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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!
Has anybody considered that most skyscrapers are surrounded by -other- skyscrapers? Kind of cuts down on the whole direct sunlight thing......
"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?
While it may be miniscule for a city, would a Sears Tower application, generating 4.2 Megawats, be able to power the building itself? I wonder what the average consumption of the Sears Tower is?
Of the Gigawatt produced by a power plant, how much of it is lost to power transmission? I mean, if these powerplant-esque high rises are closer to the point of consumption, aren't they a tad more efficient than the traditional at-a-distance power plants?
What those who want activist courts fear is rule by the people.
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.
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'
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.
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...
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...