How Solar Tracking Systems Work: Types, Pros & Cons
In the world of solar energy, one exciting technology is the solar tracking system. Put simply, this is a way to make your solar panels follow the sun, instead of just sitting fixed in one position. For anyone installing a sun tracking solar panel setup, whether a ground-mounted system, or part of a commercial rooftop system, understanding how solar tracking works, its benefits and drawbacks, and the different types available can help you make an informed decision. In this blog we’ll dive into the concept, show how it works, explore types, and weigh pros and cons, especially in relation to an on-grid solar system or large commercial rooftops. What is a Solar Tracking System? A solar tracking system is a mechanical and control system that adjusts the orientation of a solar panel or array of solar panels so that they face the sun more directly throughout the day. In contrast to a fixed tilt system (where panels remain in one angle, fixed in place), a tracker shifts the panel’s position to optimise the amount of sunlight hitting the panel surface. Why does this matter? The more direct sunlight hits the panel (i.e., the smaller the angle between the sun’s rays and the panel surface), the more solar energy the panel can convert. So for large-scale installations like commercial rooftop systems or a ground-mounted on-grid solar system, tracking can increase output and therefore improve return on investment. In simpler terms: imagine your panels are like faces turning to the sun as it moves, rather than staying turned away. That extra direct exposure adds up. How Does a Solar Tracking System Work? Here’s a breakdown of the working of a solar tracking system: Components & Basic Function Solar sensors or light detectors (sometimes sun position algorithms) detect the sun’s direction. A control unit gathers the sensor data, computes where the sun is or will be. Actuators or motors drive the physical movement of the panels (or the mounting structure). The panel array moves to maintain a more optimal angle to the sun throughout the day (and sometimes across seasons). The system is connected to the rest of your solar panel installation: The panels feed into the inverter, which connects to the grid (in an on-grid system) or to batteries/off-grid components (if applicable). Typical Operation in an On-Grid Solar System In an on-grid solar system, where your solar panels supply electricity to the grid (or offset your utility usage), tracking helps you maximise midday and afternoon output when demand (and often tariffs) are higher. For a commercial rooftop system, this means more production during peak hours, which can mean better economics. Real-world Considerations The structure must be able to rotate or tilt; this means stronger mounting, more open space (in many cases) and sometimes more complex foundations. Maintenance matters: motors, gears, sensors, and mechanical parts require upkeep (especially in dusty, harsh environments). The gain from tracking depends on your location (latitude, climate, shading, roof orientation) and the type of system you have. Types of Solar Tracking Systems There are several ways to classify solar tracking systems. Below are the main types and how they differ: 1. Based on Axis of Movement Single-Axis Solar Tracker: The panel rotates around one axis (usually east-to-west) to follow the sun as it rises and sets. Dual-Axis Solar Tracker: The panel rotates around two axes (east-west plus north-south tilt) so it can follow the sun both across the day and through the seasons. 2. Based on Mechanism Active Trackers: Use motors, gears and sensors to move the panels actively. Passive Trackers: Use physical/thermal mechanisms (e.g., fluids that expand/contract) to tilt the panels without motors. Simpler, but less precise. Manual Trackers: Someone physically adjusts the panels periodically. Rare in large systems. 3. Application-based Classification Ground‐mounted systems: Large installations, often utilising trackers because there is space. Commercial rooftop systems: Sometimes tracker may be used if space and structure allow, but less common than ground mounts because of rooftop constraints. Residential rooftop: As most sources note, trackers are often not cost-effective here because of space, structure and cost constraints. Advantages of Solar Tracking Systems Here are the benefits of using solar tracking systems (for example, in an on‐grid commercial rooftop project or a large ground‐mounted solar energy installation): Increased Energy Output: By keeping panels aligned with the sun, you can boost energy generation. Some sources note increases of 15-40% or more compared with fixed panels. Better Use of Space: If your land area is limited (for example in a commercial rooftop or grounds near your facility), a tracker allows you to get more yield per panel or per square metre. Higher Production During Peak Hours: Because the panel orientation is optimised, performance improves during morning and late‐afternoon hours, not just at solar noon. Flexibility Across Seasons (especially dual-axis): Dual-axis trackers adjust for seasonal sun height changes, making them especially useful in higher latitudes or where seasonal variation is large. Potentially Faster Payback (for large systems): For commercial or ground‐mounted systems, the extra yield may compensate for the extra cost and lead to better economics over the system’s lifetime. Disadvantages of Solar Tracking Systems No system is perfect. Here are the downsides you must consider before choosing a tracking setup for your solar energy system: Higher Initial Cost: Trackers add mechanical complexity (motors, sensors, actuators), stronger foundations, extra installation effort. That means more cost upfront compared to fixed solar panels. Increased Maintenance: Moving parts wear out, sensors may fail, motors may need servicing. For rooftop or commercial situations, this means additional operational cost. Structural and Space Constraints: On rooftops, especially commercial rooftops, the weight, movement envelope and wind load of a tracker may make it difficult or unsafe. Many trackers are more suited to ground-mount systems. Weather and Site Sensitivity: High winds, heavy snow, shading, uneven terrain can reduce the effectiveness of a tracking system or increase risk and cost. Diminishing Returns when Panels are Cheap: Since solar panels have become much cheaper, sometimes adding extra fixed panels may be more