This work presents the design and development of a cost-effective and effective Dual Axis Solar Tracker system based on the ATmega32 microcontroller. Unlike conventional fixed or single-axis trackers, the dual-axis tracker maximizes the collection of solar energy by tilting the panel in the azimuth (horizontal) and elevation (vertical) axes. Four Light Dependent Resistors (LDRs) arranged in a quadrant are utilized to calculate the direction of maximum sunlight. Based on the analog input from the sensors, the ATmega32 compares and processes light intensities to generate PWM signals that drive two servo motors that are used for real-time panel positioning. A comparative study with a fixed panel under the same conditions indicates a 20–35% increase in energy output. This paper stresses the feasibility of constructing an intelligent, autonomous sun tracking solution utilizing low-cost elements, showing much promise for household, business, and rural electrification systems.
Introduction
The growing environmental concerns and depletion of fossil fuels have accelerated the demand for sustainable energy solutions, with solar energy being a leading eco-friendly option. The efficiency of solar panels significantly depends on their orientation relative to the sun. Fixed panels are simple but inefficient, as they cannot adjust to the sun's movement. Solar tracking systems improve energy capture by adjusting panel angles throughout the day.
Single-axis trackers follow the sun’s east-west movement but neglect seasonal vertical changes. Dual-axis trackers, however, adjust both azimuth (horizontal) and elevation (vertical) angles, maintaining optimal perpendicular alignment to the sun and enhancing energy efficiency.
This paper presents a cost-effective dual-axis solar tracker based on the ATmega32 microcontroller. The system uses four Light Dependent Resistors (LDRs) arranged in a cross to sense light intensity from different directions. The microcontroller processes this data and controls two servo motors via Pulse Width Modulation (PWM) to align the panel dynamically.
Previous works showed improvements but had limitations like single-axis tracking, lack of vertical alignment, and no real-time monitoring. This project addresses these by implementing a closed-loop control system with real-time analog sensing, scalable design, and potential IoT integration.
The hardware includes the ATmega32 microcontroller, LDR sensors, two servo motors for azimuth and elevation control, and a regulated power supply. The software, programmed in embedded C, reads sensor inputs via ADC, compares intensities, and commands servo movement accordingly.
Testing and observations demonstrate that the system effectively adjusts panel orientation throughout the day—tilting eastward in the morning, reaching maximum tilt at solar noon, and following the sun westward in the afternoon—maximizing solar energy capture compared to fixed panels.
Conclusion
The constructed Dual Axis Solar Tracker using ATmega32 successfully demonstrates an efficient and real-world means of optimizing solar energy harvesting by maintaining the solar panel aligned with the sun\'s position at every instant. By employing four LDR sensors for detecting sunlight intensity and servo motors for controllable panel movement, the system cleverly maximizes solar exposure throughout the day.
The project not only exhibits the combination of analog sensing (via LDRs) and digital control (via ATmega32\'s ADC and PWM modules), but also exhibits an affordable solution with simple electronic components, thus being able to be afforded by low-cost industrial applications as well as educational use. Real-time feedback from the LCD interface provides an additional level of usability and diagnostic capability for the system.
With experimental testing and simulation in Proteus, the tracker was proven to increase solar panel orientation efficiency significantly compared to fixed-angle panels. The system optimizes adaptation to changing directions of sunlight, minimizes human effort, and optimizes energy production with minimal power consumption.
References
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