Looking at a second hand rig and it has 3 solar panels side by side across the width of the motorhome roof with no gap underneath for air flow . Is this alright , they have been on the rig for sometime now so the owner says. They seem to be working ok will I have to lift them up. Don't know what wattage they are but they are about a 1200mm long x 600 wide approx. Owner couldn't tell me the size of them .
It is best to mount solar panels so some air can pass under them and heat can disperse, having said that you don't need a gap under them you could drive a semi loaded with a D8 under them..lol
If it has an alloy frame around it there is air space between the bottom of the frame and the bottom of the panel and if the top of the motorhome is slightly curved then it would be able to disperse its heat..
I wouldn't worry too much about it if they are already there, they may be older Amorphous panels which can handle the heat better, and just about all of the latest thin film PVs are intended to be fitted directly to a substrate without any air gap.
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