The conversion of energy regularly results in losses in the form of heat. This applies both for the conversion of kinetic energy of wind into electrical energy in the generator of a wind energy facility, where these losses regularly occur in the main driving line of the wind energy facility, and also for the electrical feeding of energy generated by the wind energy facility into a medium voltage network. For this purpose, regular devices of power electronics, e.g., rectifiers, and/or transformers, are necessary. In the main driving line, which is mounted in the nacelle for a wind energy facility, the losses occur overwhelmingly in the gears, at the bearings, and in the generator or at other control units, such as, e.g., in the hydraulic systems or similar control and regulation units, which adjust the rotor blades or turn the wind energy facility into the wind. For gearless wind energy facilities, e.g., model E-66 of Enercon, the main losses occur at the main driving line in the generator, i.e., in the nacelle (head) of the wind energy facility. The task of the invention is to prevent the previously mentioned disadvantages and to provide a cooling device for a wind energy facility, which reduces the losses of the wind energy facility. Wind energy facility with a completely closed or at least partially closed cooling circuit, with which the heat to be dissipated from the cooling circuit is dissipated by the tower or the nacelle of the wind energy facility.