2.6.2 Is paying for panel cleaning worth it?

We ran two field tests in Southern California, both at the end of a four-to-five month rainless stretch. Before-and-after photos and production data are available on request. Both tests showed the same result: production improved by ~10% the day after cleaning.

Conclusion:

• If you can clean the panels yourself, doing it every two months or so is clearly worthwhile. No special equipment — clean water and a soft mop is enough to remove dust and grime.
• If you're paying someone, ask yourself two things first: is your current production already meeting household demand? If yes, wait for the next rain — it will do the job for free. If you genuinely need more output, do the math: turn that 10% boost into dollars saved on the bill, and figure out how many months it takes to break even on the cleaning fee.

A roof that hasn't been cleaned in years is a special case — some grime is chemical and rain alone won't move it. If the price is reasonable, one deep clean is worth doing. Otherwise, run the numbers first.