@gerrymcgovern I'm quite surprised that swamp coolers are cheaper to operate than the more typical closed-loop cryo units. Without real numbers I have to assume it has to do with lack of externality cost, or some other strange economics. I know rejecting heat out of an exchanger in arid environments is less efficient than normal, but it's not that much...

MTW/HTW systems also get a little bit of advantage, because they're able to reject to ambient without quite as much effort.

All my experiences with closed-loop DC cooling systems, as my local area is not reliably dry enough to use a swamp cooler, therefore I can't really speak intelligently about systems that evaporate to the atmosphere.

My gut says that the cost of water should increase in these areas, eventually to a point where it's just too expensive to use lossy systems.