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New Solar Cell Sets World Efficiency Record
asoduk writes to tell us that a new world record has been set for the most efficient photovoltaic device. Topping the scale at 40.8% efficiency, the new solar cell differs significantly from the previous record holder. "Instead of using a germanium wafer as the bottom junction of the device, the new design uses compositions of gallium indium phosphide and gallium indium arsenide to split the solar spectrum into three equal parts that are absorbed by each of the cell's three junctions for higher potential efficiencies. This is accomplished by growing the solar cell on a gallium arsenide wafer, flipping it over, then removing the wafer. The resulting device is extremely thin and light and represents a new class of solar cells with advantages in performance, design, operation and cost."
Call me in 20 years when they're in production. Seems it always takes that long for these innovations to get to market nowadays.
cool? yes, but only in the most esoteric sense. I've said MANY times before, fantastic new photovoltaic technology is announced every 6 months or so, NONE of it ever reaches the market. Call me when the ROI on home solar breaks the 20 year mark in my area. Right now it's almost 100 years.
At 40%, you're talking about 400W when in direct sunlight. With eight hours of sunlight per day the average house needs less than four square metres. Now, of course, you aren't going to be using the most power at the times when these are generating, but it can definitely put a significant dent in your electricity bills.
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Even TFA doesn't say what the previous record was or provide any quantitative comparison.
Was taking forever to load, so here's the article:
Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have set a world record in solar cell efficiency with a photovoltaic device that converts 40.8 percent of the light that hits it into electricity. This is the highest confirmed efficiency of any photovoltaic device to date.
The inverted metamorphic triple-junction solar cell was designed, fabricated and independently measured at NREL. The 40.8 percent efficiency was measured under concentrated light of 326 suns. One sun is about the amount of light that typically hits Earth on a sunny day. The new cell is a natural candidate for the space satellite market and for terrestrial concentrated photovoltaic arrays, which use lenses or mirrors to focus sunlight onto the solar cells.
The new solar cell differs significantly from the previous record holder - also based on a NREL design. Instead of using a germanium wafer as the bottom junction of the device, the new design uses compositions of gallium indium phosphide and gallium indium arsenide to split the solar spectrum into three equal parts that are absorbed by each of the cell's three junctions for higher potential efficiencies. This is accomplished by growing the solar cell on a gallium arsenide wafer, flipping it over, then removing the wafer. The resulting device is extremely thin and light and represents a new class of solar cells with advantages in performance, design, operation and cost.
NREL's Mark Wanlass invented the original inverted cell, which recently won a R&D 100 award. His design was modified by a team led by John Geisz that further optimized the junction energies by making the middle junction metamorphic as well as the bottom junction. Metamorphic junctions are lattice mismatched - their atoms don't line up. The material properties of the mismatched semiconductors allows for greater potential conversion of sunlight.
NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by Midwest Research Institute and Battelle.
http://www.treehugger.com/files/2006/12/new_world_recor.php
TFA is slashdotted, but a little googling shows this happened two years ago.
How can I believe you when you tell me what I don't want to hear?
We will have solar energy as soon as the utility companies solve one technical problem -- how to run a sunbeam through a meter.
They say a little knowledge is a dangerous thing, but it's not one half so bad as a lot of ignorance. - Terry Pratchett
Just guessing here... 3-5 years.
I no longer get excited about stories like this, as it doesn't matter unless someone figures out how to mass produce this stuff and make it available for the market. If I'm not mistaken photovoltaic production hasn't changed in years despite all this new technology. Why not run a story on why mfgs are taking so long to adopt this.
Unless you grind them up and snort them you're probably safe.
There is more than one company who claims to be on the way to $1/Watt.
But right now, subsidies in Germany are so high that PV vendors can sell for more than $1/Watt, and find customers. So you will get $1/Watt on the end user market when the German market is saturated, which will probably take a few more years.
On the upside, we Germans essentially pay for the development of all those nice improved PV cells, because our subsidies guarantee a market ;-)
C - the footgun of programming languages
Alternatively, you can use a Fresnel lens instead of a mirror.
That doesn't seem to matter to the health nuts. If there is even the slightest remote possibility it theoretically could cause cancer even only in the most unlikely of conditions they will do everything they can to make sure that this cell never happens.
"I would love to see for just once, an article that states that the mentioned technology is being produced en masse and possibly a website from where I can order it, wherever I may be at a reasonable price. I am asking too much, eh?"
So you want an advertisment?
To do something right, you often have to roll up your sleeves and get busy.
Indium is a very rare material, one which we're slated to deplete in less than 10 years or so at current rates of consumption, due in part to its use in display screens.
I highly doubt that widespread use in solar cells would be feasible.
Nice efficiency, though.
Kythe
I'm just curious-- not implying that your calculations are wrong. I'm at the extreme other end in Arizona, and payback appears to be in the 10-15 year range for us, not counting resale and using a constant price for power for the next 15 years. That's well within the system warranty time, but may still be a bit too much for people to pay for up front.
Payback speed depends heavily on your local utility, their rates, their incentives, and whether they allow net-metering over the entire year, or just monthly. It also depends on whether or not you are willing to consider resale value as part of your payback time.
I suspect Hawaii is even better than Arizona despite having more cloudy days, just because power is so freaking expensive there.
In the long run, I think leases will win out. A couple of companies are offering deals where you lease the system and panels, and they promise your new smaller electric bill plus the lease cost will be lower than your current electric bill. A deal like this makes things suddenly interesting to people who don't have $20k to drop up front.
These things will be *very* expensive, I'll guess that the main application will be in spacecraft solar panels.
First, they use gallium, which is an expensive material. Second, from the description in the summary (TFA is slashdotted), they do one side, then flip it over and etch the backside to get at the junction from the back. Seems like a costly manufacturing process.
Hmmm.. I wonder if the solar energy crowd would be into recycling?...
How much do they cost and when can I get some?
If the goal here is to move away fom the consumption of materials in short supply, solar cells based on gallium and indium aren't going to help. We had a world-wide gallium shortage at the turn of the millenium, and that only receeded because demand slacked off some. There is currently a shortage of indium that started in 2007.
Both of these elements are hard to come by because they are not just rare, but sparsely distributed. Indium is produced from lead, zinc, and tin production waste, and I think gallium mostly from aluminum production waste. I'm sure supply will increase over time, but we can't quickly ramp up production of either element by "mining more".
Niether of these elements would remain economical if there were a sharp spike in demand.
Socialism: a lie told by totalitarians and believed by fools.
Price gouging: Not enough of it.
Can you be Even More Awesome?!
Unless you grind them up and snort them you're probably safe.
Oh crap... You mean you're not supposed to do that!?!?
I better call my doctor.
Well, back to rejecting software patent applications.
Why does everyone think these would be used to produce electric power for domestic use? Something like this is much better suited for use on spacecraft.
When you are covering your roof you care about the power/cost ratio. On spacecraft you care a lot about power/weight ratio. This new type of cell address power/area which translates directly to power/weight
Too bad there isn't a "-1 Incoherent" mod.
Does this need to be said again? There's no shortage of roof space and other places to locate solar cells, so the efficiency of the cells is only a marginal issue; the bigger issue is COST. Instead of focusing all the research on this penile my-cell-is-more-efficient-than-YOURS pissing contest, it ought to be focused on finding least toxic and least expensive means of production. Certainly large scale mass production will eventually reduce costs, but large scale adoption won't occur until they can be produced inexpensively enough in the first place to motivate widespread use. Efforts should be focused on finding the least expensive and least toxic method of production for now, and worry about improving efficiency once their use has become commonplace.
WTPOYSAIYHTWIANTITEIA? (What's the point of your stupid acronym if you have to write it all next to it to explain it anyways?)
source
I actually think there is a simple source to this. It's not so much to store energy but to re-direct it. If home owners with solar arrays are hooked up to the electrical grid they can sell power to the grid during the day to supply business and manufacturing. Then at night the grid will forward excess power not used by business back to the homeowners. There is no need to 'store' energy in the traditional sense.
I don't see the problem. All we need to do is develop a cheap, efficient form of fusion to create the exotic elements we need so that we can produce these solar cells to provide a new source of cheap, efficient energy.
Maybe it's time we start mining the landfills.
Please choose a doctor:
A. Doctor McCoy, who's going to make you take some magical pills and ask you to get a good night sleep.
B. Doctor Crusher, who'll treat you and then send you to counselor Troy to deal with any emotional damage.
C. Doctor Bashir, who'll invent a whole new treatment because he can't be bothered by "ancient techniques" created by normal humans.
D. The Doctor, who'll simply laugh at you while mentioning something along the lines of "hologram can't be harmed by such trivial things".
E. Doctor Phlox, who probably has some kind of alien leeches he can put on you to drain out the toxins.
F. The Doctor. He's not a real doctor, but I guess he could send you back in time to warn yourself not to do that in the first place.
I will personally guarantee to you that they are not cancergnous.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Call me when the ROI on home solar breaks the 20 year mark in my area. Right now it's almost 100 years.
You don't get much sun where you're at do you? Here's a spread sheet you can play with to calculate ROI, now I haven't looked at it so I don't know how good it it. This is the webpage that links to it. Of course you'd get a better return by increasing energy efficiency.
Falcon
Should there be a Law?
Very valid point. The ROI is directly dependent on the expense it's replacing. California and Florida have the shortest ROI on home solar due to their combination of high electricity prices, large governmental subsidies, and sunlight density. If oil went up to $500 a barrel tomorrow, the ROI on solar becomes VERY interesting even in sunlight poor areas. As an interesting perspective, the proposed $700 billion bailout currently under consideration by the government would fund 100% of home solar power needs for 35 million US homes.
Why mess around with solar cells when you can use that technology to turn lead into gold. We'll have so much gold that everyone on this planet will be so rich that they won't have a need for cheap solar power.
House is not a name. What's next, Doctor Building, Doctor Roof and Doctor Door?
...and there's the proof that those chemicals in your blood are dangerous to your health. Any questions?
- Greg House.