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How to clean solar panels?

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I noticed a few days ago that mine were covered with pollen. I hosed them off, and it removed some of the pollen but not all of it. I've since ordered a 24' solar washing tool from EquipMaxx so I can do a better job. The water running off the panels the first time I hosed them looked like running mustard. I got a couple of hundred watts increase in output afterwards. (PS... the same tool through Amazon is $40 more!)
If you did this in the daytime, sun shining, panel cooling off will give you that extra energy. ;)
 
I think what I'm going to do as a test is to clean 2 of my panels, then look at the numbers for the following day and compare the output of those 2 panels to the panels adjacent to them to see what the production difference is.
I don't have Tesla panels, just a Tesla Powerwall2. I've got panels with micro-inverters and can see the production of each panel on my Enphase system.
Be careful with your calculations as you can see that day how close the energy output is between panels but were they the same the day before on a similarly sunny day? Or the day after you clean the panel? One-time snippet may not tell you much. Was it the same outside or panel temperatures? Don't look at the just washed panel as it gets colder from the washing, more energy production.
 
I noticed a few days ago that mine were covered with pollen. I hosed them off, and it removed some of the pollen but not all of it. I've since ordered a 24' solar washing tool from EquipMaxx so I can do a better job. The water running off the panels the first time I hosed them looked like running mustard. I got a couple of hundred watts increase in output afterwards. (PS... the same tool through Amazon is $40 more!)
Please share your actual experience after using the special tool. I was contemplating with buying a $200 tool or just a cheap regular washing tool with a separate hose. I went with the latter but haven't cleaned the panels yet.
 
If you did this in the daytime, sun shining, panel cooling off will give you that extra energy. ;)
Meh. When I first looked at the panels, they looked like i'd painted them yellow. I tried hosing them off, and the result was the first picture. I used the brush I bought on them today and as you can see, they're much cleaner.

IMG_4844.jpegIMG_4850.jpegIMG_4849.jpeg
 
There are filter cartridges that screw onto your hose. They’re for rinsing cars. Wonder if those would work for solar panel cleaning with hard water?
In principle, yes, in practice, not so much. The screw in cartridges are just small demineralization filters filled with deionizing resins. They are great for "polishing" low TDS water (Pacific Northwest or New England water sources generally), to remove the last little bit of dissolved minerals, but they don't have enough capacity for those who have hard water, even if it is softened. Hard water users need to go hard water to softened water to reverse osmosis (to lower the total amount of dissolved ions) to a demineralization cartridge. Most people don't have a large enough RO unit, I.e. a unit that is measured in gallons per minute, rather than the more typical gallons per day.

For me, it is cheaper for me to hire someone who brings their water and their monster demineralization filter than put in a filter system large enough to have the capacity to wash the panels. Definitely a YMMV, depending on how bad your water is to begin with. I have friends who were required to RO their entire household water as a requirement of their building permit due to water quality issues. The filter sits in its own 14x14'14' outbuilding.

All the best,

BG
 
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