Development of a Single-Axis Sun Seeker using Three Sensors

The output power generated by the solar photovoltaic panel is directly proportional to the amount of solar energy it receives. Therefore, for maximum efficiency, a solar photovoltaic panel must be perpendicular to the sun. As a result of this, a tracking device is required to ensure that solar panels are always directly perpendicular to the direct component of the sun. Such a tracking device is referred to as a sun seeker. This research work describes the development of a single-axis sun seeker using three sensors. Light-dependent resistors are used as sensors. The light intensity received by two of the sensors is compared by two comparators and an appropriate signal is sent to the driving mechanism which moves the solar panel tray until the right and left sensors receive an equal amount of light intensity. The middle sensor was designed to activate the speed control unit of the system when it senses the required light intensity. The whole system runs on a 12V rechargeable battery. A battery charger circuit with automatic cut-off was incorporated to the design to keep the battery topped-up and to prevent overcharging.