US Patent 9074781 Automatic roof ventilation system

A roof ventilation system operable based on environmental parameters is disclosed. The system includes a vent, a fan, a solar panel, a battery and a controller. The vent is positioned within a field of a roof, and includes a first opening configured to allow airflow between regions above and below the roof. The fan is positioned to generate an air flow through the vent. The solar panel is positioned on the roof in a location such that the solar panel receives solar radiation. The battery is electrically connected to the solar panel. The controller is in communication with the fan, and is configured to drive the fan based on at least one environmental parameter.