A wind power installation is provided having a pylon, a pod mounted rotatably on the pylon, a generator arranged within the pod and having a rotor and a stator, and at least one fan in the region of the pod. The fan may be adapted to blow air out of a rear part of the pod, through an air gap between the stator and the rotor and into a front part of the pod. A seal structure may be positioned in the pod in such a way that an air flow that bypasses the air gap between the stator and the rotor is substantially prevented.