Why use glass at all? Isn't PVA enough?

[arond]

Hello, I have a question about DIY solar that I couldn't find the answer to anywhere else, it seems that good solar performance could be obtained using just PVA (Edit: EVA) or UV stabilized epoxy encapsulation alone so why use glass at all? It seems to me that all glass does is add weight, cost and heat retention. Opinions? Thanks, Aron

[inetdog]

Hello, I have a question about DIY solar that I couldn't find the answer to anywhere else, it seems that good solar performance could be obtained using just PVA or UV stabilized epoxy encapsulation alone so why use glass at all? It seems to me that all glass does is add weight, cost and heat retention. Opinions? Thanks, Aron

It adds rigidity, which is necessary since the cells are brittle and fragile.
That same rigidity can help reduce flexing from wind loads when only the edges are supported.
It adds protection from mechanical damage (hail, birds, nuts, etc.)
A thick enough layer of epoxy to provide protection will cost a lot more than glass and will absorb or reflect more light.

[arond]

It adds rigidity, which is necessary since the cells are brittle and fragile.
That same rigidity can help reduce flexing from wind loads when only the edges are supported.
It adds protection from mechanical damage (hail, birds, nuts, etc.)
A thick enough layer of epoxy to provide protection will cost a lot more than glass and will absorb or reflect more light.

True, I was thinking for rigidity the mechanical backing could be solid aluminum or fiberglass composite, I've seen solar shingles that appear to only use eva film rated for 20+ year life so I assume mechanical damage must be minimal for them. With the right mix of plastics it seems it would be feasible to go glass free somehow. thanks for your input

edit: here's a site that makes glass free panels, I'm not sure how they do it or what the cost is: sunshineworks.com/thin-solar-panels. (edit: somebody broke the link, for those wondering the product was "Neutron 123 Watt Glass Free Thin Solar Panels")

[inetdog]

I've seen solar shingles that appear to only use eva film rated for 20+ year life so I assume mechanical damage must be minimal for them. With the right mix of plastics it seems it would be feasible to go glass free somehow. thanks for your input

So far the experience with solar shingles has been pretty unsatisfactory. Either they are too hard to install, not durable enough or do not maintain their output well enough. The first marketers of these gave up after awhile. There is now an attempt to get the product going again, but it is not clear yet what, if anything, is different.

[Naptown]

Those appear to be an accident waiting to happen.
No approvals, listing or warranty noted.