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Professors Claim Passive Cooling Breakthrough Via Plastic Film (sciencemag.org)
What if you could cool buildings without using electricity? charlesj68 brings word of "the development of a plastic film by two professors at the University of Colorado in Boulder that provides a passive cooling effect."
The film contains embedded glass beads that absorb and emit infrared in a wavelength that is not blocked by the atmosphere. Combining this with half-silvering to keep the sun from being the source of infrared absorption on the part of the beads, and you have a way of pumping heat at a claimed rate of 93 watts per square meter.
The film is cheap to produce -- about 50 cents per square meter -- and could create indoor temperatures of 68 degrees when it's 98.6 outside. "All the work is done by the huge temperature difference, about 290C, between the surface of the Earth and that of outer space," reports The Economist.
The film is cheap to produce -- about 50 cents per square meter -- and could create indoor temperatures of 68 degrees when it's 98.6 outside. "All the work is done by the huge temperature difference, about 290C, between the surface of the Earth and that of outer space," reports The Economist.
You're the type person that should be shot in the head. Mao was a motherfucking mass murder in the same style as Stalin and Hitler. Fuck him in the eye socket and you too.
You non-RTFA infidel! The article states the temperatures as 20C and 37C respectively.
Ask me how the Heisenberg Principle may or may not have saved my life.
"Passive cooling on the order of what this article talks about would seem to be too good to be true. If it is true these guys should be filthy rich soon."
Don't forget to sell your Air Conditioning stock.
Its interesting that they have made the film, yet have not demonstrated it in a practical application. That makes me skeptical as they are relying on performance claims when they shouldn't have to. Why could they not take the film and cover a small structure (like a shed), and simply tell us the resulting cooling effect? And maybe compare against a simple reflective coating
It's called physics, even if you don't find it interesting.
1) Letting visible light through in principle lets the PV work while keeping it cool. The increase in output with lower temperatures is quite significant, thus the presence on the market of combined PV/Thermal panels for example. (And absorbing more of the visible light and removing the energy as electricity rather than letting it turn into heat would be good too, natch, and that one is being worked on.)
2) Outer space is at ~3K/-270C: having that as your cold sink *day and night* is really quite significant. What I cannot work out is if clouds are transparent at the same wavelengths, eg if this could be used to make the cold end of a Seebeck device even under cloudy skies: that would allow a small amount of power generation day and night also, if so.
This looks plausible to me and and an astonishingly good thing if it works even a 1/10th as well as the researchers hope.
Sometimes the science is good before the marketing people get to it.
Rgds
Damon
http://m.earth.org.uk/
All these 'advances' are a scam. Remember how computers were going to get more powerful, how we'd have literally megabytes of storage available? And they'd get smaller so we wouldn't have to lug around a briefcase+ size device like one day they'd be phone size? What happened to any of that? Don't get me started on the stories of how one day we'd be able to engineer genes directly. It's all pie in the sky. And like you say, medical research, all those stories about keyhole surgery and designer drugs. Never gonna happen.
I think maybe you're on the wrong website, you don't seem to be interested in new discoveries. You might be happier with a site which concentrates on something like "new products coming out this year."
Many of us enjoy reading about new discoveries, knowing that not every promising new discovery will lead instantly to a mass marketed product. (If it ever does.) Every time there's a story about research on improving solar panels or battery efficiency there's always people complaining that they never see these things coming to market, ignoring the steady improvements that we see in both over time. For every story about improving ranges of electric vehicles there's someone who says it's useless because it doesn't meet their use case.
If you really are an old guy think about all the progress you've seen in your lifetime. It didn't happen all at once, but we've sure come a long way. My first computer had 48 kb of ram, 5 1/4" floppies as the only storage, and I used a Model 33 Teletype as a printer. It was a home built Southwest 6800, for those old enough to know what that was.
Just WTF are people being taught these days?
Apparently they're not taught the difference between a real comment and trolling
lucm, indeed.
No you couldn't embed them in glass, because the glass beads work by being resonate at a frequency that atmosphere is transparent to. The beads aren’t normal glass, they are transparent infra-red, most glass is rather opaque in infra-red. what you could do is apply it like a window tint, but I suspect it would have a lot of distortion and possibly an opalescent effect.
The film unsilvered is highly transparent to visible light, so the ideal application, would be to apply it to PV solar cells to help cool them and prolong their live span.
Apocalypse Cancelled, Sorry, No Ticket Refunds