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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!
First it says the squares are translucent. Then it says they don't impede the view. Which is it?
Twenties Retirement
there are a lot more roofs and walls than windows and roofs are better situated wrt the sun. Therefore photovoltaic roofing would always be a better idea.
I didn't think the sun had anything to do with Windows being a pain!?!
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.
We already have a lot of promising technology related to alternative energy, energy transmission, and energy conservation. However the common problem amongst all of these is cost. People are usually cheap and until the ROI becomes better businesses are not going to do it. However ROI calculations are becoming easier to make as costs drop as the technologies progress.
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".
what do the feng shui people think of this?
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
i'm confused. the article says that these are one cm^2 every 1 ft^2, and then says that they don't obstruct the view.
i'm fine there, but what gets me is, the article then says that this will eliminate the glare on monitors. with a cross-section that small, how could it eliminate *that* much light?
Do a Google search on solar cell window and you quickly realize that this is an old idea.
Korea's into it.
Oberlin too.
Apparently, Durham as well.
But what's important this time I guess is that it's a woman who "discovered" the idea.
And because women are equal to men, an equal number of discoveries must be credited to women.
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 makes me glare.
Ha ha, jjeffries you old wit -- you've done it again!
never thought I'd see the day Slashdot praised Windows.....LOL
seriously, though...energy is everything we need...from producing food to finding water (or desalinating the oceans as will probably be necessary) we need energy to make this work....
therefore...this is a very good thing...esp. taking buildings off the grid...
on the other hand, if this really does hit 80-100% efficency as predicted in the article by scientists, I can see a lot of servers and CO-LO's relocating to the Equator...LOL
pax
RB
----------
ah honey, we're all resplendent - Bill Mallonee
How can the window both let the light trough and get energy from it? I really want to see the technology behind that bit of genious. I understand how a dam uses the movement of the water for energy but to suck the energy out of light is blowing my mind.
-Tim Louden
Why not cover the outside of the buildings with the solar disk and leave the windows for what they were ment for...pressing our faces against while we are convinced someone else is having a better time out there.
I eat my grapes at room temperature, cuz the cold ones hurt my teeth
Should this even be legal??? It's like when GM bought and decommissioned all the trolley cars to further their monopoly!
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.
They say that if you put a Windows install CD in backwards you hear satanic messages. But the real scary part is that if put in forwards, it installs Windows.
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)
And they're all flakes. I went to RPI, and the architecture people, the ones who stayed in, delighted in designing buildings that wouldn't stand. The real builders became Building Science majors and or Civil Engineers. 'way more than 50 percent' efficiency sounds typical of the culture there. Spin, FUD, esoteric crap, let the Engineers figure out how to make it work.
I want to delete my account but Slashdot doesn't allow it.
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
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.
What ever happens to these cool sounding 'free' energy things? I've read countless articles in Wired and other magazines that never seem to come to fruition. I seem to remember things like this in the past but never see them when I look out my window...
As a rock-in-roll Physicist once said, No matter where you go, there you are.
I'm all for saving money for one, less pollution, and putting the filthy, greedy bastard electric companies out of business.
I'm tired of being ass raped every month with a broken bottle and a pound of sand.
My last electric bill was $195.00
$85 was my actual usage and the rest was a "Cost of fuel adjustment"
Well Entergy, adjust this up your ass. Your days are numbered. You are a dinosaur and we will bury you like the dinosaurs.
Free, clean energy for all..
Mod Parent -1 Stupid
At least in the summer, it wouldn't be a problem if it was cloudy. With no sun out heating up the building through the windows (and walls), air conditioning costs would be considerably lower. And of course, since A/C is the biggest energy drain on the grids in summer, it shouldn't be a problem at all on cloudy days
The sending of this message pretty much inconveniences everyone involved.
If by some miracle that claim is true, it could change the world. People have been striving for decades to eke out a couple more percent efficiency out of solar collectors. This would be a major breakthrough. The last thing anybody would worry about is sticking these >90% efficient cells in a window shade; they'd be deploying massive arrays of them in the desert for power production at costs below conventional power plants.
However, since they seem to be focusing on windows, something tells me that the claim is less than accurate.
Instead of absorbing energy from light passing through windows (and reducing the amount of light you get in your building), why don't you put solar cells around the windows on the outside walls. Or on your roof... This seems like a complicated way of generating electricity when a similar simple solution already exists.
DO NOT WRITE IN THIS SPACE
okUm, 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.
Thats why it is important. Wired is covering it.
NarratorDan
Ah, this must be how they make blacklights.
The bold print giveth, and the fine print taketh away
I worked for years at the Solarex plant in Virginia that pioneered trying to make thin-film photovoltaics cost-efective. Our corporate parents finally pulled the plug last year when our latest amorphous silicon demonstration project came up with a 41% efficient panel that cost much more per watt to produce than nuclear. Now the only place you'll find them is on a few Coleman campers and a gas station pump island awning in Indiana.
Thin-film technology held a lot of promise, but that's all it was. File it away with global warming and cold fusion under "BS".
Scruting the inscrutable for over 50 years.
There was going to be a Linux version, but SCO wanted $700 for each pane.
"There is no teacher but the enemy."-Mazer Rackham
"Ultimately, Dyson is confident her team's solar cells can reach nearly 100 percent efficiency"
I hear they don't insulate too well either, what with the holes popping up all the time.
I am a viral sig. Please copy me and help me spread. Thank you.
The wired article is pretty cool (but I'm sure I've read about this before; maybe Discover magazine in a R&D section?)
I wonder how much it'd cost to do my house. ^_^
Okay, put me on your foes list, McBride. I hate your fucking guts.
Fuck Beta. Fuck Dice
I'm seeing a few posts mentioning clean or environmentally friendly power. After production solar cells do give you that, however the last time I check the production of solar cells resulted in large amounts of toxic material. They probably end up being better then coal plants but not as clean as nuclear or my personal favorite solar heat plants. This isn't meaning to sound like a bash. I fully intend to use solar cells on my new home, I just wanted people to realize that nothings perfect.
As for the article, as others have pointed out, those efficiency rates are too good to be true. However I remember hearing that some key patents on solar cells are close to or have already expired. Perhaps some of those methods have allowed for some gain. I truely doubt that 100% is ever going to be possible, and I'd be happy with 35%.
psxndc
The emacs religion: to be saved, control excess.
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.
Depending on the bulk of the equipment used in the conversion process, I wonder if perhaps this technology could be applied to electric vehicles. As long as such tiny windows could actually collect enough energy to make it worthwhile, that is. With the claims of > 50% conversion and the cells being translucent, perhaps it could work.
Random idea... probably insane, probably retarded. I never didn't claim to be either. Or both. What was the question?
It goes from God, to Jerry, to me.
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.
For now let's just try to achieve a slashdot free of fucking imbeciles like you. You can take the first step.
However, it appears that a lot of light gets through, so by no means could it be 50% of the light that the surface is is exposed. In contrast, a regular solar cells are opaque and therefore their percentage is out of 100% of the light that they are exposed to (sounds a bit harder, to me).
I've read that part of the problem with solar cell efficiency is that they only use a narrow part of the light spectrum. So, I guess the light that doesn't make it through these transparent solar cells is more likely to be used to make electricity and gets filtered out in the process.
Sdelat' Ameriku velikoy Snova!
It makes sense to me that the real the real reasons for technology like this are to diversify our power grid. No one thing is going to make a huge dent in our power needs, but if we can spread out where we get our power from or even decentralized it then if one power plant goes out or has to cut back on production the whole thing will not overload and shutdown. So I would view this as just one step in strengthening out power grid.
What's wrong with this picture from the taxpayer's perspective?
~.~
I'm a peripheral visionary.
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*
Both on a whole are generally vapourware..
Lots of spin associated with both..
If they ever get off the ground, they deliver only about 20% of what is promised..
It's going to be left to some poor development people to try and implement some impossible idea that some marketing wanker was claiming...
Doesn't take much to show that both are highly broken...
Both need almost weekly cleaning..
Each stops working in 8 hours or less and needs a daily restarting...
Each is a rip-off of other people's ideas - and poorly implemented...
Lots of incorrect positive rubbish gets written about them in Wired...
Patents Patents Patents....
and
There are much better ways already out there of doing what they claim.
We can't even get really, really expensive solar cells (like on SS Alpha) to get near 50% efficiency. Like cold fusion and anti-gravity, this has yet to be figured out. Slashdot has jumped on a hype for something that doesn't exist.
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.
i was just wondering if these panels convert light at an efficency of 100% then one can't use it as a window since no light is coming thru, because it gets converted 100%, yes?
...
so convert the light 100% then use the energy to make light in your super-dark office
I GET IT!
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.
1) A good chunk of the solar spectrum is in the mid-IR and UV. I dont think this is recoverable even by a multi-layer solar cell
2) to beat the reflection loss the outer pane of glass, the focusing lens, and the solar collector will will have to have zero dielectric reflectance across the entire solar spectrum. For the outer pane, which wont be rotating, this also has to be true at all incidence angles. Otherwise each of these surfaces is going to have a reflection loss which ought to be a minimum of roughly 4% per surface = 20% loss.
3) the multi-layer solar cell is going to have multiple DC output voltages that need to upconverted from fractions of a volt, to, presumably, 120v AC. This is not lossless. Presumably each solar cell will have to do this converison itself, since lashing them in paralllel is likely to be fraught with the problem of them fighting each other, like bridging tow batteries with different voltages. (e.g. bird poop blocks one of the cells, and it voltage drops.).
4) any loss in the solar cell means its going to start heating up. so there may have to be some sort of airflow in the widows to cool it. If this is active cooling theres a loss.
there's also some technical issues. if you have a phased array of mirrors, and they malfunction its possible you could create a building sized lens reflecting the sun in some direction. Even when its working correctly it will reflect back towards the sun. I wonder if its possible this could create a hazzard to other building and planes or pedestrians?
Some drink at the fountain of knowledge. Others just gargle.
I don't worry about glare. I live in a 2 story house on the dark side of the moon. The only glare I get is from my wife, which is better then getting glare from my girlfriend. I have a girlfriend for sex, not glare.
Energy conversion rates are 'way more than 50 percent'.
... will have a "way more than 50 percent" energy conversion rate.'
This is a misquote of the original article, which says:
'The cells
And even that is obviously hot air from a marketing droid. I'll believe
a conversion rate above 25% when a reliable person reports having
measured it, not before.
Someone please categorize this in the SNOWES section.
(Shit No One Will Ever See)
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.
How much energy do these things take to make. If you ever ask a solar panel manufacturer for a Life Cycle analysis of energy they go very quiet. Most solar panels cannot produce as much energy over a reasonable amount of time as the amount of energy that went into producing them. To be fair technology has been getting closer and closer to the 'ignition' point (to steal from the fusion people), and of course this varies depending on whether you are in Arizona or Aberdeen. Until then solar panels have their uses but they will be not be paying their way as far as generating new sources of energy until the energy it take to manufacture them is brought down.
Maybe the poster remembers Wired when it was new, years before Conde Nast bought it, because comparing the two, the "new" Wired is absymal.
When Wired started out, a lot of us liked it and started reading it, because it had some of the geekiness of Mondo 2000 and boing boing, but without the fake fashion layouts and somewhat less emphasis on drug culture, "smart" or otherwise. It even had some of the same writers, but weeded out most of the silly ones quickly enough. Oh, and it just looked like something progressive and promising that you wanted to pick up, too.
I remember reading a serious article about global economics in an early issue. Neal Stephenson also wrote a story/article for the magazine. What do you find today? Advertorials? Shopping guides?
Wired is the new Omni, except there's probably even fewer (intentional) fiction pieces. All that's missing is a binding change and a glossier cover - are they running a monthly contest in the back yet, just like Omni did?
Get off my launchpad!
Dyson said a single solar cell will cost about 25 cents. The cells are situated about a square foot apart and will have a "way more than 50 percent" energy-conversion rate, she added.
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.
I also recently started researching this photo solar stuff and I am pretty damn sure that my cells will have 110% efficency. And they will do the dishes too.
bla bla, bla bla
-r
Dyslectics of the world, untie!
Just another attempt at profit via government funded R&D. Congress regularly mandates money for crap no expert wants. "Voted for alternative energy" vs. "voted against alternative energy". Its the micromanagement disease. Left up to the experts at DARPA, these jokers proposal would hit the circular file before the ink dried (how about deleted from the in mail folder/directory before half read?)
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!"
We are already seeing that the US army is struggling to put enough forces into Iraq to stabilise the situation and get the oil flowing. What happens if there is a fundamentalist coup in Saudi Arabia, and a war with Iran? And if Putin decides that now is the time to reassert Russian power and decides to supply all the oil to the EU? Would the threat of a nuclear attack get the oil flowing again? Are conventional forces big enough? The result of the attack might be even worse (discontinuation of supply for years.)
The probability of that may not be huge, but it actually represents a credible threat to US power. I suspect that the US is far less well equipped to deal with a repeat of the early 70s than it was at the time, because the dependence on imported oil is so much greater and so much population movement has taken place into areas with more difficult climates. The effort to stockpile oil is limited because diverting more oil to stockpiles puts the price up.
If the US economy did not require so much energy just to maintain energy-inefficient buildings, the strategic position would be better. In a war you can require people not to make inessential journeys, share transport and so on, but you cannot make them work in unendurably hot or cold offices with unreliable power. Bottom line: in the long term, this kind of thing is part of long term military strategy, and the budgeting should take this into account.
Panurge has posted for the last time. Thanks for the positive moderations.
>|<*:=
I read in Scientific American some few years back about amorphous silicate solar cells -- basically, solar cells on glass. Efficiencies were much lower than standard silicon based solar cells -- the microreceptor failure rate was much higher, but the cost per square metre was not a lot more expensive than ordinary window glass. Has anything been done in that direction lately?
Do not mock my vision of impractical footwear
There's a sticker on my computer that says "Powered by Windows", you know...
He gave us uranium and plutonium...
And for that matter, tell me where it mentions light bulbs or PCs anywhere in the Bible. Just because it's not there doesn't mean it's not un-Christian to make it.
-uso.
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.
Here is what I think they did to come up with ">50%" and "~100%". Take the same cell, put it behind a Fresnel lens with the chip at the focus. Put that assembly behind an office window. The lens focuses the meager transmitted light from a .25 square meter onto the chip, and the chip emits 40 watts of power. Poof, we declare it to be 100% efficient, never mind that the collection area is not some small number of square millimeters, but rather 250000 mm^2.
So, under this scheme, % efficiencies of the chip become meaningless, and we have to instead talk about the efficiency of the system, cost of the system, Return On Investment of the whole. And these are squishier numbers, and more mind-numbing, and easier to fudge.
Putting a cheap Fresnel in front of an expensive chip _is_ interesting. You can use refraction to separate the concentrated light by color; your chip probably only cares about a small range of the rainbow, and blasting it with concentrated sunlight from colors that it doesn't convert probably just shortens its life. So sending that light somewhere else is good. (A Japanese company was making very expensive systems that did something like this, but instead of sending the color-filtered light to a photovoltaic, they sent it through a light pipe into your home/office/etc. They were interested in discarding ultraviolet and/or infrared. Don't know if they're still in business - they seemed very "boutique".)
Since Peltier elements are semiconductor devices, as are solar panels, you could probably bake these all at once. Great idea.
Now you're just tiresome.
Humans are called to be stewards of Earth, which means we're to keep the planet in good condition. Solar power helps us do that by reducing pollutants from fossil fuels etc.
Chickens eat corn, and we eat chickens. Does that mean we shouldn't eat corn? Your 'natural order' is rubbish. It's people like you that make true Christians look like mindless fanatics. That's not to say that there aren't Christians like that, but you're not helping the case of us who are not.
Insightful my ass.
Can't you recognize a troll???
Glory Network Auspicious Achievements irc.efnet.net #gnaa
Umm, Gnaa?? more like Gay n***** Association of America.
You'reofftopic and a response to a troll, you should, along with this message that is already at 0, be modded to 0 or -1 for off-topic
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.
To be fair, you probably don't hear the readers of Wired saying much of anything, since a magazine is by nature a one-direction medium. Letters to the editor notwithstanding, that is.
--grendel drago
Laws do not persuade just because they threaten. --Seneca
Background: Photovoltaic cells are essentially semiconductor diodes with huge junctions exposed to light. Photons hitting the junction area can create electron/hole pairs, which migrate to the N and P sides of the junction respectively. The charges can either recombine through the junction or be drained off through external connections. The problem is that a junction has one and only one operating voltage, and if a photon is absorbed pretty much all of the energy beyond that required to create the electron/hole pair becomes heat. Photons without enough energy to create a pair tend to sail through the cell.
The stacked-junction cell exploits this low-energy transparency to reduce the losses. A high-energy band gap cell is put on top, and it skims the highest-energy photons and lets the rest through. Below that is another cell made of a material with a smaller band gap, which grabs some of the photons at lower energies to make more electron-hole pairs... and passes the rest through. Lather, rinse, repeat.
To get really high efficiency at reasonable cost, you'd have to have the following:
- A whole bunch of semiconductor materials suitable for PVs.
- ... which have compatible chemistry and crystal structures.
- ... and have band gaps at just the right spacing that each one can grab a roughly equal fraction of photons in the incident light (whose spectrum changes with time of day).
- ... and can be deposited using cheap equipment that runs fast.
Just one or two of these requirements is a fairly tall order, as the PV market shows. Satisfying all of those requirements at once isn't going to happen for quite some time, and anyone making marketing claims is blowing smoke.Time is Nature's way of keeping everything from happening at once... the bitch.
Whee, someone was already working on a better version of an idea I had a few months ago. Yay! My idea was much clumsier, and was designed to make buildings look a little like trees, with branches and leaves. But her idea is much more efficient and attractive, and still heliotropic. :-)
Need a Python, C++, Unix, Linux develop
If you are talking about overall energy consumption, you might well be better off by making some of those steerable PV thingies into little mirrors. You aim the mirrors to bounce sunlight back up and off the ceiling, which replaces the need for overhead lighting and all its electric consumption and heat generation.
Time is Nature's way of keeping everything from happening at once... the bitch.
They still like to throw stones though ;-)
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
80 odd percent conversion efficiencies from panels and tubes, and, heat is much easier to store than electricity.
Government of the people, by corporate executives, for corporate profits.
Windowpane! So much better than 75!
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.
If I use that same mirror to bounce that same 100 watts of light in through a window and, say, a dichroic mirror which reflects the 50% which is infrared and keeps it outside, I lose 50% IR + 10% of the remaining visible light and get 45 watts of light. I have no hardware costs for the generator and my lamp life is increased due to being used less. I've replaced at least $150 in generator hardware and kept 105 watts of heat out of my building, which I don't have to pump out again. (If I need heat I can always slide that dichroic mirror out of the way.)
From this I conclude that even in hardware, sometimes less is more.
Time is Nature's way of keeping everything from happening at once... the bitch.
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
> there is an unrelated company called GroupSoft.
And there's also an unrelated company called Big Fun Balloons, what's your fucking point?
I can't think of anything more Offtopic and Flamebait worthy. This entire fucking thread should be modded down to -1.
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.
A couple of us revolted last year and found a switch combination that only put about a third of the office into darkness, but the boss nixed it soon enough.
I would love to be able to kill all of the lights above me (probably about 400W per employee) and use the ONE desk lamp.
I've done a little research into solar energy production and know a bit about physics, also. Here are some of my thoughts.
What mechanism actually prevents solar cells from reaching 100% efficiency? I mean, is it a natural physical limit, or is it merely that they haven't been engineered sufficiently to take advantage of all of the light that falls on them? I'd guess that it has something to do with making cells dense enough to capture *every* photon that lands on them.
If that's the case, then there are two ways to increase efficiency, based upon how it is defined:
In normal scientific terms, efficiency would be defined by the amount of energy that is converted compared with the amount of energy that is incident. That's science.
In economic terms, though, efficiency has a completely other meaning. A cell's efficiency is determined by the (manufacturing/maintenance) cost versus the energy converted.
In pseudo-marketing hogwash, the two definitions could be combined. The 'efficiency' of a cell (just the small, *expensive* part that does the conversion) could be defined as the relationship of the size of the cell (and thus the majority of the cost) versus the amount of energy that it converts, regardless of the amount of energy that is incident on the entire system or it's size.
In hogwash terms, a *concentrating* cell arrangement such as this could have 4x the efficiency of a 'normal' solar cell merely by increasing the incident light that falls on the actual collector, the small cell in the middle.
This means that it is actually more *economically* efficient because the most expensive part, the silicon collector, has been substituted with a large area of fresnel lens. It also means that it is, in actuality, no more *scientifically* efficient than other silicon photovoltaics because the *total* incident light on the system is larger.
Here's a good link to a functionally similar inflatable frensel lens design that NASA is using on satellites.
"I assumed blithely that there were no elves out there in the darkness"