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Solar Window Panes
Val42K writes "Now, those windows that allow glare onto your computer screen can be useful. They will provide power to your computer, air conditioning and other useful necessities. Energy conversion rates are 'way more than 50 percent'."
well I kinda wondered about how it would work so well in NY cuz some buildings or in the shadow of others. Second, if this gets implemented and than a couple days of no sun pop up wouldn't it stress out the grid a bit more than normal
uh, so how much do I need to power 5 desktops, 3 laptops, and a server? I hope I have enough windows.
-Tim Louden
Make sure you don't buy Microsoft Solar Windows. Criminals have an easy time breaking in with Microsoft Windows installed.
Windows will actually be powerful? Someone should tell Microsoft about this!
because they will get sunlight devoid of energy. (Just as water downstream of dams has no energy left).
New year Resolution: Don't change sig this year
If I understand this right, we don't necessarily have to put these in windows to use their power. They could be railings on walkways, desks, sculptures....lots of possibilities.
Maybe someday everything we build will take solar energy.
This looks pretty cool, but reading through the article I don't really see exactly how much eletricity these will produce per window. Will they make a significant dent in the power costs for a typical household? The cells may only be a quarter each, but how much will it cost to embed them in the windows and collect the power?
Twenties Retirement
Let the jokes about windows powered computers begin.... I'll start: I want to be the first to have a "linux box powered by windows".
A window, that isn't on my screen, hmmm.....Oh, you mean my outside awareness portal.
"Much work is lost, for the lack of a little more." -Edward H. Harriman
seeing as how many seem to live in glass houses...
I don't really trust Windows to power my computers.
hey!
Check out the pictures to the left of the main story. There's a noticeable difference in light intensity between parts of the window with clear glass and those with the embedded miniature solar panel, leading to a mosaic light pattern. This sort of thing is fine (and maybe even artsy) for an office foyer, but won't be widely adopted in office windows (which make up the majority of downtown buildings) because it's horrible for reading or working in. Your eyes can't tell if they should adjust for the bright or dark spots.
The bold print giveth, and the fine print taketh away
Windows is a pane?
to power my flying car. Seriously, are we to believe that they are producing solar cells aproaching 100%efficiency in converting sunlight to energy, when the one's they use in our spy satellites only approach 35% ? I hope it is true , but seems like it could just be a publicity stunt fishing for venture capital. I mean it is alot easier to raise money once you get your story published in the mainstream media.
I'm a little skeptical of the technology. It seems like they are just repositioning solar panels in a novel way so that they are integrated into the existing decor. However, the best common solar panels today are only 20% efficient and the common ones you see on houses are only 10% efficient. For the researcher to generally state 'way more than 50%' rings alarm bells in my head.
Does anyone know why these would be so much better than existing tech?
-Ryan
AUWYHSTOT (Acronyms are Useless When You Have to Spell Them Out Too)
I don't believe this story for a second. Not a bit.
For decades I have been folowing solar cell technology, absolutely salivating at the promises that efficiency rating would soon rise above 15%.
Well, I've given up. I've read shitty pie-in-the-sky stories like this almost every year for the last 25-years.
Now, if someone on Slashdot tells me that they bought these +50% efficient solar cells in Home Depot, that's when I'll get excited. Like I'll get excited when Chevrolet markets a flying car or my city puts a nuclear fusion power plant into service.
Chill out guys, it ain't real 'till it's real.
--Richard
If the energy extracted doesn't come from the visible light spectrum, and the material doesn't interact with visible light, it will simply pass through unaffected. Seeing as how UV light has much more energy per photon than visible light, this seems likely.
-Ryan
AUWYHSTOT (Acronyms are Useless When You Have to Spell Them Out Too)
Do a Google search on solar cell window and you quickly realize that this is an old idea.
Absolutely. Very old idea. However, do a Google search on commercially available products in this space and you quickly realize that this an old idea that hasn't really been commercially developed. You could chalk that up to the dangerous imprecations of the 'old girls' network, but I think it's just a problem that hasn't been solved yet in a cost-effective manner. Which is why money is still being spent looking into it.
But what's important this time I guess is that it's a woman who "discovered" the idea.
I don't see why you would conclude that. I can think of two reasons this article might be important:
Note that those two options are not mutually exclusive.
Bullshit. Current conversion rates are about 18%, and haven't changed much in 20 years or more; they've slowly managed to squeek out more and more power getting up to the current 18-20%, but nowhere near 50%. Let's put this in perspective- it would be like someone claiming they could get 100mpg in their car, and "easily 200mpg".
The bullshit-o-meter goes off the scale at the claim they can get "100%"- and there's one very simple, indisputable reason; the glass itself blocks a significant amount of energy- ESPECIALLY at a low angle of incidence, where the outer glass is going to reflect a large percentage of the light hitting it. The modules inside the window may pivot, but the outer glass doesn't.
The bullshit-o-meter EXPLODES at the nice little bit about how they won't discuss specific energy conversion rates in detail. It doesn't help that this is being published in Science for People Who Think They're Trendy(aka Wired). Ring me when she's published results in Nature or (gasp) a professional journal.
Oh, and if I wasn't pessimistic enough :-)...if this actually DOES pan out...just wait until you see the price tag on 'em, because I'm sure she's going to patent absolutely everything out to wazoo, and one company will get exclusive rights. It'll also be years before we see 'em, as said company will want to protect its investment on current solar panel technology...
Please help metamoderate.
Um, yeah right.
Even 50% is staggering. Heck even 35% would have been quite impressive. Why is my BS meter hovering around MEG right now?
Don't get me wrong, I know they work and are real but I seriously doubt the efficentcies they claim.
Ah, this must be how they make blacklights.
The bold print giveth, and the fine print taketh away
There was going to be a Linux version, but SCO wanted $700 for each pane.
"There is no teacher but the enemy."-Mazer Rackham
I've done a great deal of research on the topic of solar energy and have a pretty good understanding of physics. To the average person, this article sounds wonderful - super efficient solar panels, a total breakthrough! To me, it's pretty easy to see this article either grossly misquotes the researcher or the researcher is completely crazy.
From the article: "Ultimately, Dyson is confident her team's solar cells can reach nearly 100 percent efficiency -- compared with typical solar panels' conversion rate of less than 20 percent."
100% sounds great. Except they forgot that glass absorbs/reflects a minimum of 10% of the light, much more at non-direct angles. And that getting any semiconductor (solar panel) surface to absorb all light hasn't yet been possible - assume another 15% is lost here. And of course, to be able to actually see through the cells (they're "translucent"), we'll assume 20% light transmission. Then you need to think about things like entropy and expect a nice loss in this process, we'll be generous and figure 10% loss.
Just adding the percentages shows 55% efficiency by simple addition. And this is with everything ideal. And now consider that the _best_ solar experiments have approached, under super-controlled situations, 40% efficiency.
And top all this off with no demonstration of the product itself and no details on their technology, it's another vaporware article.
Both. Take a look at the pictures that go with the article. It looks like each 'solar chip' has a largish fresnel lens that focuses sunlight onto the chip. The lens/chip assemblies appear to track the sun, and you can look past these and still have a relatively clear view as long as you're not looking in the general direction of the sun (which you're not supposed to do anyway). The lenses provide shade by focusing sunlight onto the chips, but they also allow ambient light to enter, so a room fitted with these solar windows would still get plenty of light.
Cool.
The glare that once bounced off your computer monitor no longer exists. And the sun's intense heat, which once led to window-shade tug-of-wars with co-workers longing for a little natural light, no longer beats down on you. You comfortably tap at your keyboard under natural, abundant, ambient light.
Do the math...one cm^2 out of one ft^2 still leaves 99.9% of the area uncovered. How does this stop glare or solar heating?
In the article it states that the squares are translucent, but solar cells appear dark in color because they are asorbing energy and the silicon that it is stated they are made of isn't transparent(at least the last time I checked) unless they adapted the formula for transparent aluminum.
If these chips were actually 50% efficient wouldn't the target application be either large scale solar energy collection or satellites or something, not automatic window blinds like stated? Satellite companies would jump all over this if it were true. Some of the best GaAs triple junction cells are only around 30% efficient. I would really like to have some more information about the actual junction(s) used within the silicon.
If they have the technogy for these suposed
"Dyson is confident her team's solar cells can reach nearly 100 percent efficiency"
why are they limiting it to some silly
window apllication, the cells on there
ones are worth a fortune even at
"more than 50 percent"
I meen we are talking massive incress
from the current "super high levels"
of around 3x%..
http://www.you.com.au/news/1958.htm
Perhaps they are misinterpting the
results becasue of the " focusing them into the small silicon squares, also called solar chips"
maybe the failed to take into account
that if you focuse light onto a cell,
it dosent have a higher output because
its more efficnt, but rather becuase it
has more sunlight on it.
You have 5 Moderator Points!
Which Helpless Linux zealot/MS basher do you want to mod down today?
And they do help with temperatures a lot here in Texas. I also have a very dark shade put up in my room also to keep the light out. Ahh the sun *hisses like vampire*
Funny, I was just thinking about something like this.. My idea wasn't transparent though. Generally, office windows are too big, and frequently blocked by furnature. 8-foot tall windows do give a pretty good surface area to work with.
What if....
Take a reasonable area of the window, and mount solar cells and peltier elements flush to the window. Admitted, it won't work on all sides of the buildings, but 50% of most buildings could use it.
The solar panels aren't enough to say run the whole office, but they would be good for powering the peltier elements, and supplementing the building power. Say it took 25% of the load off the building, that would be substantial.
Peltier elements are usually good for a 70 degree difference in temperature between the front and back of the element. So, if it's 100 degrees on the hot side, it could be 30 degrees on the cool side. Ahhh, on a 100 degree day, wouldn't it be nice to be in a cold office?
Many buildings (architects can argue this all day) have a decent space between floors, for ducts, plumbing, power, and the thickness of the floor itself. The outside of the building in those spaces is unused non-window space. If the buildings, by design, used that space for solar panels, and used peltier coolers as part of their cooling system, cooling at least part of the outside surface in the summer and heating it in the winter, the power reduction would be tremendous.
Most of the buildings I've worked in for long durations were in the southern part of the US. Those buildings usually require cooling year round to maintain the appropriate temperatures, thanks to all the hot equipment we run inside.
Just my thoughts.
Serious? Seriousness is well above my pay grade.
and it does reduce the heat in my 'radio and computer shack' by about 4 degrees during the day. I have 150W of solar and they charge batteries and those power the UPS and 12VDC equipment like radios, netgear switch, and SMC router. When the sun comes up the load comes off of the battery charger and the temperature goes down= do not need at much cooling. It is about 100W/hr of cost savings at full sun.
She is leading a team of researchers who are trying to prevent future power failures by making energy-sucking office buildings ultra-efficient at peak hours. (From the article)
I'm here working, and I am the only one on a floor that holds 200, and EVERY light in the place is on. Also all the other 6 floors of the two adjacent buildings are running. What's worse, I couldn't even tell you how to turn off even a section of these lights, as there are no visable light switches. My company is just wasting power... All I really need at my desk is my two lamps and nothing else.
Whose time has come. Put solar windows in all office blocks, and solar tiles (both electric & water heating) in the roofs of all houses, and you go a long way toward solving the energy problems. Even in cooler countries these schemes pay-back after a few years - ie the extra it costs is paid back in electricty savings. In hot contries, a house can (in effect) generate as much electricity as it consumes - in Australia you have Zero annual electricity bills for these guys - the tiles make as much electricity as they take from the grid. (ok with gas heating, but the hot water supply is provided by the sun too). Check also This link, This link , This link or This link.. Want a large scale plant? What about the deserts of the world ?
Combine with Wind power, and other alternatives, and we may get 100% of our energy needs without nuclear, coal, gas.. What do you do when you have excess off-peak power? Turn it into hydrogen for your car!
Read more about it here..
"You lied to me! There is a Swansea!"
The idea isn't that different from Fritted Glass, where you have ceramic paint on the window to reflect some light and reduce the solar heat load (or just for privacy). Any glare on the screen is bad, and makes it difficult to focus; the pattern might make it slightly more manageable.
I think the scale of the cells shown in the renderings is a bit off; you would actually get more usuable surface area with "dots" rather than "small panels", and it would be MUCH less obtrusive.
This article is clearly a pie-in-the-sky dream.
... including Persian Gulf defense prior to W: $35.2 billion
Solar power, however, isn't. There is a lot of promising research in the field, and higher efficiency panels are possible (over 20%, not near 100%). But research continues on shoe-string budgets.
Some rough numbers:
Yearly direct oil industry subsidies in the mid 90's: $11.9 billion
W's proposed budget for developing alternatives:
solar: $42.9 million, wind: $20.5 million
These numbers were found with google and shouldn't be taken as gospel truth, though I believe they are roughly accurate.
I seriously doubt her claims of possibly being able to reach 100% efficiency out of a solar cell. The current maxium possible efficiency that can be produced is about 30%. "Actual" efficiency is usually closer to 25%. New research into multilayer indium gallium nitride cells could approach a theoretical 70%. (50% for a 2 layer cell") My primary concern here is just how many watts these windows will pump out per dollar, cuz if its much over $6-7 a watt, I wouldn't expect many people to purchase them.
Non sequitur: Your facts are uncoordinated.
The solar chips, probably about a centimeter or so square, would be spaced inside a square foot of unfiltered window. 1CM^2 gets at most about .1W, and that's momentarily at "solar noon", dropping off fast. A giant window, say 10x10', could collect a theoretical max of 8W, which wouldn't be enough power to even blow the inside air along the inside surface of the glass, let alone cool it.
Plus, any "near 100%" efficiency claims for wideband (sunlight) transduction are suspect, as even the best narrowband microwave transponder pairs are at best ~90% efficient (and very expensive). Then consider how that 100% efficiency contradicts the statement that they are "translucent", and I wonder why I even bothered to justify this insipid report about a (solar) fusion scam with a post.
--
make install -not war
This nice bit of technology (but bad engineering) will never make it in the real world. Pigeons, spiders, wind, snow, urban grime, clumsy cleaners, and assorted urban insults (taggers, vandals, inquistive slashdotters, etc.) will doom any of these solar window installations to the scrap heap inside of a year or two. Their structures look far too flexible and intricate to survive real world applications.
Don't get me wrong. I would love a cheap, reliable source of solar power. And I don't care about efficiency, because it is only tangentially relevant to the real measure of solar cell feasibility. I only care about long-term TCO and the effective ROI. Give me a coated, 5% efficient solar cell plastic film that costs 10 cents per lifetime kWh and I will coat every square inch that I have ownership of. Until then I will say "just what I need; another complex costly subsystem on my building."
Two wrongs don't make a right, but three lefts do.