A wind turbine comprises a rotor with a certain number of blades, a stator supporting the rotor in such a way that the rotor may rotate on the turbine axis for generating electric energy and a shroud extending circumferentially around the stator and the rotor and supporting the stator so as to define an air channel of a certain air channel diameter at an inlet portion of the shroud. The shroud has a maximum outer diameter such that the air channel diameter is comprised in the range from 0.82 to 0.9 times the maximum outer diameter. Furthermore, the shroud has a length in direction of the turbine axis that is comprised in the range from 0.1 to 0.25 times the outer diameter.