Why should solar panels be cleaned ?

If you have a solar panel installation on your property, be it your home or work, it is essential the panels are regularly cleaned in order to maintain optimum performance. Dirt and dust can limit the amount of light reaching the sensitive photovoltaic cells in each panel and therefore reducing the amount of electricity generated.


Just like the windows in your home or office, external factors such as air pollution, motor vehicle exhaust emissions, bird droppings and even leaves can lead to your panels quickly deteriorating causing inefficiencies. Surprisingly even rain does not provide an adequate cleaning solution to dirty solar panels due to the amount of dust and chemical particles in the water droplets, when the rain water evaporates it leaves behind a dusty, streaky residue which also requires cleaning on a regular basis.


When your solar panels are first installed the rates of performance are based on the panels being in a brand new condition. Many people don’t consider or are not informed about the vital need for cleaning throughout the lifetime of the panels. All manufacturers will warranty their solar panels for a number of years based on regular maintenance and servicing  and it is often a condition of the solar panel warranty that the panels are kept clean. If you can’t prove to the manufacturer that the panels have been regularly cleaned it may invalidate the warranty – its always best to check the terms and conditions.


The efficiency losses over a period of months can vary depending on geographical location for instance an installation in a built up industrial area may need more regular attention due to the levels of dust and pollution expelled by neighbouring factors.

What’s the best way to clean solar panels ?

Many window cleaners will attempt to clean your roof top solar panels from the ground using telescopic long reach poles with a cleaning brush on the end. These poles and brushes add enormous and unnecessary weight onto your solar panel array whilst cleaning and can cause unrepairable damage to your panels (see picture below).  Another point to consider is how effective are my panels being cleaned when the window cleaner is stood more than 10 metres away – can they really see what needs to be cleaned ? Access platforms should be used to clean at an appropriate height avoiding any risk of damage to your equipment or property. 

How often should solar panels be cleaned?

 As a guide we recommend:

Home Solar installations - once every six months*

Commercial Solar installations - once every three months*

Solar Farm installations – once every four months*


*dependant on geographical and environmental conditions