DIY Solar Tracker: Harvest Maximum Sunlight

A Solar Tracker is a device that orients a solar panel towards the sun to maximize energy capture. Fixed panels lose efficiency as the sun moves across the sky; trackers solve this.

Types of Trackers

• Single-Axis: Follows the sun from East to West.
• Dual-Axis: Also adjusts for the sun's altitude (seasonal tilt). More complex but more efficient.

How It Works (using LDRs)

We use 4 Light Dependent Resistors (LDRs) placed on 4 corners of the panel.

1. Compare Light: The microcontroller reads the resistance (inverse of light intensity) from all 4 LDRs.
2. Find Direction: If the left LDRs get more light than the right, the sun is to the left.
3. Adjust Servo: The Arduino commands a servo motor to rotate the panel towards the brighter side until all LDRs are balanced.

Components

• Arduino Uno
• 4x LDRs + Resistors
• 2x Servo Motors (for dual-axis)
• Solar Panel
• 3D Printed or Metal Frame

Applications

• Small-scale home solar installations.
• Educational demo of renewable energy.
• Final year project for EEE/ECE students.

Related Project

Check out our LDR Based Automatic Street Light, which uses the same LDR sensing principle!