Umbra House

I find myself in possession of many rear projection screen TV's, (like 40 or so), and will have to take them all to the recyclers as we switch to flat screens in the rooms.

I got to thinking that the second screen inside each one of these things is a Fresnel lens and it seems a shame for anyone to not have at 'Least' 40 of those hanging around, but what to do with them?
I'm not sure that I have either the time or the give-a-crap to disassemble and remove all of them let alone put them to the use I have in mind, but I thought you guys might get a kick out of the concept.

Some plants don't like as much sunlight as others so I am thinking of constructing the roof of a shade-house portion of a greenhouse from these panels.
This would have the effect of casting an umbra over that section creating a shade house without ever having to replace the shade cloth, which would be nice, it just seems a shame to waste several hundreds of degrees focal points just to cast shade.
So I propose to hang aluminum balls from chains attached to the roof which hang at the focal points.
Even in winter this should radiate quite a lot of heat on sunny days but my main thought was to integrate the drip system to run a trickle of water down the chains which would flash steam once contact with the balls was made.

This should cause the humidity within the greenhouse to remain at semi-tropical levels and may allow for growing many plants which would otherwise not grow at all at this latitude.

Prior art ala [ninteenthly]
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