A Prototype Automatic Solar Panel Controller (ASPC) with Night-time Hibernation

摘要

Solar cells, as an alternate means of electricity supply, is rapidly advancing. Generally, output of solar cells depends largely on intensity of sun and angle of incidence on the cells. This means that to get maximum efficiency from these cells, they must remain directly pointed at the sun from sun rise to sun set. However, the position of sun's highest intensity with respect to a given spot changes with time of the day. It is therefore necessary to automatically control position of solar cells to always align with the highest intensity of sun. In this paper, we present a prototype automatic solar panel controller, with night time hibernation. The proposed system consists of both software and hardware parts, and it automatically provides best alignment of solar panel with sun to get maximum intensity. The solar panel controller system detects the presence of sun rays using light dependent resistors (LDR). At the heart of the control mechanism is an AT89C52 microcontroller. It is programmed to constantly monitor the output of an LDR, actuate a stepper motor to reposition the solar panel to a direction with the highest intensity. The proposed system also has an option of manual control of the panel via a computer interface or a keypad unit for easy of user interactivity during maintenance. Testing the proposed system, results shows that it can successfully track the sun and enter idle mode in the absence of sun rays, hence, conserving over 50% of energy required to operate the system.