Solar photovoltaic systems are often presented as independent power producers that require little or no maintenance by the owner. While technology is remarkable, there is a simple thing to do to keep the solar panels work with maximum efficiency: cleaning!
Dirty solar panels (due to dirt, pollen, leaves, pine needles, smoke and ash, moss, bird droppings, insects, etc.) may experience performance up to 30% or smaller. Once dirt starts to accumulate on the surface of the panels, the sun’s rays are blocked and there has been no more energy. When cleaned, return to maximum effectiveness is immediate and easily measurable. I just read your meter before and after cleaning!
Some will say that the rain is sufficient to rinse the panels and keep them working effectively. This logic is faulty! Consider how often you need to wash your car, or your windows. They need washing occasionally, though exposed to rain, because rain is not always crystal clean and often only leave stains. The same applies to solar panels!
It may be tempting to approach a seemingly simple job yourself, but it is best left to a professional. It is easy to forget when you have before you, but your solar PV remains a dangerous electrical system components that can be damaged if improperly exposed to water and cleaning solutions. We should not just leave this job to a professional, but you should ensure that the professional in question is familiar with PV systems, preferably someone who also installed. Unlike Windows or gutters, solar panels produce electricity. The cleaning of the solar panels is simple in theory, but in practice are attached to a feeding mechanism, and can be very dangerous if approached correctly.
Most systems require only a good cleaning once a year. However, if you live in an area with a high concentration of dust (such as a farm or next to a baseball field), you probably need to be cleaned twice a year. The smaller the angle at which the panels are inclined, typically because they must be cleaned of dust and debris collected quickly without even rinsing by rainfall. Panels at an angle greater is the advantage of runoff from rain, but still need occasional cleaning because even the gusts of rain and leaves a thin film.