Using the Sun to Keep Cool

Solar source absorption cooling is not new, I can remember installing one some 30+ years ago...

http://www.sciencedirect.com/science/article/pii/S0038092X01000986

Yeah, LiBr absorption is a mature technology. Getting to -60 C though is impressive, and not something of which LiBr absorption is typically capable. Problems are likely for ammonia absorption too. In either case, the problem would be water freezing, whether water acts as the refigerant or the absorbent.

I find the claim of -60°C dubious with a Water/ammonia system...

http://en.helioclim.fr/technologies/

Might be an ammonia hydrogen system, or ammonia butane (a la Einstein et al) system.

If any aqueous ammonia is around 35% ammonia in the cold areas, -60 C should be workable.....but things could go catastrophically wrong if concentrations go awry and pipes freeze.

Well they certainly could have a proprietary formula for this system, but they make no mention of it on their website, just the water/ammonia 2 stage as their means of this claim...There certainly are heat exchange fluids that work at these low temps, such as Dynalene MV, but I don't know of any suitable companion refrigerant that would be suitable for use in an absorption system....