> - 4. Al cooking foil (non adhesive backed). Cheap, available, lower refle=
ctivity

Are you sure about that "lower reflectivity=94 part?  Is cooking foil diffe=
rent in different parts of the world?  (in the US, you get one dull side an=
d one very shiny side.)  Ancient amateur =93solar power=94 books used glued=
 cooking foil almost exclusively.

thickness may matter.  Some of the aluminized mylars are designed to be par=
tially transparent.


> cooking, water heating and water sterilisation.

You might want to consider copper, which is quite reflective in IR.  Normal=
ly pretty expensive, but perhaps with surplus PCB material=85


> - 10. Front surface silver mirror using silver nitrate + clear coating.

Possible explosive residues; it would make me nervous in the quantities you=
=92re talking about.  Also, I think you need a really smooth surface (ie gl=
ass) to get a reflective layer.


https://www.photonics.com/a25501/Mirrors_Coating_Choice_Makes_a_Difference

BillW


--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.