A supplemental wind propulsion power system for a vehicle having at least one battery. The system includes an air intake duct disposed on the vehicle for intercepting turbulent airflow created by the forward motion of the vehicle, an air conduit, an air turbine disposed at the outlet of the air conduit and a generator for supplying electricity to the batteries. The system further includes an air filtration system, an air heating system and grid output terminal to provide a port for supplying supplemental electricity to the electrical grid.