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Solar Cells That Emit Light Break Efficiency Record
benfrog writes "Researchers at the University of California-Berkeley say they have come up with a counter-intuitive way of making solar cells more efficient — making them emit light. In a press release the scientists claim to be the first to demonstrate that the better solar cells are at emitting photons (the more LED-like they are), the more efficient they are at generating electricity. However, 'unlike an LED, the electrons in a solar cell are absorbing photons from an exterior source as well as emitting their own.'"
Why don't they just funnel the emitted light back to the solar panels and thus make them independent of an external light source?
This would be great for space colonies and sea-floor dwellings.
Thermodynamics and all that. But you could probably sit a couple of these facing each other and recapture some of that light. Also, I'd expect space colonies to have relatively easy access to an external light source.
William of Ockham had no beard. The most likely explanation is that it was chewed off by squirrels every morning.
Make the solar cells part of modular homes where the roof and panel are built as one in a mass-production factory.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
Um, if someone needs the relevant college-level courses to understand this, then by definition it is NOT intuitive.
What do you think "intuitive" means exactly?
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
This is so cool. Every day brings us closer to glowy alien crystal energy technology.
as a slashdotter, the rest of us slashdotters presume that you're a more-than-competent physicist, chemist, biologist, astronomer, economist, engineer, gamer, proofreader, and Dr. Who/BSG/Star Trek/Star Wars/Matrix/LOTR archivist. if you're not, someone who is will pull your card.
plus, isn't sophomore college physics, like, a facebook app or something by now?
insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
That joke stopped being funny years ago - solar powered LED flashlights are on the market - I own one.
Sound useless ? It's not. It has a battery - during daytime it charges the battery from solar power, when you use it at night, the battery powers the LED lights.
It's a wonderfully useful tool on camping trips. As a bonus - since the battery isn't replaced during the lifetime of the device it has much less of a pollution (battery-acid) impact (granted this may be less of a consideration in some countries -mine has no systems in place for proper disposal/recycling of battery cells and people just toss them in the trash when they are used up).
That LEDs have become so powerful while remaining so efficient has led to us being able to do a lot of really cool things we weren't able to do even quite recently. :D
Frankly compared to things like LED based airport runway signal lights a solar powered flashlight isn't even all that impressive
Unicode killed the ASCII-art *
The vast majority of people also have crappy common sense. Saying something is intuitive without stating what background is required for it to be intuitive is just a dick move trying to make everyone else look stupid for not knowing everything you know. I learned a long time ago that things I think are obvious are frequently not to other people.
Of course, some of those things include not posing for photos on railroad tracks and making your kids ride with their seat belts buckled. The "bowling ball and a feather falling in a vacuum" question decidedly takes the back seat compared to the lack of intuition some people exhibit.
in.tu.i.tion/,int(y)oo'iSHun/
Noun:
(1) The ability to understand something immediately, without the need for conscious reasoning.
(2) A thing that one knows or considers likely from instinctive feeling rather than conscious reasoning.
Synonyms: insight - instinct
Note there is nothing in the definition about laypersons, or a priori comprehension. Intuition is defined by the absence of conscious reasoning, not by the absence of all reasoning. A large portion of our processing is unconscious, below the surface cognition we normally consider "thinking". The brain is massively parallel and is constantly processing a vast amount of data. Some of this we are aware of, the conscious portion. Other portions only come to the surface in the form of dreams. But most of it we never really see.
Your education and experience are part of this processing, and the more "education/experience/whatever" you have on a particular subject matter, the better your intuition is on that subject matter. This is not voodoo, it simply means the processing has been integrated into the deeper regions and we no longer have to actively or consciously think about it. To the conscious mind, it's like we "just know it".
As an example, a beginning driver, especially on a stick shift, will be thinking about details like gas pedal, brake pedal and clutch pedal timing, which gear to shift to, when to shift to neutral, and on top of all that, steering and navigating. An experienced driver doesn't need to consciously plot the gas off, clutch down, shift, etc... steps, they basically happen automatically. Some will argue it's muscle memory, but it's more than just the movements. The timing of all that, of what to do and when to do it, requires being able to integrate multiple data streams.
Another example, diagnosing computer problems. I've been fiddling around with computers for decades, and basically, family and friends come to me when their computers "don't work". Many times, they'll be describing (in non-tech terms) the problem and I'll "just know" what's wrong when they're barely done with the second sentence. I don't think "a priori" is correct, at all. If I I didn't have the education/experience/whatever, I simply would not be able to figure that stuff out. But because I do, I can, often intuitively, meaning, I don't have to consciously think about it. The character Dr. Gregory House, from the House, MD TV series, also displays this. His expertise is broad and deep, and so he can intuitively figure out obscure medical problems.
The brain is a constantly self-adjusting neural network, sort of like an FPGA, and although they aren't exact analogies, one can think of education as data/software. Early on, you're thinking about it and solving problems in software. But given time and practice, the software in the brain migrates into the hardware, kind of like programming an FPGA. Once it's coded in the FPGA, it can mostly avoid using the stack and registers (your conscious mind) and you "just know" the answers/solutions/whatever. And yes, intuition is very personal. What is intuitive to me will not necessarily be intuitive to you, and vice versa. We have differently-programmed FPGAs.
Excuse me, wtf r u doin?