Solar panels on your roof are easy to install, and require nearly no care. However, it’s not uncommon for stubborn dust, dirt and/or leaves to find their way onto your solar panels and soil the surface.
Although rain can wash away some of the dirt, relying on annual rainfall will not guarantee a clean and spotless solar panels. While the dirt doesn’t harm your panels, it can have a negative impact on a solar system’s performance. Therefore, in order to maximize your system’s performance, it is recommended that you clean your solar panels at least once a year.
So, how do we go about cleaning the solar panels?
Safety first: it is advisable that roof mounted panels should only been cleaned by an experienced solar panels cleaner. Fall protection should be used at all times during the cleaning process of any roof mounted system or ground mounted above 6 feet (2m). Also, protective gloves and eye goggles should be used at all times.
Solar panels are sturdy and made to endure harsh climates. But sudden pressure may damage the glass, frame or mounting system. Therefore, during the cleaning process, never attempt to climb on, stand and walk on modules or use a pressure sprayer of any kind for module glass cleaning! Avoid dropping or allowing any objects to fall on or remain on the module surface glass. Solar panels may break or detach from your roof, resulting in injury.
The best time to clean is the morning when the solar panels are still cool. Solar panels heat up during the day. If you apply lukewarm water on hot panels, the difference of water and panel temperature may shock and break the module glass. We recommend no more than 20° F (15° C) temperature difference between the water and the module.
Now that we have established safe cleaning practices, here are the four easy steps to clean your solar panels:
Step 1: Water the Panels
Using a standard ½ inch (1.5cm) flexible garden water hose with domestic water pressure, apply approximately 1-2 quarts (1-2 liters) of lukewarm, de-ionized (DI) water to the highest point of the module and allow the residual water to run down the entire module surface. Don’t use a pressure sprayer as this may force water to penetrate the glass and module frame sealant.
Step 2: Scrub the Panels
Using a soft, non-abrasive brush, with an extension pole handle, sweep the module in an up-and-down motion. This should remove any loose soiling from the module glass.
Step 3: Rinse
To rinse, apply approximately 1-2 quarts (1-2L) of lukewarm water to the highest point of the module to rinse off the loose soiling. If soiling remains on the panels, repeat the cleaning procedure.
Step 4: Remove residual water
Using a 24-inch rubber squeegee with plastic frame and extension pole handle, start at the top of the module glass and sweep the squeegee in one downward motion to remove any residual water from the module glass.
Clean solar panels will ensure that your solar system generates optimal electricity. With the right practices, cleaning solar panels should be easy and safe.