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Clear Solar Panels Double As Projection Screens
EnergyEfficient writes "Metropolis Magazine has an article about a company that is producing transparent solar panels. The panels 'can generate 3.8 watts of electricity per square foot, an above-average level of efficiency.' They come in a thick version that can be used for glazing buildings. Imagine if all those glass skyscrapers could also produce power! As an interesting aside, they can also be used as screens for projection TV units."
Wonder if they are more efficient than the solar panels mentioned in a previous /. story?
- Danny
It's nice to see that projection technology will be getting cheaper, what with the integrated solar panels and all. Wait, how much do the super-efficient panels cost? Oops...
It would be cool if it didn't suck.
"I know, we'll make a solar panel that lets the light just go right through it! What a great idea!
Is it fascism yet?
And how much energy does it take to produce a single square foot. There is a basic falicy that a lot of folks seem to miss. Like the fact that you burn more oil to create an equivianent amount of ethanol from corn. There is a study at cornell that shows this. The same thing holds for all current forms of solar energy. While it will no double have niche applications, it's not going to release the world from dependence on oil, even if we could plater all the skyscrapers of the world with it.
--- http://davidnehme.blogspot.com
Most glass is mounted vertically so it will only be good in the mornings/afternoons.....
Unlike horizontally mounted stuff which is good at night?
The point is that you can use it with projector TVs. The light from the projector creates the power to run the projector, duh! I'm running over to walmart to buy one for my for my fan powered sailboat right now.
There are lots of interesting things that could be done to produce more ecologically friendly buildings.
The first is simply to make more efficient use of natural light! I stayed for a week in a new residence building at The University of East Anglia (Norwich, UK) and the building really intrigued me. It had hollow lighting columns running up to the top of the building, despite being a rather tall apartment. So there was natural light from the top reaching all floors. That definitely saves lighting costs.
So with approaches like that (using natural light as much as you can) coupled with clear solar panels, you could both use natural lighting and collect power for electrical lighting later on. Improve actual lighting with high-efficiency (85% +) white LEDs (last forever) or high efficiency fluorescents, and you've got one amazing power-efficient building.
The problem is that these supplies -- solar panels, white LEDs have large initial costs. As these costs come down we'll see lots of nice new interiors. I can only expect such things to become more common as people actually realized they're screwed for cheap power.
This is great since mornings and afternoons are the usual peak periods for electricity demand.
Let's take a super-skyscraper, assuming a 200' square base that's as high as the Sears tower (roughly 1450' to the roof top). Assuming the building maintains its rectangular cross section from the ground to the top gives us an area of 1.16 million square feet which would generate ~4.4 megwatts of electricity, which is a lot of electricity.
The article calls out a price of $45 per square foot, making the solar panels for such a building cost about $52 million dollars. Surprisingly cheap for that much electrical capacity, though the usage factor would be pretty low, what with it being dark at night and all.
"producing transparent solar panels."
"As an external glaze, PV-TV allows up to 10% visible light to be transmitted through the panel."
transparent Audio pronunciation of "transparent" ( P ) Pronunciation Key (trns-pârnt, -pr-)
adj.
1. Capable of transmitting light so that objects or images can be seen as if there were no intervening material. See Synonyms at clear.
Gee, imagine what they could do with OPAQUE ones!
"...Well, there's egg and bacon; egg sausage and bacon; egg and spam; egg bacon and spam; egg bacon sausage and spam..."
Still much better than regular glass that doesn't produce any power.
Linux, you magnificent bastard, I read the fucking manual!
Bright sunlight, regardless of angle?
Diffused light on a cloudy day?
In outer space, facing the sun?
They say absolutely nothing about the preconditions that are necessary to produce that 3.8 watts... and it's simply not possible for it to produce the same output regardless of its environment.
File under 'M' for 'Manic ranting'
For comparison purposes a typical power plant will produce on the order of 1000 Megawatts (some are more, some are less but that's a good ballpark). Such a solar panel clad building would produce a fair amount of electricity for a solar application, but it's still a miniscule amount compared to the power demands of even a small city.
Has anybody considered that most skyscrapers are surrounded by -other- skyscrapers? Kind of cuts down on the whole direct sunlight thing......
I don't know where you got that idea.
White LEDs are less efficient than fluorescent lights.
Colored LEDs are quite efficient.
That's only if you used it one day and then threw it away. You need to divide by the number of days in use; if it lasted 10 years, that would come out to $1500/3650 = $.27/kwh. Of course, power inverters and storage would probably significantly increase the total cost above that.
"Is $19 million worth of glass really what you would want to get?"
Depends, you have to ask more questions:
1.) How much does the ordinary glass cost?
2.) How much electricity is generated? How much would this reduce the yearly bill?
3.) How much would/could electric prices rise?
4.) How long do these panels last?
5.) What other benefits are you buying? (I.e. is there resistance to power failures? Those in Cali during the rolling blackouts would appreciate that....)
6.) How does this compare to the cost of the rest of the building?
7.) Is running on solar power going to be attractive to tenants?
"Derp de derp."
$19 million, plus the cost of the mountings, and whatever system they use to wire together the glass and harvest the electricity.
On an unrelated note, the Aon Center (formerly the Amoco/Standard Oil Bldg) in Chicago was originally clad in white marble. Years later, the climate softened the marble and bits of it began to fall off. So they re-clad the entire building with granite in the '90s, which ended up costing them more than the original price of the building. At least the electricity-producing glass could alleviate the utility costs of the building, but who knows how long it would take until the glass ended up paying for itself.
However, if it turned out that the glass turned out to be inferior to normal glass (visibility, thermal properties, etc), then the owners would have to go through the costly process of replacing it with regular glass.
In many latitudes the Sun never comes anywhere close to being overhead. I've been in Alaska 28 yrs and never seen the Sun, Moon, or any planets even close to overhead. The highest they ever get is about 60 degrees above the horizon or so.
The article states that the factory where the glass is made is also the largest user of the glass:
The factory is now the world's largest single PV module plant, producing 100 megawatts of energy annually.
A megawatt isn't a unit of energy, it's a rate of transfer. Do they mean that it produces a continuous flow of 100 megawatts? If so, they would have to have 604 acres of glass (2.4 million of their 1m^2 panels). Of course you need to double that number because they're only collecting power half the day (generously assuming they're at peak output during all daylight hours)
On the other hand, if they're talking about generating 100 megawatt hours over the course of a year, then the plant is generating about 11,000 watts, or enough for about 10 average homes. By those numbers they'd have about 600 panels. That's a lot more reasonable.
Kevin Fox
Are you saying that ALL computers, including the Linux boxes will be powered by Windows.
Arrrrgggghhhhhhh
it is only after a long journey that you know the strength of the horse.
I think the question most businesses ask is how long will it take to get a return on investment.
The manufacturer specifies 38 W/m^2 or about 3.5 W/ft^2. Used as a window, the orientation would be fixed and I think you would be lucky to get four hours of good light to get something close to full efficiency.
So 3.5*4 = 14 Wh per day.
If electricity is 15 cents/kWh, you could buy 300 kWh for $45 (the cost per square foot of window).
To produce 300 kWh from a square foot of window would take 300 000/14 = 21 428 days or roughly 59 years.
Of course that doesn't take into account connecting your windows into the buildings power and the loss of effieciency there. And I also didn't take into account what the cost of regular windows are to begin with, since that should be reduced from the price, but I would guess they would be a few dollars and might take 10 years off the total.
Once electricy prices increase to $1.50/kWh these babies should be selling like hotcakes.
purves
Don't forget that the sun won't hit all 4 sides of the bulding. With the angle of incomming light, and the position of the sun during the day/season, you'd be lucky to get even a third of your calculated total electricity produced.
My Kyocera KC120 panels produce 12 watts per square foot, 3.8 doesn't sound above average to me.
3.8 Watts per square foot is a joke. Your average silicon panel (~10% conversion efficiency) is 4 times more efficient. Triple junction panels are 3 times better than that.
http://jsl.com/solar
Polycrystalline cells don't have this problem, and I can buy top shelf "BP Solar" branded cells with a 20 year warranty! Similar $/Watt too. What does this mean for the MSK-clad building? Will its enviro-friendliness fade? And what effect does age have on its transparency/opacity?
This two page .pdf provides additional and larger images. You can clearly see the etching and degree of tint. It also includes tables of electrical and mechanical specs.
If we knew what we were doing, it wouldn't be called research, would it? ~ Albert Einstein
Seems to me the most useful application would be in car glass for gas/electric hybrids. The power generated by the clear solar panels would go into the cars electric propulsion system when it is running and trickle-charge the batteries when sitting out in the parking lot.
Hey, who knows. Maybe one day drivers trying to park in parking decks will fight over top-level spaces to get their batteries charged.
theDunedan
At first, I read it as 3.8kW and said, "Hunh? That's more than the Solar Constant, 1.367kW per square meter." Then I reread it and saw that it was simply 3.8W. This sounded much more reasonable... and small.
This means that a 60W light bulb would need almost 16 square feet to function. Well, that of course is a reason to move to compact flourescents or LED light bulbs. But my computer takes up a bit of power. So does a refridgerator. So does a washer/dryer.
Let's say that it is a television. What's the equivalent of a square foot display (asuming a 5:4 ratio)? About 13"? Can a 13" LCD display work with 3.8W of power? (I don't know. That's why I'm asking.)
I'm not questioning whether it can give power. I'm questioning whether it can give sufficient power to offset the price. Or would the money be better spent elsewhere in green technologies to reduce the actual draw from the grid?
- I don't need to go outside, my CRT tan'll do me just fine.
$45 per square foot according to the linked page. That's less than $12 per peak watt. It's easy to spend more than that for conventional solar panels, though reasonably careful shopping will get you to the $6-7/watt range and Froogle showed one for $4.70/watt.
Do all four sides of the sears tower get direct sunlight? How many hours of full sunlight? The generating numbers for photovoltaic panels are always full sunlight output. Notice in the article how only the top and one side (the south side in the nothern hemisphere) is clad. Aiming photovoltaics east or west or north is not cost effective.
So you can build 13 similarly powered coal powerplants for the cost of one solar panel mounted to the Sears Tower
It might take $900k/megawatt to build a coal fired power plant, but once built you still have to sustain it. Its costs will continue for the life of the power plant. Once you put solar panels onto a building, aside from a little light maintenance (har har) it's a one-time cost.
Aside from economical benefits, it's also more accessible and conveniant to be hooked up to power from your own building -- there nothing much short of a true disaster that would knock out your power. Being off the grid can be a very good thing.
And of course, factor in the environmental impact. How much coal do we really have left in the world? It takes nearly 100 tons of prehistoric plant matter to create a single gallon of gasoline. I don't know how much prehistoric life goes into coal, but how about let's just not waste it in the first place?
Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
speaking of things passing overhead, that sound you just heard, a sort of cross between a whistle and a rush of wind, was the sound of a joke passing you by. as a slashdot coward, doubtless you were unfamiliar with the subject matter...
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I've seen strange math here today. Let's do the numbers.
First, these cannot be used as windows on cars. The minimum tint is something like 20%, and these allow only 10% of the light.
Second, at most two sides of a building receive sunlight at a time. In fact, it's the average of the cosine of the angle of incidence that matters.
Third, less energy gets through the atmosphere when the sun is near the horizon -- much less.
What we really want is the average of the product of the cosine with the transparency of of the atmosphere, which is equivalent to around 3 hours of straight on sunlight per day per 3 panels (none on the north face).
At 3.8 watts/sq-ft, it's about 3.8 watt-hours per day, per sq ft.
Electricity costs $0.08 per kilowatt-hour, so 1 sq ft of panel produces about 0.3 milli-dollars of electricy per day.
Because of clouds, there are around 150 clear-sky equivalent days/year, so that's about 5 cents per year.
Assuming a measly 3.3% interest rate, that income stream is worth $1.50 if that sq. ft. of panel lasts forever, or about 75 cents if it lasts an average of 20 years.
And the panel costs $45 per sq ft.
This is offset by the cost of glass which it replaces, which is neglible.
Most of the costs of production are energy, in one way or another (which is the point that most environmentalist REFUSE to admit). Even including a carbon-dioxide tax, these have to be much cheaper before they can be considered environmentally-friendly.
Why don't we just install a "Spaceballs" style solar glass enclosure around the earth at 26000 miles from the center? Just high enough to keep the geostationary satellites inside (wouldn't want to lose our tv). The surface area should be about.
t ml#IntlConsumption m l . html (seems accurate)
131,657,416,704,000,000 sq/ft
and cost
$5,924,583,751,680,000,000
in raw materials (maybe we could get a bulk discount)
we should also try to cash in on a "free installation"
The output of such a sphere would be
500,298,183,475,200,000 watts continuous
Or (for sake of easier calculation in an already complicated process) if only half of the sphere received light at any given time
250,149,091,737,600,000 watts continuous
250,149,091,737.6 kW continuous
250.15 Petawatt continuous
Power demand in 2002 for the entire world
13,747,393,531.8 kW continuous
0.0137474 Petawatt continuous
sure every living thing on earth would probably die and we would enter a perpetual ice age from the lack of light and heat but, you could throw away the sunscreen and with all that extra energy maybe we could string up some halogens or something along the inside! We could also sell advertising space on it.
All conversions made with http://www.onlineconversion.com/
Power consumption data from http://www.eia.doe.gov/emeu/international/total.h
Geostationary orbit data from how http://octopus.gma.org/surfing/imaging/howhigh.ht
Radius of the earth from http://www.page.sannet.ne.jp/ikenoue/e-mode/earth
Output and cost from RFTA
If you think that my math is wrong then check and let me know, too tired to think anymore.
Just to note, an average coal plant releases 88 pounds of uranium into the air a day. So, nuclear is much cleaner than coal. :-)
Hurricane Ivan: A 17th century prison collapsed. All of the inmates escaped.
Not that I'm a consipracy theorist or anything, but of course it does. That is the US Department of Agriculture after all. And we're talking about what? Corn ethanol? Hmm, corn is an agricultural crop.
Now, take a look at the first two bullet items from their mission statement:
Do you honestly think they'd ruin a perfectly good opportunity for one of the largest food crops in the US by speaking badly of corn derived ethanol? Please...
... industries for NOT using power reclemation and "free source" power generation (wind, solar, brake regenerative)
I wonder if there will be any cities that will ever require buildings to have such technologies in the new construction, just as say Germantown Tenneesee requires no backlit signs above a certain height and at that can't diplay food items. They also have restrictions about trees and shrubs having to be every few feet in a parking lot and cobble stone or brick pavers instead of concrete or black tar paving.
Reclamation and regeration could EASILY revoltionalize the tax system in my opinion. One of the number one costs to most cities is paying for the power for stoplights, government buildings, and sign illumination. If this cost were significantly reduced or eliminated, it could be extra money in the taxpayers hands and therefore less tax increases or maybe even a rollback.
Yell & scream & rant & rave... it's no use... you need a shaaaave ~ Bugs Bunny
I was just reading that Kanazawa Station in Japan will be built using this as an exterior skin. I used to teach English in the Hokurikku region (of which Kanazawa is a part of) and one of my students was an ederly man that sold home solar power units. In this area of Japan I saw quite a bit of solar powered home units. On train rides through the area it's very easy to spot the roof top systems. With electricty in Japan running as high as it does it's easy to see the attraction to solar power. And with a whole building covered in this stuff... you can bet the station will be selling excess power to the power company at peak hours.
http://yarchive.net/nuke/coal_radiation.html
The best one: http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html
Hurricane Ivan: A 17th century prison collapsed. All of the inmates escaped.
So for $45 * 95 square feet, you can run the VOS Pad LEDs. Of course, I acknowledge that you pointed out that this is when all lights are on full. What you failed to mention was that the VOS Pad costs £35,000 (about US$52,500). This is not practical. The return on investment would likely take the better part of your life -- if even that short. Sure, it could take this portion of your energy consumption off the grid, but how much energy was required to make these materials in the first place? How much energy was used by the manufacturing facilities? At a price of £35,000, you can bet it isn't peanuts.
As for OLEDs, yes they look promising. However, until they actually hit mass market, we don't know actual numbers. Looking at this press release, Samsung's 17" display "will consume no more power than a 15-inch display..." Sure you can take away the backlight, but this is not the same as slashing the total power consumption. Reduces it, yes, but doesn't make revolutionary drops. On the bright side (no pun intended), OLEDs have the potential for cost savings.
You're right. We should attack it from both ends or at least leave everything open as possibilities. However I still believe that I was right. We should not concentrate on technologies that only provide marginal improvements for the amount of money/resources spent. We shouldn't ignore them of course, but we definitely shouldn't fixate upon them. We have a limited amount of resources and money. For better or for worse, this is the reality of our world: scarcity and commerce.
Who cares if my electricity bill is reduced by half or even eliminated entirely if the initial cost in materials exceeds what I would pay in electricity for the next fifty years?
If a solution presents itself that uses more resources or costs substantially more than our current methods, it is not a good solution. In some circumstances I could see this PV glass making sense. In most scenarios though, I see it as a curious novelty that makes little sense for the average Joe like myself.
As I look out one of the windows in my bedroom, I estimate that the 2.5 by 3 foot window would cost me around $337.50 to replace just the glass. (I'm sure the framing would add to the cost.) I have three such windows in my bedroom. For some odd reason, I think my money would be better spent on double-paned replacements and using the money saved on both initial investment and heating costs to pay for my energy bills until the technology improves in a few years.
At $45/sq. ft., the $1,012.50 (at least) I would spend on three PV glass windows would not be recouped anytime soon. I like to think of myself as an optimist, but I'm not that blindly optimistic. Assuming 22.5 sq. ft. of PV glass, 3.8W/sq. ft., 7hrs of useable sunlight a day for 22 sunlit days a month (on average), I get a little more than 13kWh (kilowatt hours) per month. Let's say I pay about 10 cents per kilowatt hour -- pretty expensive I think. This means I get back $1.32 every month from these windows. Woohoo! I will have paid for them in 64 years! Well... That's assuming they last for 64 years.
- I don't need to go outside, my CRT tan'll do me just fine.
This is revolutionary because it nows allows solar panel installation in a place where no one could before: on windows. I don't understand all the bitching about the panel's inefficiency. The panel is a compromise, if anyone read their website, they etch lines into it with a laser.
...During the manufacturing process a laser scribes a series of ultra fine lines, allowing 10% of visible light to be transmitted through the panel...
Of course the efficiency goes down when you remove 10% of the photovoltaic material, but if you can put it up where windows used to be, you end up winning in the end. This is especially true for office towers and skyscrapers which mostly have exclusively glass exteriors. This technology will not replace existing panels. Current opaque solar technology will always have it's place on roofs and walls. The invention of clear solar panels allows those opaque panels to be complemented by making more surface area available to install panels on existing glazing surfaces.
Divide by zero hurts my brain.
To increase the amount of electricty generated, graned the inner layer would not generrate as much electricity, but could they manufacure a mutiple layer semi-transparent window pane? Maybe use the mutiple layers to increase effecincy per square ft.???
Tsukasa: All I really want, is to be left alone...
Architects and engineers are looking into ways to make building more efficient. (Sometimes the clients request it, sometimes they sell it to them based on calculations of cost over the life of the building)
William McDonough: he is a leader in the field and has been influencing other high profile architects to include exactly those kinds of features into new construction. Along with passive heating and cooling and natural lighting.
Some recent projects that do not fit the stereotype of sustainable or green building include 4 Times Square (skyscaper) by Fox and Fowle and the David L Lawrence Convention Center by Rafael Vinoly.
"I'm an indescribable shade of twilight...Any second now I going to turn myself off"