[Aurornis]

Washing solar panels is one of the current popular business ideas on social media. It’s an easy pivot for anyone who already has some experience with much harder home repair handiwork involving a ladder.

The reason it’s popular is because most people don’t understand the economics at all. Someone can go door-to-door in a neighborhood offering to clean solar panels and making huge claims about improving efficiency so much that you can’t afford not to do it.

Homeowners who invested $30K in solar panels think of a $300-600 charge as an easy choice to keep their investment producing money.

My parents had someone going around their neighborhood trying to charge $50/panel for cleaning. They didn’t even climb a ladder. They sprayed washing solution from the ground. Most neighbors declined, but you could see the guy spraying down a couple roofs.

Easy way to clear $1000+ per day for knocking on some doors and pointing a hose at a couple rooftops, at least until the public figures out the scam.

[dredmorbius]

Many years ago (and possibly still today) there were firms offering refrigerator-cleaning services. Brushing off the condenser (external) coils.

Yes, that may save you a bit of energy. No, not that much, and overall the financial savings are a small fraction of the service's charge.

A friend worked in energy conservation at the time and actually studied the impact of cleaning coils on refrigerators as part of a recycling programme (so: measuring pre- and post-cleaning power consumption on units which had been in use, most for quite some time). The net results, over hundreds (if not more) units: to little difference to detect statistically.

If you're doing the work yourself or don't have to pay for it: possibly worthwhile for peace of mind if nothing else. Paying someone else? No.

I suspect a similar situation for solar panels.

[ChiperSoft]

Where I live we don't get much rain, have a lot of dust, and I have a pine tree next to my house that sheds sap onto the panels. That means they get pretty filthy over a year. I pay a guy $150 once a year to come clean them off.

The gains are marginal, I'd have to do more research than I feel like doing to get hard numbers weighted against weather conditions, but I'd guesstimate around 300-400kWh more output per month.

SDGE gives me $0.3-0.5 per kWh during solar peak, so I'm breaking even after one month, and it makes the house look nicer, so I'd call that a win.

[rsynnott]

Funnily enough, there was a thread a while ago here where people were fixated on the idea that you had to wash solar panels, and thus proponents are underestimating maintenance costs. I had wondered where that idea had come from, as I thought it was fairly well understood that even quite dirty panels once much of an efficiency drop…

[jhot]

I asked a friend with a window cleaning business and they charge about $10 a panel. At that rate I'm tempted to try it but I'm not sure if it's even worth that.

[xandrius]

$10/panel to go on top of a roof with the possibility of braking s leg or worse? I'll keep my coding job from my couch :O

[JamesSwift]

Its an easy value add for a pressure-wash / soft-wash business

[benj111]

Are window cleaners not a thing in your neck of the woods?