2010 Prius-III?s Denso A/C unit ? A study in efficiency

Much of the energy consumed by a vehicle's A/C system is used by the compressor to compress the refrigerant. In conventional air conditioning systems, an expansion valve is used to reduce the pressure of the refrigerant before passing it through the evaporator to cool the air. DENSO's new system uses an ejector instead of an expansion valve. The ejector recovers expansion energy, which was previously lost in the expansion valve, and converts it into pressure energy. This, reduces the compressor's workload and helps reduce the air conditioner's overall power consumption.