Community Forums

rayza · 07-08-2019, 03:15 PM

I am looking to put solar panels on the roof of my Class A.

I was wondering if the solar panels provide any sort of insulation against heat (think Arizona in the summer). I am looking to rail mount them so there would be a small air gap under the panel itself, I am thinking that the panel would provide a nice reduction in the amount of heat that even makes it to the roof.

Has anybody mounted their solar panels super close to the front edge of the roof?

Sbrownstein · 07-08-2019, 03:29 PM

Solar panels hate...hate...hate heat. A good air gap below is the best you can do but you should have one. Close to the front is probably fine as long as you leave some space behind the cap for some turbulence. Wouldn't want air plow under them to try to lift them too much.

rayza · 07-08-2019, 03:36 PM

Quote:

Originally Posted by Sbrownstein

Solar panels hate...hate...hate heat. A good air gap below is the best you can do but you should have one. Close to the front is probably fine as long as you leave some space behind the cap for some turbulence. Wouldn't want air plow under them to try to lift them too much.

I know it reduces their effectiveness, that can't be avoided :(

I am wondering if they will also help keep heat off the roof to provide some additional insulation to the coach. My thought (and I could be wrong) is that the solar panels will take the majority of the brunt of the heat/sun and stop it from hitting the roof. The gap underneath should help to dissipate the heat and thus I will get a benefit by having them keep the roof cooler and keep the motorhome cooler?

Sbrownstein · 07-08-2019, 03:37 PM

Should shade the roof...FWIW.

Gary RVRoamer · 07-09-2019, 10:26 AM

I suppose t helps, but I doubt if it makes a notable difference.

vsheetz · 07-09-2019, 11:01 AM

I installed 28 250w panels on my fixed residence 5 years ago. They cover about half of my south facing roof. An unexpected benefit was a noticable reduction in attic temperatures due to much of the roof being not directly exposed to the sun. This contributed to less air conditioning run time. I also noticed a thermostaticaly controlled attic exhaust fan would start latter in the morning.

I did a bit of research at the time. A known phenomenon. But difficult to quantify. I also spoke with my installer, who had similar reports from other customers.

So, yes, I think it is a factor. How much, cant say.

TLGPE · 07-09-2019, 11:12 AM

There is another thread running currently about putting a canvas shade over the roof to do exactly that. It definitely helps. Just holding newspaper up to block the sun on your face fakes a huge, immediate difference.

Cover your roof and you will feel the difference.

Tom

Dutch Star Don · 07-09-2019, 11:51 AM

I think "vsheetz" has it right. There may be some benefits, but very hard to quantify without testing. I would think that the advantage would be minimal. It would also depend on how much of the roof you cover with solar.

Bobkat3080 · 07-11-2019, 10:53 AM

We had 8 panels installed on our 35' motorhome right after purchase so we have no "before" to compare with "after", but the roof under a panel is somewhat cooler to the touch than a section exposed to the direct sun.