DESIGN AND CONSTRUCTION OF A DUAL-AXIS SOLAR TRACKING SYSTEM WITH UV AND LDR SENSORS ON AN ARDUINO-BASED SOLAR PANEL FOR A 50-WATT LOAD CAPACITY

Abstract

The utilization of solar energy as a renewable energy source in Indonesia remains suboptimal because static solar panels cannot follow the apparent movement of the sun. This condition can reduce solar irradiance absorption, particularly in the morning and afternoon, resulting in lower solar panel output power and less effective battery charging. This study aims to design and test a dual-axis solar tracking system based on an Arduino Mega 2560 to improve solar radiation absorption on a 100 Wp monocrystalline solar panel with a 50 W DC LED lamp load. The research employed a Research and Development (R&D) method with a quantitative descriptive approach. The system uses four Light Dependent Resistor (LDR) sensors to detect the direction of incoming sunlight and control the movement of the panel along the azimuth and elevation axes using two NEMA 23 stepper motors driven by TB6600 drivers. An ML8511 Ultraviolet (UV) sensor is used to monitor changes in ultraviolet radiation intensity during the tracking process. The system is equipped with a 12 V 100 Ah LiFePO4 battery and a Solar Charge Controller (SCC). Testing was conducted for seven days from 08:00 to 16:00 WIB by comparing the performance of the dual-axis solar tracking system with a static solar panel. The results showed that the dual-axis solar tracking system produced an average irradiance of 753.36 W/m², UV intensity of 4.39 mW/cm², and output power of 59.42 W, compared with 592.16 W/m² and 46.58 W, respectively, for the static solar panel. The tracking system also generated 3.33 kWh of electrical energy, compared with 2.61 kWh for the static system, resulting in an energy difference of 0.72 kWh over the seven-day testing period. The higher output power also increased the battery charging current, resulting in faster charging of the 12 V 100 Ah LiFePO4 battery. These results indicate that the proposed dual-axis solar tracking system can improve solar irradiance absorption, electrical energy production, and battery charging performance compared with a static solar panel.