Solar panel cleaning marketing question

I want to start offering solar panel cleaning, I see many different places that have solar panels be it a business, home, commercial area.

I’ve done solar panel cleaning in the past and I understand the need for upkeep on these systems but I want to have some sort of information in a marketing piece that I can walk in and hand to a prospect as well as my card.

Do any of you guys do this? If so, do you have like “5 reasons to keep your solar array clean” type literature. I don’t want a full brochure of info, but something that I could do on an oversized post card and walk in to these prospects, introduce myself and what I’m offering then leave them with this information postcard and a business card.

I’m in no rush and I want to do this properly and professionally when it comes to educating the potential customer.

Mike Radzik

Pro Window Cleaning

Sent from my iPhone using Window Cleaning Resource

Actually, I’m going to be meeting with one of our solar panel companies this week or next. I talked with him on monday and he says there’s some trade articles that I could use. He was going get those for me and I’ll scan them in and share them for anyone interested. He was VERY interested in partnering up with me: he’d get the commercial clients (and government clients since he’s disabled vet with no-bid status) and I’d clean them. So I’m pretty excited about that.

He’s also has access to a phd at one of the labs who is obsessive compulsive about panels and he might be willing to write something up.

As a solar homeowner myself, I think solar marketing should be all about ROI, plus maybe a few intangible facts. If you can crunch some typical numbers through to convince customers that they will save $ (or even just break even) by investing in having their solar panels cleaned, then you may be able to make the sale.

Start by using the PVWatts tool online (free) and plug in some typical numbers for your area, with some typical size systems, like 5kw, 7kw, using 250W panels, put in the typical roof pitch and orientation (south or west or east), use a derate factor of 0.85, and let PVWatts estimate the system solar production for each month in your area. Then check out the typical utility rate for your area and multiply this by the monthly production to figure out the monthly value of the produced energy. You can play around with peak rate if you want if customer is on Time of Use plan. Or just stick with basic plan rate for simplicity.

Then use either 5%-10% (I’d recommend 5%) of this as the possibly production loss (hence value loss) due to dirty panels. Divide this by the number of panels and you’ll have the cost per panel due to production loss. Assuming that the panels stay dirty like that for 3 months, multiply this by 3 to get the 3 month cost per panel of production loss due to dirty panels. Then maybe you can use this as a basis for your fee. This way, customer has an idea of how much ROI they can get for their investment in having their solar panels clean.

You can also point out some other intangible facts like just hosing off the panels is not the same as cleaning (would you just hose off your car from afar and call that clean?). Sometimes even rain does not get the panels completely clean either, depending on how hard it rains and how much pollutant is in the rain. At least a once-a-year thorough cleaning with a brush is good for making sure stains from hard water or harsh environment don’t accumulate on the panels which makes it harder to scrub off years after years.

Obviously you can’t put everything on a post card. Maybe just some key facts on the ROI to get them hooked enough to go on to your website for more details.

This is exactly the info I was looking for in the other thread about solar panels.

2013 World Series Champion
Boston Red Sox

there needs to be some before and after readings that make a difference

unfortunately, I’ve actually had a customer with 60 panels that were filthy and he sent me the output chart for the month and it made no difference, go figure (june)

Yeah, it’s very subjective. There’s too many variables that can affect the accuracy of before and after readings. The weather sure varies and if you don’t get the same good weather after the cleaning as before, then it will not show any difference and they blame it on 0 ROI. If you get better weather after the cleaning, then people may think it’s the cleaning that boost up their production significantly but it may be mostly due to better weather and they claim significant ROI. You can only do that kind of before and after measurement in a controlled environment or else it’s only a rough guess and it can swing either way, depending on the insolation you get before and after cleaning.

It also depends on the level of dirtiness of the panels. Slightly dirty panels will have less loss than severely dirty panels. But how do you measure the dirtiness of your panels? There’s not even a metric for that…

If you can find some credible figure online to support the average production loss due to an average level of dirtiness in a controlled environment that you can quote, then that would help. Otherwise, it’s just a swag. But I’m sure dirty panels will produce less than clean panels for sure, that’s common sense. The question is by how much? That’s why something like 10% is not a credible figure. 5% may be more believable. And that’s why you don’t really want to do before/after measurement in an uncontrollable environment.

The better approach is to use the universally accepted PVWatts production estimate that can be fine tuned to your area’s average weather patterns collected over the years, along with parameters like panel pitch and orientation, to get a good estimate on monthly production and take off 5% from that as the production loss. If the panels are severely dirty, then maybe bump it up to 6, 7, 8, 9 or 10%. It’s your guess or let the customer guess. Or just stick with 5% no matter what.

If the customer insists on before and after reading, then it has to be on 2 VERY similar days, where there’s NO cloud at all, same temperature, same time frame (within a few days of each other) so it’s the same sunrise and sunset time and same sun path. But taking the output chart for the whole month is too inaccurate because the month before can have much different weather pattern than the month after.

And you also need to make sure to point out the intangible ROIs as well -> cleaner panels look better especially if they’re on the front roof area of the house. And like I said, even if they don’t want to do it every 3 months or 6 months, a once a year thorough scrubbing is good to get rid of any accumulated stains from hard water or the environment that won’t come off simply due to a rain storm.

but they were FILTHY and there wasnt even a bump, actually a decline on the next cloudy day, but with 15 days after that, all the bars were in similar range

I’ve got another customer who has a live output app and Im going to ask him to check before and after and do it in mid day

I calculated 5% on one job and it didn’t even come out ahead for the cost of service

I sure wish there was a slam dunk positive difference and a difference vs hose off with tap water too, wouldnt that be great

I’ve had clients tell me they’ve gotten 30% bumps…we got great dirt here…

That only goes to show how inaccurate the before and after measurement can be if you can’t have a tightly controlled the environment with everything else being equal. One person didn’t even see a bump while somebody else sees a 30% bump.

If it’s any help, [B][I][U]here’s a link[/U][/I][/B] about panel cleaning and a couple of homeowners (one in San Diego, Bando; and another in AZ, Ian S) reported about 6% improvement in their production after cleaning. In Bando’s case, the rain cleaned her panels. In Ian’s case, he cleaned the panels himself. I think they did use before and after cleaning measurements, too, so I don’t know how accurate their number is, but at least they came up with similar numbers. Also, as homeowners who carefully planned their measurements, I hope they tried to keep tight control of their data to weed out the variables that could have affected the accuracy of their numbers.

For sure there is some research available on this where panels have been used next to each other in same condition, one filthy and one cleaned. That would make a good comparison.
Would it make also any difference to apply a water repellent coating to the panel after cleaning?
Interesting subject, like it.
Krassen verwijderen door glas polijsten

You read my mind. But considering the extreme conditions on the surface of the panels, what would the longevity of said application be? again, variables.
This link is to a study as I mentioned: a well conditioned test of cleaned and non-cleaned oanels in parallel. Study says that improvement varies from 2.2% up to 12%. It depended on how dirty panels were. Study was conducted by an indipendent Belgian test institute.
Sorry that text is in Dutch, but you van find the numbers in the text.
Krassen verwijderen door glas polijsten

I contacted RainX and they said their product, although transparent, it [B][U]will reduce[/U][/B] the effectiveness of the panels

I find it very interesting that some of you are having this issue. Not sure how solar is set up in the US, but in Aust we have meter boxes that give an immediate reading of solar input. So far, every clean I’ve done has seen between 10 - 30% immediate increase. I do a before and after reading with the owner, and they are always surprised at the difference, and make a future booking.
This week I had 24 panel home reading 2300kw before, 3210kw after; 18 panel - 1650/2390; 8 panel - 810/1100

how wold you describe the dirt level?

and the length of time that customers had let go by before previous service?

totally coated and brown looking surface
maintenance type clean


They have all been total covered, and the panels are always a sandy grey color.
On first pass the wash-off is consistently a watery-coffee color, although homes under the flight path have a black wash-off.
It normally takes 3-5 passes to get a clear wash-off.
Panels 6 months old compared to 2 years old are not much different that Ive seen. Maybe the dust/dirt build up has a critical mass, so to speak. I dunno, the chemistry and physics of particle layering on glass aint my thing - I just wash it away!!.
All my customers have been first timers, so it will be interesting to see what its like on return.
I have new panels up, so will be keeping track myself of results too.

that’s very dirty all right!

thanks for the details

The problem with comparing PV production data is that there are so many variables. Sure there is the amount of insolation (exposure to the sun) which is affected by daily variables like sun angle at that time of year, atmospheric effects from air quality and cloud cover. But you also have to look at temperature as high temps will derate your array. Every one of these can mean that a cleaning will show 0 effect or even a negative effect within the next month.
If you really want to compare apples to apples, you have to track a whole year without cleaning and then a year with cleaning but then make sure that the average daily temperature and precipitation are the same for both years. Of course, that doesn’t help with your marketing plan…
What every customer should know is that a cleaning is part of almost every manufacturer’s simple maintenance plan (which can be part of their warranty requirements). Using a professional to clean your panels also means that you have someone experienced looking and inspecting your system as well. The panels are also getting a better quality clean that will be very important in the long term over just spraying everything with a garden hose. Especially in areas with hard water, you are saving them the hassle of difficult to remove if not permanent mineral deposits. You also are agitating and removing stuck on contaminants like bird droppings which block access to the sun. If large enough, a single bird doo can take out 1/3 of a module’s production capability.