Abstract: A helmet air conditioning unit configured for operation with a helmet having air flow spaces within an interior space thereof, the helmet air conditioning unit including an electrical ventilating fan with a housing portion having one or more exhaust ports positionable in fluid communication with the air flow spaces within the interior space of the helmet; a battery power supply connected to energize the fan; a solar power supply coupled to recharge the power battery supply; and a fan controller coupled for actuating the fan for generating a pressurized air flow at the one or more exhaust ports of the housing portion of the fan, whereby the pressurized air flow is directed through the one or more exhaust ports of the housing portion of the fan when the fan is actuated.