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Record-Breaking Solar Cells Tailored To Location
Urchin writes "The quality of sunlight varies depending on where you live, but off-the-shelf solar cells are all identical. A new solar cell designed by UK firm Quantasol is easily tuned to adapt to the local light conditions, which boosts its long-term performance. Its short-term performance isn't bad though — the single junction solar cell has a peak efficiency greater than any previous device, beating a world record that's stood for 21 years."
Wake me up when I can plug an extension cord from a tree to my data center.
I know I'm heading to the moderation cellar for this, but COME ON guys, don't be so damn lazy about your language. See my sig below.
That kind of mistake is a huge cognitive speed bump for many readers. You're blowing your chance to communicate with your audience when you make (and belittle complaints about) adolescent mistakes like this.
One simple rule for its versus it's
Multi-junction cells are over 40%.
We should start dealing in those black-market beagles.
I know I'm heading to the moderation cellar for this, but COME ON guys, don't be so damn lazy about your language. See my sig below.
That kind of mistake is a huge cognitive speed bump for many readers. You're blowing your chance to communicate with your audience when you make (and belittle complaints about) adolescent mistakes like this.
Efficiency doesn't really matter. What we really want is the lowest cost per kWh. What's the price of these?
"The commercial market doesn't just want high efficiency, they want the device to be optimised to the environment," he says. "In the past we measured performance in dollars per watt. Now it's cents per kilowatt-hour that's more important."
This actually sounds like they're on the right track, but until I see prices I'm not convinced the process is a cost-saver. Also it sounds like it's only useful in concentrating designs.
"I assumed blithely that there were no elves out there in the darkness"
If it's expensive nobody will buy it. Regardless of how well it works. For example, if the prius cost $80k the environmentalists wouldn't even buy it. I think that these enviro-tech things just have a zero shot at catching on if they are too damn expensive. Just a thought.
They're quite environmentally sound. They're made of arsenic, and many caustic chemicals being used to refine and produce them. In short -- not suitable for mass alternative energy (like just about every other thing called "green").
Reality: Solar power's only economical use right now is for remote sensors and in locations where the power grid cannot reasonably be extended and delivering fuel is impractical.
#fuckbeta #iamslashdot #dicemustdie
30%? 40%? Efficiency only matters if you're constrained by space (airplanes) or by weight (satellites). 15%-efficient solar cells are good enough that you can power your house with them by covering your roof -- or would be, if they were produced cheaply and in quantity.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
Not to belittle this accomplishment, but I'd prefer to see an increase in average efficiency. According to the article the peak efficiency is found when panels are exposed to light 500 times that of normal light. How does that translate to efficiency under normal operating conditions (such as a semi-cloudy day in the midwest)? The article is rather short on details concerning how well the solar cells operate when they are "tailored to their locations."
God, schmod. I want my monkey man!
Current silicon cells are about 15-20% average efficiency, NOT 10-12%. They peak at just over 25% efficient as demonstrated by the research lab at the University of New South Wales in Australia.
SunPower A300 silicon cells average about 20% per bin.
How would it adapt to the darkness of my soul?
A Magic the Gathering Article and Forum Aggregator
It's true. The Fraunhofer Institute itself has produced more efficient cells. And all use multiple junctions.
Examples:
Fraunhofer - triple junction
NREL - triple junction
University of Delaware - bream splitting
All claim to be the record because there is no standardized way to measure power efficiency. However, the concept of quantum wells used in solar cells is a new concept.
I have left slashdot and am now on Soylent News. FUCK YOU DICE.
Right, and since this thing is already made of GaAs, why not go all out and use a triple-junction cell? Their goal is to tune it to a specific wavelength, but triple-junction cells are already absorbing more wavelengths.
My guess is that it's a lot more expensive. Semiconductor devices have to be processed in vacuum conditions and often at high temperatures; and the more precessing you use (triple junction has minimum 4 layers), the higher the cost. This is why there's interest in alternative, non-semiconductor devices like dye-based and conjugated polymer cells. Easy to produce in solution and at low temperature, no vacuum. There's a plethora of other undesirables in semiconductor solar cells too, like weight, inflexibility, etc.
I have left slashdot and am now on Soylent News. FUCK YOU DICE.
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Comment removed based on user account deletion
It sounds like the interesting part here isn't the efficiency but that it's efficient enough and can handle a lot of extra sunlight via mirrors. The article fails to give any info though on what kind of efficiency other solar cells can achieve with mirrors focused on them. Without any reference it's hard to get an idea for whether or not this is even useful though.
multijunction cells can also perform worse then single junction cells in non-optimum light conditions. A cell's output is effectively throttled by the lowest producing junction (similar to why it's so bad to allow a shadow to fall on part of an array). So if its cloudy or something and most of your light is reflected, you can get more power out of a low-wavelength single junction cell then you can out of a triple junction one.
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And no doubt these new improved cells will be available for commercial use in only 5 years - for the next 25 years!
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Eh, beat me to it! And there have been incremental increases in efficiency across a whole range of cell technologies on a regular basis, including the use of quantum wells, (and other quantum effects), in other materials. In fact, the only reason it's even possible to insinuate any big hoopla about GaAs cells is that they've been around so long a lot of experimenters have stopped trying to improve them. Badly worded article/summary for sure...
It does not matter at all when solar cells take more energy to make than they will generate through their entire lives. Which was at least true for solar cells a decade ago. Maybe even today.
What is the ratio (energy produced):(enery to make)?
I'm not trying to berate the accomplishment or the effort, but 28.3% efficiency vs. 10 - 12% and light 500x brighter than sunlight? Where on Earth will that occur? Also, Mr. Arthur states that the new cells can "generate." Solar cells generate nothing. They convert one form of energy into another. As a matter-of-fact, you can neither create nor destroy energy, you can only convert its form. I'm sick of folks talking about "generating" energy. I have occasion to build solar-powered repeaters for relay from remote locations. My first complaint is the size, second is efficiency. The solar cells are about 3'Hx1.5'W and have an output of around 19VDC for a 12VDC photocell. What do I do with the extra 7VDC? It's wasted as heat. I have to use a charge controller to regulate the voltage down to a useable amount. This increases my cost and decreases the over-all efficiency of the site. How much to you really need to convert when you cannot use but a certain amount?
It won't power your data centre, but then again your requirement didn't make any sense anyway.
Isn't the difference that you cannot use the entire surface area as solar converters and that the dead areas mean you're wasting ~2/3 of the surface to routing energy to the output?
I must be missing something, because they used "its" correctly in the original post. "its" is for possessive because "it's" is reserved for the contraction of "it is". "Its" is more similar to "his" or "hers" than "gadget's" or "cell's". but since you've been modded informative instead of funny, I'm guessing my understanding has been eclipsed by the greater /. audience's wisdom. Perhaps someone would condescend to tell me what I'm missing? Perhaps the original post has been edited since this comment was made? Knowing my luck I'll get modded 5 funny for my quaint naivete....
Cut-n-paste:
Factoring in all these issues, various groups have attempted to calculate a true economic cost for electricity generated by the most modern designs proposed. Because if an actual cost per kW*h can be calculated, then it is possible to compare it to other power sources to determine if such an investment is economically sound.
In 2003, the Massachusetts Institute of Technology (MIT) issued a report entitled, "The Future of Nuclear Power". They estimated that new nuclear power in the US would cost 6.7 cents per kW*h.[1] However, the Energy Policy Act of 2005 includes a tax credit that should reduce that cost slightly.
The lifetime cost of new generating capacity in the United States was estimated in 2006 by the U.S. government (the 2007 report did not estimate costs). Nuclear power was estimated at 5.93 cents per kW*h. However, the "total overnight cost" for new nuclear was assumed to be $1,984 per kWe - as seen above in Capital Costs, this figure is subject to debate.
A 2008 study based on historical outcomes in the U.S. said costs for nuclear power can be expected to run $0.25-.30 per kW*h.
A 2008 study concluded that if carbon capture and storage was required then nuclear power would be the cheapest source of electricity even at $4,038/kW in overnight capital cost.
In 2009, MIT updated its 2003 study, concluding that inflation and rising construction costs had increased the overnight cost of nuclear power plants to about $4,000/kWe, and thus increased the power cost to 8.4c/kW*h.
http://en.wikipedia.org/wiki/Economics_of_new_nuclear_power_plants#Cost_per_kW.C2.B7h
Well, if you use a 4 sq. foot lens over a 1 sq. inch cell you have ~576x brightness, assuming a perfect lens and no atmospheric absorption. More realistically you'd get closer to 500x brightness.
So if you use cheap, non-imaging fresnel lenses as concentrators you can get by with far fewer cells. At 28.3% efficiency, that 1 sq.in. cell will put out up to 0.2Kw, depending on location.
You can argue that they are converters rather than generators but that's just being pedantic.
I've been on slashdot so long I'm starting to get out of touch with the cool stuff if it ain't on slashdot.
For some reason, snow and solar panels get along like a big house on fire.
What I heard is that there are small scale, ie residential, solar installations here in MN. Heck even solar thermal water heating is being used. MN is also good for wind. Though not much the state produces megawatts of energy from wind.
Falcon
Should there be a Law?
I am happy people can design solar cells that convert light to electricity at higher efficiencies.
But for me, I am interested that the price per watt of power goes down. So I would hope some folks are focusing price efficiencies. When I read solarbuzz, the price has basically been stuck around US$4/watt for years.
Uh, Linux geek since 1999.
I am getting bored with all these technological breakthroughs that mysteriously never seem to actually lead to something I can pay money for and get in my hands. Plastic optical memory, I am looking at you, too.
Yes but this cell isn't meant for production it's a proof of concept which would go into a mulitjunction cell to hopefully get the efficiency over 40%. The big hurdle for MJ cells at the moment is finding a 4th 1eV bandgap cell. Perhaps this could provide it. It's other advantage is that efficiency is a poor metric for meauring performance. What's really important is kwh/year. These cells can be tuned to the spectral conditions of a specific place: Southern Spain/California/the Middle East have similar quantities of solar energy but are spectrally different.