I get what you're saying, twice a year sounds reasonable. But honestly, I noticed a bigger difference than I expected when I started cleaning mine more regularly. We have some trees nearby, and even a thin layer of grime seemed to cut down efficiency noticeably. Maybe it's just my setup or location, but giving them a quick rinse every couple months actually boosted our output enough to notice on the bill... surprised me too.
That's interesting, I hadn't really thought about grime buildup affecting efficiency that noticeably. I usually stick to twice a year because it seemed like a good balance between effort and payoff, but now you've got me curious. We have some tall pines nearby, and I do notice pollen and sap residue sometimes... might be worth experimenting with a more frequent rinse to see if it makes a difference on our bill too. Thanks for sharing your experience, definitely food for thought.
I agree, grime buildup can definitely have a noticeable impact, especially if you're dealing with sap and pollen from pine trees. Sap residue is particularly stubborn—it's sticky and tends to attract even more dirt and dust over time, creating a layer that's harder to remove with just water. I've found that using a mild detergent solution (just a few drops of dish soap in water) helps break down the sap without damaging the panel surface. Just make sure to rinse thoroughly afterward to avoid leaving any soap residue behind.
Also, keep an eye on your inverter's output readings before and after cleaning. Tracking these numbers can give you concrete data on how much efficiency you're actually gaining from more frequent cleanings. In my case, I noticed about a 5-7% improvement after removing heavy pollen buildup last spring. It might not sound huge at first glance, but over several months, it definitely adds up on your electricity bill.
