An arrangement is for use in any of installing or replacing a part, maintaining, and constructing a wind turbine, the arrangement having a longitudinal structure at least partially supported on a wind turbine tower, a guide track connected to the longitudinal structure and a dolly arranged to follow the guide track along the longitudinal structure.

A wind turbine assembly includes a falling weight system to store potential energy within the wind turbine assembly. The falling weight system utilizes a pair of gears that can rotate to raise and lower weights within a cavity of the tower section. In addition, an assembly ring that is configured to climb a tower section of a wind turbine assembly may be used to assemble a wind turbine assembly or to perform maintenance on wind turbine assemblies. In some examples, a ballast weight system utilizing a ballast weight tank that lowers by being filled with water may be used to input rotational energy into a generator to create electricity.

Rotor lifting yoke for lifting a three bladed rotor, said rotor lifting yoke comprising: a lifting structure, a first and second flexible elongated element arranged to be connected both to the lifting structure and to a root portion of a first blade of the rotor, and a third and fourth flexible elongated element arranged to be connected both to the lifting structure and to a root portion of a second blade of the rotor. The rotor lifting yoke further comprises one or more length adjusting mechanisms which are arranged to adjust the effective length of the first and third and/or the second and fourth flexible elongated elements. The flexible elongated members are further arranged such that when said flexible elongated members are attached to the root portions of their respective blades, at least one point on the first and third and/or at least one point on the second and fourth flexible elongated elements is attached to their respective blades via a non-slip attachment. In this way, a rotor lifting yoke is provided which can rotate the rotor from a vertical to a horizontal position and back again in an easy and flexible manner just by adjusting the lengths of the flexible elongated members.