Slashdot Mirror
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."
"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.
Still much better than regular glass that doesn't produce any power.
Linux, you magnificent bastard, I read the fucking manual!
" Wait, how much do the super-efficient panels cost? Oops..."
A.) Prices will go down if these things take off.
B.) Think of how much cheaper the electric bill will be. (Also consider how much more regular it has the potential to be.)
C.) Imagine if an ill-timed power outage wouldn't necessarily mean the building was affected.
I imagine once somebody sits down with a calculator and thinks out 5 to 10 years, the cost will end up being quite competitive AND they get bonus features to boot.
Just because something starts out at a high price doesn't always mean the value's not there, or that the price will always stay that way. The main reason I'm replying is not so much because of your particular comment, but because I've seen a great deal of sticker-shock on Slashdot without understanding some of these basic things about how technology economics works.
"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.
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
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.
I gotta look at my 165 W sharps which are about 8sq feet and wonder at that. But my panels are not clear. Which is a plus as the also shade the roof and make that part of the house cooler. (if only they had 1/2" pipes wired under them so I could water cool them and run the warmed water into a tank).
And yes, the windows are mounted vertically. In math, that's at 90 degrees.
The ideal mounting angle is your latitude (eg the Bay Area and DC are around 37 degrees).
So these will be most efficient at Sunrise/Sunset. When the sun is at its weakest (lots of atmosphere to get through).
On the other hand, if they are good projection screens, you aim your projector at it, that causes it to generate power which you can use to plug the projector into!! Perpetual energy!!!
or something.
Bottom line:
If they work and don't cost a lot more than regular windows (such that in 10 years they save more in power costs than they cost), then great!
If every house with a decent roof exposure between 10 and 3 has even 4 solar panels on and generated even 20% of their own power, and there was enough to knock 5% of power use down in our country (world?), then it's a win.
There's no need to "go off grid" and raise your own goats for food and knit you're own underwear to use solar.
(Now, if you switch from CRT to LCD, you save having to buy $500 of solar panels...)
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.