Vehicular air conditiong apparatus comprising hybrid compressor

In the vehicular air conditioning apparatus according to the present invention, for a drive source, either the vehicular engine or an electric motor may be selected and connected to the compressor. According to the control of the present invention, the main controller of the air conditioning apparatus always calculates both of the compressor power consumption which occurs if it is driven by the engine and the compressor power consumption which occurs if it is driven by the electric motor. Comparing the results of these calculations, the main controller connects the less energy consuming drive source to the compressor. By this selective control of the drive source of the compressor, it is possible to save effectively the total energy consumption of the vehicle.