Abstract: A vehicle refrigeration system (100) is provided for cooling an enclosed space within a trailer (14). The vehicle refrigeration system (100) includes a compressor unit (138) operatively coupled to a condenser (142) and an evaporator (144). The compressor unit (138) includes an electric compressor motor (140) coupled to a power controller (130) for coupling motor (140) to either a primary or a secondary source of power, and cycling the compressor motor on and off responsive to a signal from a temperature sensor (22). A primary power source unit (110) includes air driven turbine generator unit (112) affixed to the tractor (12) for generating electrical power responsive to relative displacement of the vehicle (10) with respect to the ambient air (16). Air driven turbine generator unit (112) is defined by at least one air turbine (114) rotatively coupled to at least one generator (116), the generator's output being coupled to power controller (130) for energizing the compressor motor ( 140).