Integral fans
WARNING: This page is about a different car, the 2003 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.
Courtesy of SAAB-SCANIA OF AMERICA, INC.
Heat that builds up in the generator while it is running can eventually cause damage. To dissipate it, the generator has two integral fans, powered from the rotor shaft.