Trackers
Motorised mounts that turn panels to face the sun as it crosses the sky.
How trackers work
A tracker mounts a row of panels on a rotating tube. A small motor, guided by a controller that knows the sun’s position, tilts the row to face east in the morning and west in the evening. Dual-axis trackers can also tilt up and down, but they are more complex and less common.
Why they are used
Because the panels face the sun more directly for more of the day, a tracked system generates noticeably more energy than a fixed one with the same panels. The gain is largest in sunny places with clear skies, which is why trackers are standard at many large solar farms.
Advantages and limitations
Advantages
- More energy per panel
- Flatter output across the day
- Works well with bifacial panels
Limitations
- Higher upfront and maintenance cost
- Moving parts can fail
- Needs more space between rows
Current development
Software is making trackers smarter, using weather forecasts and "backtracking" to avoid rows shading each other, and moving panels to safe positions in storms.
Further reading
- Solar tracker (Wikipedia)Types of tracking systems