From the point of view of energy saving, this will certainly increase the consumption of cars.
The streamlined body design aims to reduce the wind resistance of the vehicle as much as possible. According to aerodynamics, if you add a protrusion on a profiled surface, this protrusion will definitely increase the wind resistance coefficient of the vehicle. vehicle, that is, the resistance to driving the car increases.
According to the capacity conservation relationship, due to the efficiency problem of the wind turbine, there is mechanical wear and energy loss, so in the principle of receiving the same capacity , the power generated must be less than the resistance received by the car.