Our house has 10 solar collector panels, each 1 by 2 meters, installed around 20 years ago. By now their polycarbonate covers are breaking down due to the elements, and we've thought about the possibility of adding a UV-blocking layer above them and maybe some photovoltaics inside while replacing the original covers.
In theory, the UV from sunlight would be blocked by the outmost layer, then the new polycarbonate sheets would let visible light and infrared through, below that the visible light would be captured by a layer of photovoltaic foil and finally the infrared radiation would heat the water in the collector pipes.
So far I haven't found any outstanding problems with this setup, since PV cells always used to have UV-blocking coatings to reduce degradation by UV (therefore pre-filtering UV should not reduce the efficiency of PV cells), and IR beyond 1120 nm is unusable for PV cells: pveducation.org.
Does this approach hold water or is it just a pipe dream due to some unavoidable factors?