Cleaning solar panels effectively

aminaelis

Hello everyone,

I am totally new to this whole solar panel concept. We just moved to a house with solar water heater and since it hasn't been lived in for quite some time, we have a lot of things to fix, clean and so on. What is the best way to clean solar panels? Ours are dusty and also there are many pipes and wires around them, some in pretty bad shape but our landlord said it's fine.

Is there any effective and gentle way to clean solar panels? 

I will look forward to reading your suggestions . 

mcgivor

Wash in the morning or late afternoon using plain water and a sponge squeegee seems to work in most cases, be generous with the water to float the dirt off. Hard water can leave deposits but generally less than the dirt it replaces, that's the method I use, water then squeegee dry, others may have differing opinions and suggestions.

Solray

Use a window cleaning wand and water with a little glass cleaner such as is used for automobile washer fluid reservoirs.

Estragon

These may be solar thermal, not pv. If so, they may be made of a type of rubber that may be damaged by certain chemicals. A windshield cleaner, for example, may contain an anti-freeze that can cause problems with some types of rubber.

I would use a soft brush or duster to get most of it off, then hose down with plain water. If needed a little gentle detergent for tough spots and a freshwater rinse.

Solray

I wouldn't leave anything on the panels after cleaning even if it's just water. A lot of folks don't have a hose they can use if they are off grid and using bottled water, so a hose is not always an option. Whatever you use, make sure you dry off everything when done.
That should be obvious.

myocardia

Solray said:

I wouldn't leave anything on the panels after cleaning even if it's just water. A lot of folks don't have a hose they can use if they are off grid and using bottled water, so a hose is not always an option. Whatever you use, make sure you dry off everything when done.
That should be obvious.

Google "solar thermal panel", and you'll understand. They have zero glass, and produce zero voltage. They produce nothing other than heat (by being black, and absorbing sunlight), which in turn, heats the water.

Solray

Mine have glass panels that cover them and cause the heat to intensify.
The OP did not specify what type they have.

littleharbor2

I use a large squeegee/scrubber with a long screw in broom handle and a medium sized ice chest that the squeegee fit into. Works great although my array is on a flat roof so access is easy.

myocardia

Solray said:

Mine have glass panels that cover them and cause the heat to intensify.

Your solar thermal panels have glass over them, or your electrical solar panels (PV, in other words) have glass over them? If you mean thermal panels, what brand are they?

@littleharbor2 that's cheating! You could do back-flips on that low, flat roof.

cow_rancher

myocardia said:

Solray said:

Mine have glass panels that cover them and cause the heat to intensify.

Your solar thermal panels have glass over them, or your electrical solar panels (PV, in other words) have glass over them? If you mean thermal panels, what brand are they? 

"Good" Solar hot water panels have glass-aluminum construction, I have 4 from a previous house, which were Sunpower out of Phx, not sure it's the same Sunpower as today, this was from back in the 70's, I also have 4 new which were an insurance replacement from a fire that took out the other 4 sunpower panels that I was going to use.  The new ones are "Gobi", when installed, which hopefully will happen this fall, it should heat my hydronic floors about 80-90% of the time.  My location is SouthEastern AZ, at 5,000 feet.

Solar panels without glass are most likely for heating pools.

Rancher

littleharbor2

myocardia said:

@littleharbor2 that's cheating! You could do back-flips on that low, flat roof.


But too low to do a triple lindy into the pool.

aminaelis

Thank you everyone for your replies.   I cleaned them as instructed, wiped them as dry as possible too. Although, when it rains here, it often makes them more dusty again because rain picks dust and sandy particles - it's desert like landscape around. So they will need this clean up pretty often I guess...

aminaelis

And I also noticed that neighbors do not really bother much with cleaning their solar installation... 

littleharbor2

Incidental dust/dirt on the surface of your panels doesn't affect their output by much. There have been a few discussions here over the years documenting the losses from dirty panels. I removed a "non functional" system once where the panels were mounted on a flat roof. They were so covered in dirt that you couldn't tell if there were solar panels under there or plywood rectangles, or ??. Everything worked fine once cleaned. If you have birds liking to congregate on your array, that's a different story. their droppings will shade some cells, which might as well be all of them in series strings,

Lumisol

I use a diluted washer solution for auto windshields, it's made specifically for cleaning glass that is held in place with rubber gaskets and is safe for glass, rubber and paint.