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Scientists Develop Solar Cell That Can Also Emit Light
An anonymous reader writes: "Scientists at the Nanyang Technological University have developed a solar cell that not only converts sunlight into electricity but also emits light as electricity passes through it. Tuning the composition of the solar cell enables it to emit different wavelengths of light (abstract), and because it is only about 1 micrometer thick, the material is semi-translucent and therefore could potentially be used in windows. The solar cell is comprised of the semiconducting mineral perovskite, which has been studied as a replacement for silicon in solar panels since 2009. Perovskite solar cells are not yet as efficient at energy conversion as silicon solar cells, but gains in this area of development coupled with cheaper manufacturing costs (10-20 cents per watt projected as opposed to 75 cents per watt with silicon solar panels and 50 cents per watt with fossil fuels) make perovskite a popular subject matter in the solar cell industry."
Didn't Heinlein come up with a similar concept? In the story with the moving roads?
"Ralos Cell"
Table-ized A.I.
o Solar cell that also emits light
o Sandwich it with a perfect mirror
o Short the leads together
o Infinite energy!
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
Infinite energy.
Genius...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Douglas-Martin sunpower screens, which also appeared in "The Roads Must Roll"
A window with tunable coloring.
Could this be used to make displays? Pros/cons?
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The Solar Powered Flashlight is a reality
Speakers can be used as microphones.
LEDs can be used to detect light.
Motors can be used as generators.
Now some solar cells can emit light.
Problem is it's matter of efficiency, which is always more of a one way street.
Better known as 318230.
by Robert A. Heinlein postulated a solar cell that would emit light http://en.wikipedia.org/wiki/L.... The story came at it from the opposite direction -- a lighting panel that turned out to also work as a photovoltaic cell. Heinlein's story was published in 1940. Only took 3/4 of a century for engineering to catch up with science fiction.
When the article references perovskites, it is referring to a crystalline structure similar to the mineral perovskite (calcium titanate). These solar cells are NOT made of calcium titanate, nor is calcium or titanium even in them. Instead, they are make of organic - inorganic halides, in this case: CH3NH3PbX3 (where X = Cl, Br, I). The proper wikipedia link for the summary is: https://en.wikipedia.org/wiki/...
Any solar cell will emit light ... if you run enough current through it.
I remember the Heinlein story - it's been many years, I'll have to dust off that old book and read it again - but I also recall that regular LED's have always done this too, but just very poorly on the light to electricity conversion part. Seems I remember a project long ago taking advantage of this - something from Forrest Mims maybe?
Maybe the equipment needed to generate electricity from fossil fuels costs 50 cents per watt, but then you also need to buy the fossil fuels. I would expect the cost of fossil fuels would be measured in cents per Joule. If solar cells can produce electricity for 10 cents per watt with no fuel costs, I think we should work on scaling this up as fast as we can. We can all have more energy for less money than ever before! Of course, we also need to work on how to store energy produced on sunny days for use during the night and cloudy days.
What a fool believes, he sees, no wise man has the power to reason away.
Let me know when reality starts to look anything like your cost projections. I'll be over here, not holding my breath.
so you can have a job in one of China's call centers set up to do customer service while the US was too busy trying to have LGBTQ liberal arts programs for illegal Mexicans who are illiterate in their own language.
It's transparent solar panels on top of transparent solar panels.
It's transparent solar panels all the way down...
Can someone who understands the subject matter better than I do please explain to me how "cents per watt" is an applicable comparative metric for fossil fuels and solar cells?
It would (at least apparently) seem to me that when you use a unit of fossil fuel, it is gone. By contrast, if you have a solar cell, it will continue to be useful for as long as the sun and the cell have line of sight.
So aren't fossil fuels inherently measured in Joules?
So we could have a torch (sorry, flashlight) that only works in sunlight ... ? I'm not sure I'd buy one of those.
"Cats like plain crisps"
for instance, how many times did they make one a noise-emitting diode?
if this is supposed to be a new economy, how come they still want my old fashioned money?
Solar panels are fundamentally identical to LEDs, just optimized to absorb light instead of emit it. Forward-biasing a solar panel and measuring its light emissions is a common method of inspecting the panel for damage. Perhaps they managed to get this particular solar cell technology to emit visible light for the first time? Silicon solar cells generally only emit infrared light, but it's pretty easy to get a gallium arsenide cell to glow red without damaging it.
Another one of those "nanomaterial" stories. Claims of "cheaper manufacturing costs" for a product not yet produced in volume. Yet another "solar cell made with printing technology" scheme. Sigh.
So this thing is one micrometer thick and they want to print it on windows. How long does it last, hammered by UV and weather and thermal cycling? Lifetimes for silicon solar panels are now up to 25 years (warranties are available for that long), and there's falloff in output over that time. Can a 1 micrometer film match that? Realistically, it's going to have to be behind a protective layer. Maybe it could be on the surface of the middle layer in double-pane glass, but now you have a complex sandwich to manufacture. There goes the "cheap manufacturing".
Vertical windows are poorly oriented for capturing power. Solar shingles are better oriented. (Also, they exist, and you can buy them now.) And, as the head of Applied Material Solar pointed out a decade ago, half the cost is installing the thing. These guys need better numbers to back up their cost claims.
If you reverse the voltage enough on a Gallium Indium Arsenide solar cell it will glow red just like a diffuse light emitting diode. You have to remove the protection diode from the cell for that to work however.
That's nothing, while learning electronics as a kid, I invented a way to turn LEDs into Smoke Emitting Diodes...
I've got better things to do tonight than die.
> coupled with cheaper manufacturing costs (10-20 cents per watt projected as opposed to
> 75 cents per watt with silicon solar panels and 50 cents per watt with fossil fuels
Ummm, you can buy silicon solar panels on the market for about 55 cents.
Even retail is 70 to 80.
Does this mean these cells could be installed over farmland/ in greenhouses so we could get double use out of the same land? I kinda like this idea.
you don't eat crackers in the bed of your future--or else you'll get all scratchy
Any common silicon solar cell will emit infrared light if you pass current through it. This effect is used during manufacturing to characterize defects.
http://www.mpi-halle.mpg.de/mpi/publi/pdf/8470_08.pdf