I’m embarrassed to say how long I had lived in this apartment before it dawned on me that I could use the kitchen and bathroom exhaust fans in the evening after the sun goes down, to similar effect. It really does make a difference!
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I live in Alabama and love my whole house fan! It’s original to the house (1963), loud as hell, and completely useless during our seemingly endless summers, but it is amazing during what passes for autumn and again in the spring, when the humidity is comfortable and the temps cool in the evening. Most people seem to toss them when they renovate older houses.
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Nope.
To melt 1 g of ice one needs 333 J, to evaporate 1 g of water (at room temperature) one needs about 2400 J.
So blowing air to melt ice instead of evaporating water is about 86% less efficient to remove heat.
There’s the advantage that the air would be mostly dry (so the room won’t turn into a moldy Petri dish), and (briefly) at a lower temperature.
Yeah, but once the 1g of ice is gone, you’ve got 1g of water to warm up and evaporate.
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Right, of course.
Mechanically, the ice should melt over a concertina filter, to increase the surface exposed air, otherwise it’d still be very inefficient…
But really, for me dampness is so much worse than high temperature than I never even considered getting one of those contraptions.
I’m not a germophobe, but the idea of a wet tissue thingy enclosed in a box and breeding molds and bacteria to then send them flying into the air has very little appeal to me.
EtA: In Rome we have ceiling fan in all rooms, they are reasonably effective, easing the evaporation of our own sweat. I also feel the quiet droning of the motor makes me sleep better 
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In Stockholm, I just leave the windows open during the night when (rarely) needed, living in a very quiet street.
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That reminds me the summer we were working in Italy our trick was to stick t-shirts in the freezer, just to get 5 minutes or so of cooling off when put on. Very temporary but felt soooooo good in the heat.
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I tried the ice tray thing and it worked for a few minutes and then I had a giant metal tray full to the brim with water to deal with.
I think I’m going to get the smallest windmill unit, as they’re on sale at Lowes. It says not to do through-the-wall mounting but I framed the wall to my office to hold a window unit so should be fine.
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There’s a limit on oversizing, though. If the AC unit is much too big for the load the risk is that it short-cycles; the unit bangs on, runs briefly, the thermostat is satisfied and the unit shuts off. While the room becomes cool, the run time is too short and doesn’t knock out the humidity.
Then the room stays m….
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Well I sure know one place that might have benefited from a few of these last week:
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it seems like having the motor inside the space being cooled would be a big efficiency hit 
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All of that, plus:
Here in Australia (and probably elsewhere), ceiling fans can be set for summer and winter. The “summer” setting is the one you expect - blows ceiling air down at you. “Winter” does the opposite: it pulls air up from the room and pushes it at the ceiling. The assumption is that you have a heater running, and the warm air has settled along the ceiling. A winter fan pulls the cooler air from around the floor and pushes the warm air down as a result. You don’t actually feel the air blowing past you, which is the right answer in winter.
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Portable A/Cs are less efficient than window units but maybe not by as much as you’d expect. The “hot side” inside the unit is insulated and vents out the tubing that runs to a nearby window.
Yup. They’re pretty good - if the volume they were designed for1) matches the volume of the room they are used for. Otherwise the poor thing struggles to little avail.
1) IME what it says on the box can be somewhat misleading there at times.
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That’s what I always think! I live in Canada. Why do nightclubs or server rooms need air conditioning in winter when there’s all that (famously!) cold air right there?
Before the ceiling fan era in my place, I always want to try to put in one of those window fan thingies at night and try and draw some of that cool, delicious air into my apartment. Doesn’t seem to work as well if you don’t have windows opposite each other to develop a crossdraft.
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Yeah for sure. BTU ratings are meaningless unless they tell you the standard it’s using.
I have two portable units that are 10000 BTU. One measured with the old ASHRAE standard is closer to 6500 BTU in the newer DOE standard. The other one is 10000 DOE which is closer to 14000 ASHRAE.
That’s because ASHRAE is a more rigid measurement cooling capacity while DOE is a more practical cooling capacity. Sort of like the difference in measuring a car’s horsepower at the engine versus at the wheels after that initial power output has gone through the to the place where it really matters.
Just be prepared for a shower of dust clumps as the former leading edges of the fan blades become the trailing edges twice a year.
Clean them first, you say? Bah!
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Does the direction actually matter? It seems like it would reach steady state circulation pretty quickly.
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I think it only matters if the body of the fan is made of cast iron, or if you like to keep the blades really sharp? 
(Serious meaning, though: there’s always a lot of debate about that, it seems…)
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