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How to maintain a solar panel
Purchase a solar panels cleaning kit.
It should contain a liquid soap, a wiper, a small brush and in some cases another brush with a longer handle. In many ways, these items are similar to what you use to clean your car, so if you cannot purchase a cleaning kit that is specifically designed for cleaning solar panels then you can substitute it with your car cleaning equipment instead.
Mix the soap with water in a bucket. The amount that needs to be mixed should be mentioned on the bottle of liquid soap.