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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.
Most glass is mounted vertically so it will only be good in the mornings/afternoons.....
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
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."
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.
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
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.
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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.
Moving to LEDs will cut prices drastically. The VOS Pad is lit only by ultra-bright LEDs, around 400 LEDs grouped into 135 fittings that can show 16.7M colours, and only consumes 360W when every light is fully on. Computers are way over-powered for 90% of users and people could benefit by buying a less power-hungry machine (even a laptop, as their prices have dropped drastically).
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.)
New OLED technology should cut the power even of the LED display considerably as it no longer needs a back-light.
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?
Wrong answer. The best thing is to attack it from both ends, the suppy and the demand. I don't understand some of the "it won't supply 100% of my needs" negativity by some people (not yourself). If someone came and showed me how I could lower my electricity bills by eg 50% then I'd be interested.
Phillip.
Property for sale in Nice, France
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.