FYI ...
I haven't stopped in to check on the costs but there is a new Alternative Energy Store on a real (grass!) lot in the middle of downtown Santiago on Calle Restauracon somewhere near, maybe at 30 de Marzo. Check it out, I plan too.
Solar panels do not cost that much. A full 7-10KW system might cost US$15K to US$20K but at the rates they charge for power here you'd have your money back in three years! That's a hell of a quick return compared to anywhere else in the world.
As for solar for water heat, ah, sorry but, DUH! P&A all you need is to bury maybe 1000 feet of plastic pressure water tubes under your concrete or stone driveway/sidewalk/poolpatio, connect it to an old hot water tank, not connected to electricity, and -presto- instant hot water! The sun's so strong here that's a snap.
Using a solar panel to heat the water down here is like swatting a mosquito on your forehead with a sledgehammer.
Tom (aka XR)