Bouphonia is always an interesting visit and Fridays usually have something of a roundup of items which might otherwise have slipped under the radar. This is one worth looking into further.
On those hottest days, when the air conditioner is switched on, doesn't it make sense to have the air-conditioner driven by solar energy?
Now it looks like a Spanish company, Rotartica, has put it all together, by combining evacuated tube thermal collectors with a water-heated absorption chiller, and sized it at 4.5Kw (1.28 tons) for residential use, all packaged in a neat little box. From an operation point of view it is very simple: you put hot water in, you get cold water out, which you can run to a conventional fancoil. The hot water in can come from any source, but evacuated tube collectors, which used to be very expensive, are pretty affordable now.If you're into the technical side of things it's probably best to check out their website for more information. There's no discussion of the cost, but you can guess, for the time being anyway, it's probably pretty high.