Cleaning solar panels

[Robert1234]

i find it interesting that you would rather get advice from someone with no experience than a professional who cleans panels for a living

Advice from someone with no experience??? WTF Dude... You really think the professionals on this forum need a phd in window cleaning to know that it's easier to look out a clean window than a dirty one? Gimme a break.

[JC1]

Clean panels are more productive - not too hard for most to understand. Trying to say some firm has something special is a bit overboard.

depends on the firm, right?

cleaning with soaps will leave the panels coated in a film, reducing their efficiency. This film my not be visible to the necked eye but it is there. I called RainX asking about applying their product to help protect panels and they strongly advised against it due to the film left behind. I also contacted a few panel manufactures asking about cleaning and they advise against soaps, rainX and garden hose (in hard water areas) due to residues left behind.

[russ]

depends on the firm, right?

cleaning with soaps will leave the panels coated in a film, reducing their efficiency. This film my not be visible to the necked eye but it is there. I called RainX asking about applying their product to help protect panels and they strongly advised against it due to the film left behind. I also contacted a few panel manufactures asking about cleaning and they advise against soaps, rainX and garden hose (in hard water areas) due to residues left behind.

Same thing you read here. We are talking about "Tony with a pickup" type of contractors for the most part with the cleaning.

You need to use soft water and not leave a residue on the glass. I am curious what Rain-x will have for an official reply.

[JC1]

Advice from someone with no experience??? WTF Dude... You really think the professionals on this forum need a phd in window cleaning to know that it's easier to look out a clean window than a dirty one? Gimme a break.

Who are the professionals on this forum you are talking about?

Having a PHD does not make someone a professional in the solar panel cleaning business

A clean window is much different than a clean solar panel - We can put rainX and many other cleaning products on our windows and still see through them without any issues. Any film left on a solar panel will have a negative affect on the ability of that panel to produce electricity, whether or not it can be seen with the naked eye.

[JC1]

I am curious what Rain-x will have for an official reply.

they have a "contact us" button on their page, give them a call and ask, I did.

[JC1]

Same thing you read here. We are talking about "Tony with a pickup" type of contractors for the most part with the cleaning.

You need to use soft water and not leave a residue on the glass.

Soft water can/will leave a residue, you need pure water if you don't want to leave anything behind

[russ]

they have a "contact us" button on their page, give them a call and ask, I did.

Calling from Turkey they might not appreciate - I would also like to see the reply in an email I can post here.

[SunEagle]

Soft water can/will leave a residue, you need pure water if you don't want to leave anything behind

I guess you mean either purified or distilled water. And a very soft brush to help clear the dirt.

[russ]

Soft water can/will leave a residue, you need pure water if you don't want to leave anything behind

Sorry but what you say makes no sense - just stop at leaves no residue.

[Robert1234]

Exactly what wavelength(s) of light do you think are being impeded by each of the cleaning technologies you believe you are superior to?

[JC1]

I guess you mean either purified or distilled water. And a very soft brush to help clear the dirt.

pure water, zero TDS

[Volusiano]

I can easily see how one person can interpret soft water to be one thing, but another person can think of it as something else.

To clarify the term soft water, it can mean 2 things:

1. Unconditioned water from tap with very low TDS reading (very rare).

2. Conditioned water after tap to soften up the water, as coming out of the water softener. In this case, the water is "soft" in terms of being easier to help with lathering and less soap use. But this water still contains impurities. It basically exchanges mineral ions with the salt ions imbedded inside the water softener's resins, so now it has less mineral ions but full of salt ions. This water will leave salt spots behind when dry.

Usually pure water with zero or very low TDS for water fed pole window washing or solar panel washing is produced by filtering the tap water through an RO/DI system.

[Volusiano]

I guess you mean either purified or distilled water. And a very soft brush to help clear the dirt.

Specific to using a very soft brush to help clear the dirt, in general it makes sense for window washing or car washing, but for solar panel washing, a very soft brush may be problematic in a water fed pole situation with pure water. Here's why:

The technique for normal window washing is to use a brush to agitate the dirt into solution, then lift up the pole away from the glass to allow the jets of water to rinse the glass. For windows, they're vertical so the pole is fairly vertical so it's easy to lift up the pole away from the glass to rinse. For solar panels, they lie more flat on the roof, so depending on your reach, it may be a lot harder to try to lift up the brush head to do the rinse if the pole is fairly horizontal.

If you use a very soft brush and cannot lift the brush/pole away from the glass for rinsing, the weight of the brush and pole can collapse the brush on the panel, not allowing the dirt to escape the brush. In that situation, you'll need a firmer brush, preferably a dual-trim type (longer bristles on the outside and shorter bristles on the inside) which is firm enough to stand straight under the weight and allow the water from the jets to clear out the dirt from under the brush. This firmer brush is still soft enough to not damage the glass, but firm enough to not collapse on its weight and the pole's weight.

[JC1]

Specific to using a very soft brush to help clear the dirt, in general it makes sense for window washing or car washing, but for solar panel washing, a very soft brush may be problematic in a water fed pole situation with pure water. Here's why:

The technique for normal window washing is to use a brush to agitate the dirt into solution, then lift up the pole away from the glass to allow the jets of water to rinse the glass. For windows, they're vertical so the pole is fairly vertical so it's easy to lift up the pole away from the glass to rinse. For solar panels, they lie more flat on the roof, so depending on your reach, it may be a lot harder to try to lift up the brush head to do the rinse if the pole is fairly horizontal.

If you use a very soft brush and cannot lift the brush/pole away from the glass for rinsing, the weight of the brush and pole can collapse the brush on the panel, not allowing the dirt to escape the brush. In that situation, you'll need a firmer brush, preferably a dual-trim type (longer bristles on the outside and shorter bristles on the inside) which is firm enough to stand straight under the weight and allow the water from the jets to clear out the dirt from under the brush. This firmer brush is still soft enough to not damage the glass, but firm enough to not collapse on its weight and the pole's weight.

what are your thoughts on a hog hair brush?

[Mike90250]

... For solar panels, they lie more flat on the roof, so depending on your reach, it may be a lot harder to try to lift up the brush head to do the rinse if the pole is fairly horizontal.

If you use a very soft brush and cannot lift the brush/pole away from the glass for rinsing, the weight of the brush and pole can collapse the brush on the panel, not allowing the dirt to escape the brush. ....

I like where the operator gets the heavy pole & brush about 10" up, and something gives way, and it smashes down on the panel.