Design, Construction and Installation of Sun Tracking Operated Solar Street Lighting System

Abstract

This project is a design, construction, and installation of a sun-tracking operated solar street lighting system. An automatic solar tracker increases the efficiency of the solar panel by keeping the solar panel aligned with the rotating sun. Solar tracking is a mechanized system to track the sun’s position that increases the power output of the solar panel than the stationary system. In order to achieve this, two Light Dependent Resistors (LDRs) are mounted on the solar module to automatically “track” the progress of the sun through the day, thereby maximizing output. The unique feature of this design system is that instead of taking the earth as its reference, it takes the sun as a guiding source with an innovative alignment procedure for accurate and precise alignment between LDR and the panel so that maximum energy is achieved. At maximum, the solar tracker was perpendicular to the light source by 1.5 degrees. The built system had a calculated annual energy gain of 48.982% compared to the conventional practice where solar panels are fixed mid-way between the geographical east and west with approximately 30 degrees towards the south. For synchronization purposes, two active sensors; LDR (light dependent resistor) constantly detects the sunrise and ultrasonic sensors detect the east position while the servo motors rotate the panel towards the direction where the intensity of sunlight is maximized. The two systems are driven by a microcontroller ATMEGA 328P programmed in c-language. It was found out that the output on this system charges the battery at a faster rate and discharges slowly making the brightness of the lamp at its maximum brightness. It is therefore recommended that if the number of batteries is increased, larger motors, incorporates microcontroller to monitor more LDRs, more PV modules, there would be a wider coverage of provision of security lights and it has low maintenance.