I have a few rubber solar panels on my roof and after a few years they are starting to become gray and don't seem to be heating up the water like they used to. I was thinking that it might be a good idea to put something like this on it to get it nice and black again, but I notice that it says that it acts as a UV filter as well, which I am assuming will be a bad thing for getting the panels hot to warm up the water. What is recommended when the solar panels start to turn gray?
Getting your solar panel black
- Thread starter mikerobinson
- Start date
Welcome to TFP! 
Filtering UV is not a problem and could help make the panels last longer. There is minimal heating from the UV (< 400 nm) and represents about 3% of the total energy while visible light (400-700 nm) is about 48% and infrared light (> 700 nm) is about 49%.
I'm not so sure, however, that the product you describe will restore the blackness of the panel. They aren't usually made like tires that are a mix of natural and synthetic rubber and fibers, but rather from a soft synthetic rubber such as EPDM or soft plastics such as polyethylene or polypropylene. You could certainly try it on a small section to see if it works.
The panels you have must not be of very good quality since the color should be mixed throughout the plastic (as with FAFCO panels) and not just a surface coating and not something that fades over time. My 9-year old panels look as black as when first installed and they heat the pool efficiently.
Filtering UV is not a problem and could help make the panels last longer. There is minimal heating from the UV (< 400 nm) and represents about 3% of the total energy while visible light (400-700 nm) is about 48% and infrared light (> 700 nm) is about 49%.
I'm not so sure, however, that the product you describe will restore the blackness of the panel. They aren't usually made like tires that are a mix of natural and synthetic rubber and fibers, but rather from a soft synthetic rubber such as EPDM or soft plastics such as polyethylene or polypropylene. You could certainly try it on a small section to see if it works.
The panels you have must not be of very good quality since the color should be mixed throughout the plastic (as with FAFCO panels) and not just a surface coating and not something that fades over time. My 9-year old panels look as black as when first installed and they heat the pool efficiently.
Thanks for your quick answer. For some reason the board didn't notify me of your reply, so I didn't notice it until now. I'll give it a try on a small part to see what happens.
