Device for generating electrical energy from the airstream

The device has a rolling wind generator (3) arranged within a closed body of a motor vehicle (1) and behind a radiator grill (4), in a travel direction of the motor vehicle. Adjustable inner slats are arranged between the radiator grill and the rolling wind generator such that the rolling wind generator influences an airstream of the motor vehicle based on the velocity of the motor vehicle. The airstream is passed through the radiator grill and subsequently passed through the rolling wind generator by the inner slats.