solar panel expansion

[Diver]

I' reading up on solar panels and contemplating few design ideas. I will most likely build a covered pergola, that will be 12x40 in dimensions to support the panels. It will be slightly slanted at about 30 degrees.

Originally I thought about placing 2'x20' or 4'x20' panels horizontally, but it seems that vertical orientation is preferred and sagging might be an issue even at small angles of incline. Another possibility is to place 12' or 8' long panels vertically to avoid that issue all together.

I read that the panel expand and contract with the temperature. Do they do that along 2 axis, the same directions as tubes go or perpendicular? I would have to put a good number of vertical panels in an array and I'm wondering how to accommodate if expansion takes place perpendicular to tube direction.

Thanks!

 

[Casey]

I can not answer as I do not know but maybe someone else does.

 

[Diver]

thanks Casey,

after some thinking, looks like i'm going with 4x10 panels oriented vertically so it's no longer an issue

 

[Isaac-1]

They do expand and contract in both directions, this is something you need to account for in your mounting design including the feed plumbing. If I were going to do what I picture you are proposing, I would use one of the stiffer 4x10 or 4x12 panels, like the Technosolis I used for my solar install (they are about as rigid as a thin sheet of plywood), instead of one of the individual tube style collectors which flop more like a wet noodle.

 

[pooldv]

I have a similar solar setup. There are pics of my solar install in my build thread in my sig that might be helpful.