How often should panels be cleaned?

A common question I get from customers is, how often should panels be cleaned? In general, for homes in mild climates, manufacturers recommend once every 6 month to a year. In dusty, dry, or coastal areas, which is basically most of Southern California, manufacturers recommend once every 3-4 months. Tesla Solar makes this recommendation on their website:

To help maintain system performance, it is recommended to routinely have your Solar Roof cleaned by a professional cleaning service. We do not recommend that Solar Roof owners step onto their roof so as to avoid danger of slipping, falling and injuring themselves.

Your professional cleaner should provide the service as they do with any roof, directing the flow of water from a power washer downwards off of the roof to avoid directly spraying the front edge of your tiles, as well as in between your tiles. For more challenging areas, such as where dust or debris has built up, they should use a telescoping soft brush (similarly used for washing a vehicle) to gently wipe your roof surface. Avoid using detergents, abrasives, solvents or other types of cleaning products on your Solar Roof.

At Interstellar Solar Cleaners, we go one step further. We give a detailed photo report after each cleaning, so you can see and determine for yourself what cleaning interval you'll be satisfied with. Similar to your vehicle, the important thing is that the cleaning is done regularly, not just for efficiency, but also to control oxidation and protect the outer coating on each panel.

As the Tesla quote mentions, we never use any detergents, chemicals, or hard bristles to speed up the cleaning, rather we use the softest boar's hair bristles and thoroughly soak each panel to loosen up the dirt layer, one panel at a time. It is more work and more time-consuming, but it is the gentlest approach, one that most preserves the panel coating for the best long term care. That's what makes Interstellar cleaning "out of this world."