Smart windows equipped with controllable glazing can augment lighting, cooling and heating systems by varying their tint, saving up to 40 percent in an average building's energy costs.
These smart windows require power for operation, so they are relatively complicated to install in existing buildings. But by applying a new solar cell technology, researchers at Princeton University have developed a different type of smart window: a self-powered version that promises to be inexpensive and easy to apply to existing windows. This system features solar cells that selectively absorb near-ultraviolet (near-UV) light, so the new windows are completely self-powered.
"Sunlight is a mixture of electromagnetic radiation made up of near-UV rays, visible light, and infrared energy, or heat," said Yueh-Lin (Lynn) Loo, director of the Andlinger Center for Energy and the Environment, and the Theodora D. '78 and William H. Walton III '74 Professor in Engineering. "We wanted the smart window to dynamically control the amount of natural light and heat that can come inside, saving on energy cost and making the space more comfortable."
The smart window controls the transmission of visible light and infrared heat into the building, while the new type of solar cell uses near-UV light to power the system.
"This new technology is actually smart management of the entire spectrum of sunlight," said Loo, who is a professor of chemical and biological engineering. Loo is one of the authors of a paper, published June 30, that describes this technology, which was developed in her lab.
Source: Princeton University
Journal Reference: Nicholas C. Davy, Melda Sezen-Edmonds, Jia Gao, Xin Lin, Amy Liu, Nan Yao, Antoine Kahn, Yueh-Lin Loo. Pairing of near-ultraviolet solar cells with electrochromic windows for smart management of the solar spectrum. Nature Energy, 2017; 2: 17104 DOI: 10.1038/nenergy.2017.104
(Score: 3, Touché) by Jeremiah Cornelius on Sunday July 02 2017, @09:58PM (3 children)
Users 0
You're betting on the pantomime horse...
(Score: 2) by mhajicek on Sunday July 02 2017, @10:08PM
In Soviet Russia Windows uses you. Everywhere else too.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 2) by inertnet on Sunday July 02 2017, @10:18PM
W.I.N.D.O.W.S.: We Install No Damned Other Working System.
(Score: 0) by Anonymous Coward on Monday July 03 2017, @04:34AM
Look, the submitter took great care to differentiate smart windows from microsoft windows!
(Score: 0, Offtopic) by Ethanol-fueled on Sunday July 02 2017, @11:18PM (1 child)
Everytime a woman is featured in an SN article, the first question which comes to mind is, "Is she hot?" Maybe there should be a dedicated "...but is she hot?" troll-user of SN.
Well, let's make that determination. [princeton.edu] She is fuckable but those eyes are scary. Unfathomable horrors lurk behind them and she's the kind of person who would murder you brutally (by stabbing, as she prefers her murders to be much more hands-on compared to the tedium of procuring and synthesizing dangerous chemicals) after fucking your brains out. She should probably also hire an eyebrow consultant, as the slope of her eyebrows causes her to look angry (a problem also shared by Michelle Obama until she got the memo) and only weirdos have any kind of hair on their face trimmed to pencil-thinness.
I predict that she will be charged for double-murder after discovering her lover in bed with his mistress and later found a bloody mess with lotuses and cherry-blossoms spread all over the grizzly scene of the murder.
(Score: 2) by realDonaldTrump on Monday July 03 2017, @08:34PM
If I understand the story -- and I think I understand the story -- she made a window that lets her control the flow of heat and light. She pushes a button, the heat comes through. She pushes another button, the heat is blocked. She pushes a button, you can see her whatever. She pushes another button, blocked. She likes being in control. She likes the cyber. And she's a tease. Not what floats my boat. And let me tell you, I bought Adnan Khashoggi's yacht. A 300-footer. With everything. With 210 telephones, 3 elevators, a hospital, and a helipad. With suede walls. And the price was a steal! 🇺🇸
(Score: 0) by Anonymous Coward on Monday July 03 2017, @01:00AM (5 children)
I took a great solar energy course in the MIT architecture department in the mid-1970s. This was one of the professors predictions for solar glazing. At the time, the concept he was working on with a material scientist collaborator was called "heat mirror", the idea was that it would change transmissiblity and/or reflectivity for different wavelengths of sunlight and heat. It was too early for them to get past some simple concept experiments, but I believe they were working with multi-layer membranes, possibly including liquid crystals. A few years later the Saudi's turned the tap back on, the world was awash in cheap oil, and solar was mostly forgotten for another generation or so.
(Score: 3, Insightful) by driverless on Monday July 03 2017, @04:25AM (3 children)
Say hello to the 13th century (or even earlier in some Arab cultures, depending on how far back you want to take it and whether something like a mashrabiya counts). This is basically a resource-intensive whiz-bang louvre or similar device. You don't need a "smart" anything, just some wooden slats and a cord. 100% renewable and carbon-neutral and every other green buzzword you want to throw at it.
About 95% of the time, "smart" != good, it just means "unnecessary technology" or "expensive toy".
(Score: 4, Insightful) by kazzie on Monday July 03 2017, @08:08AM (2 children)
Yeah, the principle of drawing the blinds to keep a house cool isn't new, but I've never owned a set of wooden blinds that close themselves when it gets too warm.
I have a sun-catching conservatory on the back of my house: great for helping to heat the house from autumn through spring, but it can bake things in the summer if its gets too much sun. I don't always guess the weather forecast corectly (or sometimes forget) and come home to an uncomfortably hot house. (No air-con, this is the UK we're talking about.) I can see value in this.
I also note that the "smart" here doesn't need to be linked up to the IoT in order to work. That also meets with my approval.
(Score: 2) by driverless on Monday July 03 2017, @08:13AM (1 child)
They're quite common in Europe, jalousies with automated control. They date back to at least the 1970s.
(Score: 2) by mcgrew on Monday July 03 2017, @06:25PM
Close to what I was going to say: finally, a smart device that can't be hacked! ...except maybe with a brick.
The #1 domestic terrorist organization in the US is ICE
(Score: 2) by mcgrew on Monday July 03 2017, @06:22PM
That grocer's apostrophe REALLY makes you look ignorant. Stay away from Facebook and Twitter for a while!
The #1 domestic terrorist organization in the US is ICE
(Score: 2) by lx on Monday July 03 2017, @08:18AM (2 children)
Infrared energy is light, not heat. It may produce heat, but so do visible light and UV.
I would expect better from an engineering professor at Princeton.
If popular science means dumbing down the science to the point of telling untruths then it's no wonder that scientific fact is seen as just another opinion.
(Score: 1, Funny) by Anonymous Coward on Monday July 03 2017, @10:28AM (1 child)
When you go into pedantic mode, do it right. First of all, there is no such thing as "infrared energy". There exists infrared radiation (which is electromagnetic radiation at a specific energy range), and that infrared radiation (like any electromagnetic radiation) carries energy. But it is not the energy that is infrared, it is the radiation.
Electromagnetic radiation is heat radiation if and only if it has a Planck spectrum. For temperature ranges typical on earth, that Planck spectrum has its maximum in the infrared part of the electromagnetic spectrum. An incandescent light bulb emits heat radiation with its maximum in the visible light range. And so does the sun.
No, it doesn't "produce heat". It may heat up other things (like any hot stuff does), and for heat radiation this heating up means heat exchange(!) between the photon gas and whatever is heated up by it.
(Score: 0) by Anonymous Coward on Monday July 03 2017, @04:36PM
If you are going to go full retardo-pedant you should get your facts right. An incandescent lightbulb emits about 90% of its radiation in the non-visible infra-red. This is why the greenies were so hot to replace them with CFLs.