>The change in wave length of the reflected light makes
>glass opaque to the reflected Infrared light and keeps it in the box.

        This is a revival of the late-1960s version of the Greenhouse
Effect.  It is a furphy.  A greenhouse  -  or a solar wax melter  -  works
by frustrating convection, not re-radiation.  It holds in the hot air.
        For present purposes, half the solar radiation is visible and half
IR.  (The UV, important in many ways, is a negligible fraction of the
energy flux.)  Darkish contents in the box absorb visible and IR.  These
contents then glow with IR, which does to some extent radiate back out thru
the glazing  -  just as well as the same IR wavelengths came in.  But the
warmed air can't get out and that's your greenhouse.

        Glass remains in general the champ.  Strong, doesn't go cloudy,
cheap or free as demolition windows.

R


-
Robt Mann
consultant ecologist
   P O Box 28878  Remuera, Auckland 1005, New Zealand
                (9) 524 2949