Should solar panels be washed? Why is it worth it? How can it be done safely? In this article we will discuss ways to wash photovoltaic modules.
Solar panels produce energy from the sun. A clean panel surface is necessary for efficient operation. Accumulated dust and dirt on solar panels can cause energy losses of 7 to as much as 50%. So how should dirt be removed from solarmodules?
How to reduce dust settlement on solar panels?
Modules mounted on steep roofs, about 35-45 degrees, get much less dirty than modules mounted at a low angle.
It is worth investing in frameless modules from DAH Solar. Thanks to Full Screen technology that reduces sedimentation of dust and other contaminants, the module’s efficiency is up to 15% higher than traditional modules.
The benefits of the frameless design are many, described here: https://evolive.pl/produkt/modul-pv-dah-solar-dhm-60×10-fs-450w/
How to wash solar panels?
What to do when we don’t have Full Screen modules? Rain washes the modules of dust, but this is not enough. Dirt accumulates around the module frame and reduces their efficiency. There are ways to clean solar panels. These include methods that require manual cleaning, but also automated technologies.
Robots
Automated and semi-automated robots are used to clean modules installed in hard-to-reach places such as sheds, greenhouses or shed roofs. These work especially well for large installations in heavily dusty environments.
An interesting solution can be boasted by Ecoppia, which is deploying solar-powered robots. The autonomous robots clean the modules at night and use soft microfiber and air instead of water. They are clever devices programmed to also clean their own photovoltaic modules and recharge themselves when not in use.
Brushes and sponges (without soap)
PV maintenance companies have found that using demineralized water with a wheeled or vehicle-mounted brush allows them to clean the panels without soap, which would leave a residue that not only darkens the panels but also attracts dirt.
Homeowners can wash their solar panels by hand, using a garden hose and a soft sponge with no added cleaning agents.
Hand washing
Hand washing PV panels is the good old fashioned way! We can be helped by some instruments that make cleaning PV panels easier. There are many special brushes available on the market that rotate while removing dirt from the panel. We can also use brushes that are used to wash the windows of our cars. It is important to use brushes with soft bristles that will not scratch the surface of the panels. The more scratches on the surface of the module, the easier it is to get dirt. The best and safest agent for washing solar panels is demineralized water. Just like that! Without expensive cleaning agents! Demineralized water does not leave streaks and scale deposits. It is also important to remember to disconnect the installation from electricity during washing. Cleaning ground installations is usually not problematic, since the modules are within our reach. When washing installations on rooftops, care must be taken to ensure safety. We do not recommend washing installations located at height yourself.
Are these all the methods?
Of course not! Robots, waterless vibration or special coating solutions are just a few of the ways not mentioned in the article anyway. Such solutions are often costly and suitable for large farm installations, which are beyond the reach of those with small, home installations.
How to judge when it’s time to wash solar panels?
The most effective method is to see if we have any drops in system performance. There are companies working on ways to use advanced technology to monitor the condition of solar panels. Nevertheless, we can also evaluate the cleanliness of solar panels using the extremely popular “by eye” method.
Not everyone knows, but the cold winter air traps dirt closer to the ground. This problem does not exist in summer! What is the conclusion of this? After winter the modules will be contaminated, so in the spring they deserve a decent bath! We do not recommend washing modules in the summer, when they are hot. On cool spring days, but sunny, the modules also get hot, but the temperatures are not as high as in summer. We recommend washing the modules in the morning or early evening.
Sources
https://ratedpower.com/blog/clean-solar-panels/
https://www.revoltenergy.eu/blog/mycie-paneli-fotowoltaicznych-jak-robic-to-bezpiecznie