If you use solar panels on your home to provide electricity or heat your water, you probably have wondered if you need to change the angle of your panel during the year to make the most of the sunlight. The answer to that is a resounding yes. Optimizing the solar panels enables you to get the most from them, but your solar panels will still work even on cloudy days since the panels do not depend on direct sunlight.
Understand the Types of Sunlight
Before optimizing your solar panels, you should understand the three types of sunlight that hit your panels. The first is direct irradiation, which occurs when the sunlight hits the solar panel directly. Diffuse irradiation happens when the sky is cloudy and no direct sunlight reaches the panels. Finally, your solar panels can benefit from reflected light. Buildings and even trees can reflect light to the solar panels. This is a phenomenon we see frequently in snowy conditions.
Set the Panel Angles
Although your panels will still work without adjustments, you’ll optimize them by changing the angle to give you the most energy. You’ll need to make four different adjustments during the year. Unless you have an automatic tracker, you’ll need to climb up on the roof to make adjustments. Use a protractor to establish the right angles. The generally accepted theory for optimization is as follows:
- At the beginning of February switch the panel so the angle is the same as your latitude. Thus if your latitude is 49 degrees, set the solar panel at the same angle to be most effective.
- Three months later, at the start of May, change the angle to your latitude minus 15 degrees. At 49 degrees latitude that would be 34 degrees.
- At the beginning of August move the panel back so the angle is the same as your latitude.
- Once November arrives, reset the panel to your latitude plus 15 degrees. For 49 degrees latitude, this would be 64 degrees.
If you want to be more exact, you need to discover exactly how the sun moves across the sky where you live. You can accomplish this with an Internet search for a solar radiation map. The map will show you how much sun any particular location receives at each time of the year.
Use an Automatic Tracker (Optional)
You can readily purchase automatic solar trackers. With these, your solar panels are put on a pathfinder that follows the sun across the sky. They are expensive, and you will need a professional installation unless you’re very adept.
Trackers do make a significant difference. Results have shown an increase in power of 35 percent in the summer and 15 percent in the winter. Several different manufacturers produce these units, which all give around the same level of improvement.
Use Reflected Light
In winter, when the sun is low, you can increase the amount of reflected light on your solar panels by mounting mirrors on the sides of the panels. Although the method has not been scientifically proven, a number of solar panel users do this and have been pleased by the results.