Anyone a self proclaimed hydronics/solar expert?

[Speeddog]

Cooling towers are used in large buildings, is that along the lines of what you're thinking?

[Drunken Monkey]

I was looking at a few different models of evaporative heat exchangers.

Then I did some research on the wet-bulb vs. dry bulb temps here in San Francisco... This area isn't a great candidate for a system like this, I'm afraid.

A system like this would be great anywhere where it's hot and relatively dry (The SE and the NE) but anywhere else, it's not ideal. And in some areas (notably the deep south) it'd be useless.

Ah well. Mind you, it might work well with a ground-based heat exchanger but it'd need a good control system to keep the water temp at or above the dew point.