Does anyone use anything like Rain-X on their panels?

[pamalot]

So, I went up there and took a look this morning. The panel that has the Rain-X on looks noticeably cleaner than the other panels. However, I came to the conclusion that it's probably because I cleaned that panel before I put the Rain-X on and I didn't clean the other panels. So I've just re-set the whole experiment again and washed ALL panels clean this time. I'll go back up there in a month and see if I can see a difference.

[J.P.M.]

So, I went up there and took a look this morning. The panel that has the Rain-X on looks noticeably cleaner than the other panels. However, I came to the conclusion that it's probably because I cleaned that panel before I put the Rain-X on and I didn't clean the other panels. So I've just re-set the whole experiment again and washed ALL panels clean this time. I'll go back up there in a month and see if I can see a difference.

Thanx for the info. I'll be interested to see what happens. I'd suggest keeping in mind that the human eye is not the best tool to gauge the effects of dirt and its effects on solar equipment performance.

[pamalot]

Yesterday I ventured back up to take a look. It's been at least a month since I cleaned all panels and re-applied the Rain-X to just one of them. What I could see if that there is a marginal difference. The Rain-X panel seemed to have a little less rain residue/dust/dirt on it. It's a small but noticeable difference which I think would get bigger with time. How much difference it would make to the efficiency of the panels I have no idea. But as I can't see any immediate downside I took the opportunity to put Rain-X on all the panels. I'll let you know if I experience anything negative. But so far my conclusion is that the Rain-X probably helps, but in a very small way.

[solarix]

I tried Rain-X a few years ago just like you. Had some left over from a previous life so always being curious.....
My conclusion (without any objective tests) was that it was detrimental if anything. Actually seemed to make the glass a little sticky so stayed dustier. The difference with PV panels is you don't have a wiper to do the cleaning. Also suppose the Rain-X might interfere with the anit-reflective coating on the glass.

[russ]

You can get a cheap ($200-ish) thermal camera attachment for a smartphone. Not as accurate or fancy as a dedicated unit, but good enough to find hot spots on your panel. Plus way fun to play with. The model I bought is called Seek Thermal, and is readily available on Amazon.

Thermal cameras in the hands of a newbie give useless temperatures. They provide more useless data than possibly any other measuring device on the market. Emissivity is the key part and most have no idea what the word means.

[SunEagle]

Yesterday I ventured back up to take a look. It's been at least a month since I cleaned all panels and re-applied the Rain-X to just one of them. What I could see if that there is a marginal difference. The Rain-X panel seemed to have a little less rain residue/dust/dirt on it. It's a small but noticeable difference which I think would get bigger with time. How much difference it would make to the efficiency of the panels I have no idea. But as I can't see any immediate downside I took the opportunity to put Rain-X on all the panels. I'll let you know if I experience anything negative. But so far my conclusion is that the Rain-X probably helps, but in a very small way.

Thanks for experimenting with the Rain-X.

Just keep an eye on any gasketing or sealant around the panel frame to see if there is any breakdown and water intrusion due to a chemical reaction.

[russ]

But so far my conclusion is that the Rain-X probably helps, but in a very small way.

Boy but that is one scientific conclusion! Peer reviewed by three ants and a fly?

[Dawnweaver]

I suppose a hypothesis has to start with a single test case before a larger scale and more scientific experiment can be performed. Keep us updated with your experience.

[russ]

I suppose a hypothesis has to start with a single test case before a larger scale and more scientific experiment can be performed. Keep us updated with your experience.

Dawn - Something like this would have to be done under very controlled conditions - which are very difficult to do out of doors - not to mention who has the necessary equipment starting with a pyranometer.

While results may be of general interest they are pretty much meaningless.