How Often Should Solar Panels Be Cleaned in Southern California?
A practical guide to solar cleaning cadence in Southern California, by location, environment, and system size. Real recommendations from a SoCal cleaning crew.
Southern California's combination of low rainfall and year-round sun makes solar cleaning frequency a real decision, not a generic 'every few years' answer. Here's how we actually recommend cadence after thousands of cleanings.
The default: twice a year
Dirt and debris can block sunlight, but the effect varies with the amount of buildup, panel tilt, rainfall, shading, and equipment condition. We don't have a verified typical loss figure for San Diego homes. Compare monitoring data under similar weather conditions before and after cleaning rather than expecting a fixed percentage gain.
When to go quarterly
Step up to quarterly if any of the following apply: you're within ~2 miles of the coast, your home is along a freeway corridor, you're near an active construction site or open dirt, you have heavy tree cover, or you've noticed visible bird activity above the array.
When once a year is enough
Annual cleaning works for inland homes with little debris, minimal bird activity, and no nearby construction. It's a minority of homes, but if you fit the profile, you can save by going annual.