Abstract: A hat including an encased fan unit and an array of solar cells is described. In a preferred embodiment the fan unit is a low profile fan unit having a total thickness of less than 15 mm. The fan is typically located on the back of the hat's body providing airflow over the head and through the hair of a wearer thereby facilitating evaporative cooling processes. The array of solar cells is arranged the surface of a brim of the hat and comprises flexible thin film type solar cells. Preferably, the solar cells are electrically connected in a series parallel relationship.