removing the second skeleton member from a path of removal of the component, and removing the component along the path.

A fixture and methods of using the fixture that can be used in situ to perform repair and maintenance work on a generator shaft and associated components of a wind turbine generator is described. The fixture is typically mounted to a plurality of the threaded bores provided in the generator housing used to attach the generator's end bell or the gearbox/transmission to the generator, and provides a platform for attaching accessory fixtures to support the shaft of the generator, as well as, provide for the mounting of tools used to maintain and repair the generator shaft.

A method and associated system are provided for removing a drive train component, such as a gearbox, from a rotor shaft uptower in a wind turbine, wherein the component is supported by transversely extending mounting arms at mount locations on the wind turbine frame. The drive train component is supported from above or below and the mount locations. At each mount location, a removal fixture is installed that includes an actuator that moves linearly essentially parallel to the rotor shaft. The mounting arms are simultaneously engaged with the respective actuators, which are controlled to linearly push the mounting arms until the drive train component disengages from the rotor shaft.

Provided is an alignment tool for a cutting arrangement including a cutting apparatus with a cutting edge for treatment of a workpiece, especially a rotor blade of a wind turbine, in which the alignment tool includes at least one fixation means for fixing the alignment tool to the workpiece and at least one guiding structure to guide the cutting edge of the cutting tool.

A method for detaching or installing a rotor blade from or to a hub of a wind turbine includes positioning the rotor blade toward a ground location between a three o'clock position and a nine o'clock position. The method also includes mounting a mechanical arm to an uptower location of the wind turbine. Further, the mechanical arm includes a torqueing tool at a distal end thereof. Thus, the method also includes removing or installing, via the torqueing tool, each of the plurality of hub fasteners so as to detach or attach the rotor blade from or to the hub.