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Tracking systems increase the radiation received by a solar power system. This additional radiation turns into increased generation. Anybody who wants to maximize output from their solar panels should consider a tracking system.

As the Sun tracks its course through the seasons, the best solar panel operating angle will change. The more directly the solar panels can face the Sun, then the more beam radiation they will receive. Tracking systems, by adjusting this operating angle, help maximize this beam radiation received.

The amount of energy gained will depend on your location and the type of tracking system used. We looked up the solar energy tables for the state of Washington, and the difference between a fixed solar panel system and one with tracking was ~40% more in the summer months. The spring months showed a 25% increase, and winter about 10%.

One of the first tracking units one might consider is a manually adjustable one axis system. With a simple adjustment, the solar panels can be rotated on their horizontal axis to any angle. Each season will have an optimal tilt angle for maximizing the Sun. By adjusting our solar panels to that angle, we experienced summertime gains of 25% compared to a fixed solar panel installation. In the winter months this improvement was ~15%.

The next advancement in solar power tracking is automatic control of the one axis system. With the right set of equipment the solar panels can rotate with the daily path of the Sun. These systems provide strong increases throughout the year, sometimes as high as 45%.

The highest upgrade with solar power tracking is an actively controlled two axis system. The solar panels will rotate on their horizontal and vertical axes, which gives us two modes of adjustability. The cost and complexity of a two axis system makes them more of a specialty, but they are the most accurate units available for tracking the Sun.

Two axis tracking is often used with concentrating solar collection systems. Solar concentration is necessary when higher operating temperatures are desired. Thermal steam generators, pebble bed transfer systems, and modern Stirling engines are two such examples. If the concentrating collectors are not perfectly oriented with respect to the Sun, then their performance will greatly suffer. Concentrating solar collection designs, then, benefit most from the two axis systems.

Two axis systems are not so practical with photovoltaic solar panels. The tracking on the second axis provides only 5% additional energy when compared with the one axis system. For solar panel installations, then, it is more convenient to stay with a one axis system for most applications.

Solar power systems are developed for two primary purposes: heat and electricity. Adding a solar tracking system to your design is useful for either case. When it comes to making electricity with solar panels, a solar power tracking system will increase the production of electrical energy. When it comes to acquiring and storing thermal heat, it will help your system obtain higher temperatures.

If you desire an extra level of performance with your solar panels, a one axis tracking system is recommended. A manually adjustable system, such as Rotek, is a low cost solution and will provide modest gains. An actively controlled tracking system at moderate cost will provide very good gains. You will have to make a compromise between the upfront costs and desired performance when making this decision.