Cleaning solar panels. Does it pay off?
To make our homes more sustainable, an increasing number of Dutch people are investing in solar panels. You purchase the panels and have them installed on your roof. It's a significant purchase and a task to get them up on the roof, but once they're there, you can generate energy with peace of mind. However... what do you do when your panels suddenly become covered in bird droppings or tree debris?
Persistent dirt can reduce the efficiency of your solar panels. But how much exactly, and how necessary is it to clean off that bird droppings from your panel?
Up to 10% loss in efficiency
According to independent comparison platform Pricewise, this loss in efficiency can reach up to ten percent if the panels are dirty, and the solar panels can even be damaged by the aggressive composition of bird droppings.
Energy specialist Tomas Bleker from Pricewise also mentions that a rain shower is usually not enough to wash away the dirt. "Rain does remove most of the dust, but bird droppings are stubborn and tend to stick. The result? Loss in efficiency."
How to keep your solar panels clean
According to Pricewise, it is advisable to clean your solar panels regularly, and according to Bleker, even once a year. If you want to take matters into your own hands and give your panels a cleaning, it is wise to consider the following:
- Avoid using a high-pressure sprayer as it can damage the glass and cables of the panels.
- The water used for cleaning should not contain calcium. Instead, use osmosis water, which is demineralized water in its purest form and free of calcium. This type of water is available at various cleaning stores.
- Additionally, it's better not to use any cleaning agents to clean the panels, as they can affect the energy generation. Only (osmosis) water is sufficient for a thorough cleaning.
- Use a soft sponge or cloth and avoid using abrasive scrubbers to remove bird droppings from your solar panels. Scrubbing can cause scratches and damage the panels.
Best time of the year
It is recommended to clean your solar panels in the spring, ideally before April, as the panels generate the most energy between April and October. The cleaner the panels are, the better they can perform during those months.
Furthermore, it is not advisable to clean the solar panels on an extremely hot and sunny day, as the panels can become very hot and may be damaged by water afterward. The significant temperature difference could even cause cracks in the panels.