it is about 5 C warmer (or more) near the ground than perhaps 8 feet up. So modify a convential air conditioner to have a long 8 foot tube pointing up, then a mild little phovoltaic fan breezing the air in the tube.
The warm (outside) side of the air condition experiences air that might be 5 degrees C or more cooler, heightening efficiency imaginably more double digits more efficent than a tubeless air conditioner.-- beanangel, Oct 10 2016 @beanangel, I was thinking about posting something like this, but I was thinking of reaching much higher --- to air cool enough for cooling homes directly, rather than improving heat-pump efficiency. The air would be reached with an inflatable, hollow, coaxial conduit stabilized by guy wires. The air would be drawn down by an electric fan. The space between the layers provided by the coaxial aspect would thermally insulate the air stream as it passes through. By making the conduit inflatable, it could survive high winds by deflating it. I never looked up the typical temperature gradients though, so I don't know the temperatures to expect.-- Alvin, Oct 11 2016 Sounds like what's needed is a U-shaped inflatable tube with one leg black and the other leg silvered.
If the temperature at ground level is 30 C and the temperature at 100m is 25C, the difference in temperatures should cause air circulation; warmer air will rise in the black tube, and cooler air will fall in the silvered one.-- 8th of 7, Oct 11 2016 //survive high winds//
The problem here is you have to pull against those high winds to get air into the tube. Alternatively , just leave the tube and you'll at least have a wind-powered, fairly powerful fan sucking air into the abode. Connect it to a hose for an electricity-free central vacuum.-- Voice, Oct 11 2016 @Voice, I was thinking the conduit would be made of flexible plastic sheet, with fabric embedded in or surrounding the outer layer, while the inner layer could have plastic rings to maintain an open path on the inside. This all means that the "tube" would be collapsable to a compact lump of plastic, setting on the roof. If there were winds available, a scoop could be attached to the top end and one could then forego the fan.-- Alvin, Oct 11 2016 practical [-]-- Voice, Oct 11 2016 On a sunny 90 degree day it actually is 5C cooler just 2 meters up-- beanangel, Oct 12 2016 On a sunny 90 degree day it actually is 5C cooler just 2 meters up-- beanangel, Oct 12 2016 On a sunny 90 degree day it actually is 5C cooler just 2 meters up-- beanangel, Oct 12 2016 random, halfbakery