Preamble

Solar technology is gaining popularity in many applications such as Rooftop systems, power plants, pumping systems, street lighting systems, etc. One of the important aspects to be kept in mind is the continuous maintenance of the system.  An important point is the regular cleaning of solar panels. The solar panel has a toughened glass layer on top which is exposed to the sky and which faces dust deposition on it’s surface over time.  This dust results in the reduction of the energy generation from the solar system.  Hence it is very much advisable to regularly clean the solar panels so as to derive best results from it. The glass surface of the solar panel is a delicate surface and special care must be taken to ensure that the cleaning method used must be chosen so as to avoid damage or scratches to the surface of the solar panels.

Cleaning of solar panel surface

The decision of the technology to be used for solar module cleaning will depend on the type and capacity of the system.  For example, a small solar system (Eg. Having 10 solar modules) can be cleaned by just washing with water and wiping with a soft cloth.  However, the same method cannot be used for the bigger system using 100s of panels.  And for larger MW solar power plants the system and technology choice will further vary based on water availability.

In this article, we will discuss the ideal method for most rooftop and captive solar systems with about 50 to 1000 solar panels installed at the site. First of all the cleaning of solar panels require a period washing with water and mild scrubbing with a soft brush.

Given below is an image of such a brush.

Such systems have specially designed soft bristles on the brush so as to avoid any scratches and damage to the solar panel surface.  Also they usually have a water hose which delivers a continuous water stream to the bristles.

How many times should the solar panels be cleaned ?

The cleaning frequency depends on a number of factors.

The first criterion is the location and dustiness of the area.  For example areas which are very dusty must have a weekly cleaning schedule.  But for less dusty areas a fortnightly or monthly cleaning schedule is sufficient

Another criterion is the availability of water for cleaning the panels.  In case of sites where water supply is difficult it is not advisable to have a very high cleaning frequency due to the limited water availability.

Another point is the convenience of the users and access to the solar panel installation area.  A slight compromise on the cleaning frequency is acceptable in case of limited manpower availability or other typical site problems.

Conclusion 

It is important to ensure regular cleaning of the solar panel surface so as to derive best energy output from your solar system.   Of course the cleaning frequency and necessity changes depending on the type of system and convenience of the owner.

Also, very important point to keep in mind is making use of the right cleaning solution to ensure the solar panel surface does not get damaged in the process.  Otherwise it is not possible to remove the scratches once the solar panel is damaged.Although regular cleaning of the solar panels is necessary to achieve best energy output from the solar panels , the solar system will continue to operate at a major percentage of it’s capacity even without cleaning.