Transparent Solar Panels For Windows Hit Record 8% Efficiency (umich.edu) 60
Bodhammer shares a report from the University of Michigan: In a step closer to skyscrapers that serve as power sources, a team led by University of Michigan researchers has set a new efficiency record for color-neutral, transparent solar cells. The team achieved 8.1% efficiency and 43.3% transparency with an organic, or carbon-based, design rather than conventional silicon. While the cells have a slight green tint, they are much more like the gray of sunglasses and automobile windows.
The new material is a combination of organic molecules engineered to be transparent in the visible and absorbing in the near infrared, an invisible part of the spectrum that accounts for much of the energy in sunlight. In addition, the researchers developed optical coatings to boost both power generated from infrared light and transparency in the visible range -- two qualities that are usually in competition with one another. The color-neutral version of the device was made with an indium tin oxide electrode. A silver electrode improved the efficiency to 10.8%, with 45.8% transparency. However, that version's slightly greenish tint may not be acceptable in some window applications.
Both versions can be manufactured at large scale, using materials that are less toxic than other transparent solar cells. The transparent organic solar cells can also be customized for local latitudes, taking advantage of the fact that they are most efficient when the sun's rays are hitting them at a perpendicular angle. They can be placed in between the panes of double-glazed windows. [The team is] working on several improvements to the technology, with the next goal being to reach a light utilization efficiency of 7% and extending the cell lifetime to about 10 years. They are also investigating the economics of installing transparent solar cell windows into new and existing buildings. The research has been published in the journal Proceedings of the National Academy of Sciences.
The new material is a combination of organic molecules engineered to be transparent in the visible and absorbing in the near infrared, an invisible part of the spectrum that accounts for much of the energy in sunlight. In addition, the researchers developed optical coatings to boost both power generated from infrared light and transparency in the visible range -- two qualities that are usually in competition with one another. The color-neutral version of the device was made with an indium tin oxide electrode. A silver electrode improved the efficiency to 10.8%, with 45.8% transparency. However, that version's slightly greenish tint may not be acceptable in some window applications.
Both versions can be manufactured at large scale, using materials that are less toxic than other transparent solar cells. The transparent organic solar cells can also be customized for local latitudes, taking advantage of the fact that they are most efficient when the sun's rays are hitting them at a perpendicular angle. They can be placed in between the panes of double-glazed windows. [The team is] working on several improvements to the technology, with the next goal being to reach a light utilization efficiency of 7% and extending the cell lifetime to about 10 years. They are also investigating the economics of installing transparent solar cell windows into new and existing buildings. The research has been published in the journal Proceedings of the National Academy of Sciences.
Comment removed (Score:5, Funny)
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It will help cauterize the wounds. So you won't bead to death, but live the rest of your live with massive scars.
It isn't a perfect world.
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"It will help cauterize the wounds. So you won't bleed to death, but live the rest of your live with massive scars."
You mean the time he needs to fall 50 floors to the concrete?
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and speaking of numbers.
86 45 11 03 20
Double efficiency (Score:4, Funny)
If you hold a mirror behind the window?
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Lately I've been wondering if blinds with a reflective outer side would be a good way to reduce the amount of heat entering my home through windows. People put mirror privacy film on windows but having it on the blinds would make it easy to "remove" when not needed.
Presumably it would improve the efficiency of these solar films because they have twice as much opportunity to absorb photons.
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These panels absorb near infrared - invisible light that heats up your house. Sticking it on your south-facing (north-facing for australians, etc) windows should also have a cooling effect on your house. If you have A/C, not only do you get some free electricity, but you can save on A/C costs. Double win. Obviously you would need large windows for this to be worthwhile, unless it was a cheap coating and wiring solution.
Most skyscrapers will have coating to reflect a lot of light anyway, so the lighting leve
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I've never lived in a house with a window replacement cycle that short, and I don't think I've known of any, either. Are new windows getting that crappy?
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Large sunroom type windows sometimes go bad faster than that due to large surface area of he seals around the edges even with a relatively robust seal.
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New windows last a long time, 25 years+. And remodel brands like Milgard will replace failed windows decades later, an actual "life-time" warranty if you manage to keep track of your paperwork and think to contact them.
In old homes the windows started going to shit after 10 years. But that said, I've bought homes where people still had the old aluminum frame single-pane windows from the 1970's in it, a 40+ year old window. People will put up with less than ideal windows as long as the glass isn't broken and
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These panels absorb near infrared - invisible light that heats up your house. Sticking it on your south-facing (north-facing for australians, etc) windows should also have a cooling effect on your house.
Was thinking the same thing, but by absorbing the difference between 8% and 43% (well, less whatever they're reflecting), the panels would heat up pretty good. So, you'd probably want double-paned windows to keep the hot side away from your AC'd air. Unless you live where I do (northern MN), in which case you'd want them on the inside to help with your heating bill. This is the land where triple-paned windows aren't a silly investment.
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>"Lately I've been wondering if blinds with a reflective outer side would be a good way to reduce the amount of heat entering my home through windows. "
Funny, I was just thinking the exact same thing a few weeks ago. In the winter, it could be "reversed" to absorb heat.
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Lately I've been wondering if blinds with a reflective outer side would be a good way to reduce the amount of heat entering my home through windows. People put mirror privacy film on windows but having it on the blinds would make it easy to "remove" when not needed.
Presumably it would improve the efficiency of these solar films because they have twice as much opportunity to absorb photons.
I looked into using reflective window tint to reduce heat coming through a skylight. I read that it could cause heat buildup in the skylight leading to failure. That would be bad.
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Hmm, well I know some people use the film designed for greenhouses on their windows. It cuts UV light and prevents all their printed material fading and plastics yellowing. Great when you want to display them.
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Reflective should be all right, if applied to the actual skylight pane. Absorptive may be a problem if it heats an enclosed space, like between window and storm.
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Reflective should be all right, if applied to the actual skylight pane. Absorptive may be a problem if it heats an enclosed space, like between window and storm.
I think the problem is the reflective tint traps heat inside the double-pane glass, leading to seal failure and potential cracking.
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The blinds just have to be white. The difference between a white surface and a mirror surface is that the white surface scatters the incoming photons.
You could design blinds so they were white on one side and black on the other; in the winter you just flip them around (or rotate them 180 degrees) and you'll get solar heating.
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You'll get solar gain just by letting light into the room, directly heating the building fabric and contents. Just open the blind.
Hanging black surfaces is useful for fast air heating, but circulating warm air close to the relative cold of a window probably isn't good for efficiency. I doubt a black window blind would be a good solution.
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Black blinds or shades next to a window will heat up fast and re-emit a portion of that heat to the glass, which in turn would transfer a lot of it back outdoors.
That heat loss could be managed with emmissivity coatings, air flows, blind geometry, etc., but just letting the sunlight all the way in would usually be better.
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Good point. Why has nobody made this?
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Short answer: Yes.
Blinds of most colors can reduce the total amount of cooling needed for the space, but because they are lightweight and heat up fast, and transfer that heat to the air easily, they can often actually increase the peak cooling load even though reducing the average, at least if less reflective.
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I use thermal blinds on my windows in the summer, it makes a big difference for me. They're made of a honeycomb fabric material, but they're not black-out and let some ambient light through which is nice during the day. And even without something so fancy, putting your blinds down on a sunny day keeps the sun from hitting surfaces in your home and warming them and your house. Better to have the sun heat up your blinds and have it radiate somewhat back outside through the window.
There are windows with integr
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Another way is to incorporate deciduous vegetation in front of the window, like a grape bower - leaves provide shade in summer, then drop off in winter to let sun through.
Windows only? (Score:4, Funny)
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Kernel devs change mind and close with WontFix "Opaque solar panels already verified as working; transparent ones not working will be a userland problem - see shell script for possible workaround."
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They'll work in 6 months with steams "Photon".
Replace skyscaper windows how often? (Score:4, Interesting)
I haven't heard of any proposed pathway for extending organic solar generator lifetimes to long enough that they'll be useful for use in building construction
If anyone knows of even a theory based in chemistry or physics that proposes otherwise, let me know.
Until then, silicon panels with their 20 yr+ lifetime will rule the construction space.
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If they're still working on EXTENDING the useful lifetime to 10 years, then there's no way these get off the ground. (unintentional pun I swear)
Valid point. The monetary cost, and energy cost, of replacing windows in a high-rise is sky-high (intentional pun, I swear). It would cost more to replace them than the profit from energy they produced, and the environmental costs of the machinery to get workers up and down the side of the building would offset that as well.
Unless these panels were entirely on the inside of a normal window, which I doubt is the case.
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You wouldn't retrofit. You'd install them at construction time. Retrofit would not only involve replacing all the panes but wiring them, too. You'd probably need to use microinverters so you could connect them into existing circuits. They are more expensive per watt than normal inverters and now you've got many microinverters to maintain...
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Even if they did get the lifetime up, they'd also have to get the cost down. Since there was no mention of it in the article, it must be so astronomical that it's not worth mentioning.
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Being that this is a scientific research, not an engineering design. There isn't any product associated to it, nor its costs.
Some discoveries like the Blue LED moved really fast in the market from discovery to a product and put into nearly every product it could possibly be in (Including many it shouldn't be in, I am talking to about a lot of devices that are meant to be in your bedroom at night. That disrupt your sleep and mess with your night vision Digital Clocks, Wireless Chargers, Home Routers...) Bu
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Being that this is a scientific research, not an engineering design. There isn't any product associated to it, nor its costs.
It remains possible to make an estimate of what it would cost to put products into the market.
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Advancements don't alway lead to products right away.
There are also a lot of areas where there are breakthrough advances in which a product was never made from it. But what it did was put research onto a new path where a good product would be released.
We still see Scientists as a Scientist, Engineer and Businessman combined. Where a guy can make a discovery, turn it into a product and sell it to make millions!
Where the Scientist may spend their professional life to find a 1% improvement and have it verifi
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Advancements don't alway lead to products right away.
I know this, but where is the advancement? The slight bump in efficiency?
Organic solar panels have been around for decades with very good effeciency, but won't gain traction for this sort of application until lifetimes improve.
Increasing efficiency without increasing lifetime for them is relatively easy.
Increasing lifetime is what everyone has been asking for, and has not yet been delivered. I don't have much respect for organic solar panel researchers that refuse to focus on the right problem.
Indium? (Score:2)
So, who owns all the Indium?
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It's the 49th most abundant element on Earth.
https://en.wikipedia.org/wiki/... [wikipedia.org]
Re:Indium? (Score:4, Informative)
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So, who owns all the Indium?
Indium is produced exclusively as a by-product during the processing of the ores of other metals. China is a leading producer of indium (290 tonnes in 2016), followed by South Korea (195 t), Japan (70 t) and Canada (65 t). source https://en.wikipedia.org/wiki/... [wikipedia.org]
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Indium is produced exclusively as a by-product during the processing of the ores of other metals
I'm sure that can change if there's a sudden surge in the demand for it.
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Indium is produced exclusively as a by-product during the processing of the ores of other metals
I'm sure that can change if there's a sudden surge in the demand for it.
https://en.wikipedia.org/wiki/... [wikipedia.org]
Stupid (Score:2)
Why compromise the orientation and efficiency of a solar panel by also trying to make it a window?
It’s better to have an optimized solar farm where there is space and just transmit the electricity to urban areas. Let windows be windows.
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Though of course a centralized power generation with higher efficiency photovoltaics at the right angles would be a better overall.
However the idea here is not to replace traditional PV application with way less efficient windows. The idea is to replace regular window glasses with glasses that also double as power generators. You can still put PV on your
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Enough? (Score:2)
Will 8.1% efficiency allow generating enough electricity to light up the rooms to compensate for the (100-43.3)% loss of sunlight through reduced transparency?
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How long do they last? (Score:1)
Insanity (Score:1)
Why would I need a solar power window, if I can install solar power walls more cheaply?
been there, done that (Score:1)