Efficient Air-Conditioning Beams Heat into Space
Huh - I&#x27;m always interested in ways to make A&#x2F;C more energy efficient. Squeezing and un-squeezing gas seems so COMPLICATED compared to how easy it is to heat things up. Entropy is a cruel mistress. Anyways, it sounds like this is the important bit:<p>-<p>So Raman and electrical engineering professor Shanhui Fan made panels containing layers of silicon dioxide and hafnium oxide on top of a thin layer of silver. These radiate in a unique way: They send heat directly into space, bypassing the Earth’s atmosphere. The panels do this by emitting heat at infrared wavelengths between 8 and 13 micrometers. To these waves, the Earth’s atmosphere is transparent. What’s more, the panels reflect nearly all the sunlight falling on them.<p>For the new fluid-cooling system, the researchers made radiative panels that were each one-third of a square meter in area; they attached the panels to an aluminum heat exchanger plate with copper pipes embedded in it. The setup was enclosed in an acrylic box covered with a plastic sheet.<p>The team tested it on a rootop on the Stanford campus. Over three days of testing, they found that water temperatures went down by between 3- and 5 °C. The only electricity it requires is what’s needed to pump water through the copper pipes. Water that flowed more slowly was cooled more.<p>-<p>So it sounds like how space stations kick out heat; The ISS uses that sort of thing[1]. You flow coolant through things that heat up, like solar panels or a warm environment, and then you pump it into these bricks that don&#x27;t absorb heat from light. The coolant warms up the bricks, which emit that heat as infrared radiation. Planetside, I guess that you can&#x27;t let the infrared radiation be absorbed by the atmosphere, or it won&#x27;t cool anything.<p>So, maybe this could take the compression out of our current cooling systems - compress&#x2F;heat up, expose to outside temp, let cool, decompress&#x2F;cool, expose to inside temp, repeat.<p>My main question would be, is it capable of cooling beyond the ambient outside temperature? If so, how? I might be misunderstanding or missing something about how the &#x27;blasting energy away as IR radiation&#x27; thing works.<p>[1]: <a href="http:&#x2F;&#x2F;www.lockheedmartin.com&#x2F;us&#x2F;products&#x2F;HeatRejectionRadiators.html" rel="nofollow">http:&#x2F;&#x2F;www.lockheedmartin.com&#x2F;us&#x2F;products&#x2F;HeatRejectionRadia...</a>