Painting solar panels....

[karenh]

Okay, my solar panels are about 7 years old and still going strong with no leaks. But..... this year they are just not raising the temp as much as usual. Flow is good, run them seperately off an intex 2500gpm pump. I think the problem is that they are no longer the dark black that they once were. I want to paint them but don't know what type of paint to buy. Bought the Fusion, but the wind won't quit blowing long enough to spray them. Is there something that can be rollled on that will work?

Thanks!!
Karen

 

[Isaac-1]

If you are going to try to paint them, I would certainly do a test patch, for one thing not all black paints are "black" in the infrared part part of the spectrum, so might not absorb heat as well as they are now unpainted. I would also worry about any paint increasing plastisizer migration and therefore shortening the life of the panels.

 

[karenh]

Thanks Isaac. Need to do some more thinking. How long do the solar panels usually last?

 

[Suziqzer]

I don't know from experience, but I'd venture to guess from what I've read here that you're doing quite well at 7 yrs ..

 

[Samantha Sabrina]

What are the collectors made of?

We built our own using PVC, and painted it with flat black spray cans, and it worked great until the PVC basically melted from the heat, (didn't use the sch 40, and didn't run the pump during the heat of the day whlle they had water in them).

 

[karenh]

not sure which brand, but just a 4 x 20 setup. Hubby could build it, but unfortunately right now he's working 11 hrs a day 6 days a week (on midnights) so I don't think building it ourself right now is worth it. Tomorrow I'm going to change out the intex filter for a new one. It's not dirty, but we've used the same one for a couple of years. Give it a couple of days and if no improvement, paint them with krylon. As old as they are, if they fail, I've gotten my money's worth. Here's a pic of the setup.

 

[Samantha Sabrina]

Karen,

Sounds like a plan!

 

[yeggim]

not sure which brand, but just a 4 x 20 setup. Hubby could build it, but unfortunately right now he's working 11 hrs a day 6 days a week (on midnights) so I don't think building it ourself right now is worth it. Tomorrow I'm going to change out the intex filter for a new one. It's not dirty, but we've used the same one for a couple of years. Give it a couple of days and if no improvement, paint them with krylon. As old as they are, if they fail, I've gotten my money's worth. Here's a pic of the setup.

You could get a significant improvement by hooking those two panels in parallel instead of in series like they are now. Also by having that open frame you are prone to more convective heat loss by having both sides open to air movement.

 

[karenh]

K... New plan of action... would black plastic underneath help? Or would I need something thicker? A quick run to lowes for some fittings and I can switch them to parallel. Thanks everybody for the input, will let you know how it goes.

 

[yeggim]

K... New plan of action... would black plastic underneath help? Or would I need something thicker? A quick run to lowes for some fittings and I can switch them to parallel. Thanks everybody for the input, will let you know how it goes.

Black plastic will help but plywood covered with roofing felt would be better. Your biggest boost will come from running the panels in parallel. I have two panels like yours. Last year they were hooked up in series. This year they're in parallel and I see a marked improvement.

 

[acroberson]

Your much better off doing PVC and putting aluminum behind the PVC over the wood. You will get heat gain from both sides basically. Don't use anything less than schedule 40 or your gonna burn it up. At least thats what my friend up north did.