A power supply is contained substantially within an enclosure of length, L. A first end of the enclosure has a first end wall containing an air intake port, with a second end of the enclosure having a second end wall containing an air exhaust port. An exterior wall surrounding the power supply is coupled to the first and second end walls so that substantially all air entering the power supply does so through the air intake port and all air leaving the power supply does so through the air exhaust port. The enclosure contains an airflow generator for inducing an air flow within the enclosure from the air intake port to the air exhaust port, located at least a distance L/5 from the air intake port and air exhaust port.