https://www.reddit.com/r/solar/comments/134z34f/what_does_everyone_do_to_clean_their_solar_panels/
What does everyone do to clean their solar panels? : r/solar
May 1, 2023 ... First, use a high pressure hose spray nozzle to rinse as much dirt, grime, bird droppings, etc off of the solar panels, then use a mild dish soap.