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80% Improvement In Solar Cell Efficiency
An anonymous reader writes "Chemistry researchers at Oak Ridge National Laboratory say they've improved the efficiency of typical solar cells by a whopping 80% by creating a 3-D nanocone-based solar cell platform. The technology tackles the problem of poor transport of charges generated by solar photons. These charges — 'negative electrons and positive holes' — typically become trapped by defects in bulk materials and degrade performance. 'We designed the three-dimensional structure to provide an intrinsic electric field distribution that promotes efficient charge transport and high efficiency in converting energy from sunlight into electricity.' Bottom line, they say, is they've boosted the light-to-power conversion efficiency of photovoltaics by 80 percent."
20%? So it's 36% now?
2020?
Yours In Crawford,
Kilgore Trout
Call me when it's on the market.
With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency of conventional planar structure of the same materials.
So the efficiencies went from awful to slightly less awful.
To be pedantic, they have boosted the efficiency of LOUSY solar cells.
They've taken a 1.8% efficient solar cell and turned it into a 3.2% cell.
I wish the world's press offices would declare a moratorium on announcing breakthroughs in solar technology.
http://www.geoffreylandis.com
From the fine article: "With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency..."
So, with a ridiculously bad solar cell, they could increase the efficiency to something that's still ridiculously bad.
The key to solar cells is watts/dollar.
Thad
I love Mondays. On a Monday, anything is possible.
Wonderful! Amazing! ...Just like the other half-dozen or so solar cell improvements I've read about over the past few years.
But unless we can actually BUY these upgraded units soon, I'd like to add one more appropriate adjective: Pointless.
(Okay, maybe not entirely pointless. But that's what it feels like when all of these more-efficient panels never seem to show up anywhere.)
This year, I have had an, on average, 75% increase in shoe purchases. That is to say I bought a pair of shoes this year. So an 80% increase is what? Can we get some real numbers here. If this goes into production, how much do I need to power my home?
No single raindrop believes it is to blame for the flood.
Anyone told Exxon and the Saud's yet?
"If any question why we died, Tell them because our fathers lied."
From the fine article: "With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency..."
So, with a ridiculously bad solar cell, they could increase the efficiency to something that's still ridiculously bad.
Exactly. It was miserably inefficient previously, and now now its 180% of miserable.
If the same techniques could work on the top-end PRODUCTION solar cells, which hover around 20% you could perhaps approach 35%.
But the whole idea of % efficiency is fraught with peril. which is why people usually revert to dollars per watt per square meter or some such.
Sig Battery depleted. Reverting to safe mode.
Dollars per square meter (or perhaps kilowatt-hour) is the only really relevant measure. Once it's cheaper to make electricity this way it will take off.
I have mod points. The reign of terror begins now.
Efficiency is not irrelevant. A given installer only has a finite amount of space to make use of, installing panels costs money, running wires costs money, etc. And especially if they're on a heliostat, but even if they're not, you have to build them hardy enough to withstand the weather for decades. The per-panel or per-square-meter overhead is not irrelevant, and thus efficiency is not irrelevant.
"Lock and load, Brides of Christ!"
The question is what was the base efficiency they were starting from ?
If the efficiency was 10% before it is now 1.8 * 10 = 18%
If the efficiency was 15% before it is now 1.8 * 15 = 27%
If the efficiency was 30% before it is now 1.8 * 30 = 54%
If the efficiency was 60% before it is now 1.8 * 60 = 108% - > thats unpossible
The crappier it was to begin with the easier it was to make it better.
Where they actually are
"With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency of conventional planar structure of the same materials."
Wow 3.2% efficiency. Great stuff indeed.
But if you look around other people are doing more than 10x that or a 1600% increase over the base line for this report.
Crystalline silicon devices are now approaching the theoretical limiting efficiency of 29%.
http://en.wikipedia.org/wiki/Solar_cell_efficiency
Ahh. Solar powered lesbian sex robots, no taller than your little finger. What will they think of next?
"Flyin' in just a sweet place,
Never been known to fail..."
Maybe so, but the mainstream solar cell market is already at 18-24% efficiency. These clowns are only at 3.2%. If this one shows up on the market nobody will care even if they are dirt cheap and you can paint your house with them. The solar paint technology, as bad as it is, is already at 5% efficiency.
180% of Meh is still effectively Meh.
I use irony whenever I can, but my shirts are still wrinkled...
It is unfair to speak in such one dimensional terms. In many cases, there is a direct correlation to cost. Consider, for example, how a more efficient solar cell can reduce the mass (and by extension launch cost) of a satellite. Maybe a few of us have become jaded by the exponential growth in some sectors of high tech. In the real world, however, progress occurs in increments and every little bit is worth celebrating as a step closer to the next breakthrough.
Stay sentient. Don't drink bad milk.
efficiency doesn't matter to me at all. Price / watt does
I don't care if they are 100% efficient if they cost $20billion / watt.
But show me one that is cheap enough to afford to cover my roof with that the end total wattage is enough to cover something close to my power use (or more) and I'll do it.
The % efficiency make absolutely no difference to me at all, zip, zero, nada. DON"T CARE!
If this product can be reliable and cheaply produced it will rock the world. I feel that it will likely be buried away from public use or view for many decades.
Solar cells can now be purchased for about $3 a watt. That's WAY down from 15 years ago and greatly decreases the period until payback.
The problem with price per Watt, while that's certainly important, is that, say for example with current Tech, covering every square inch of your roof with solar panels gives you, let's say 1kW, that's the maximum you can get out of the area of your roof. You'd need more area to get more power.
Now, increase the efficiency by 80%, and you get 1.8kW out of that same area. Of course, if the price increases more than 80%, then you are coming out behind, because even though you get more power, it costs more.
The hope would be that you get 80% more power at something less than 50% higher cost.
you can buy 400W panels today. They are huge however.
You can reduce the size by 80% and get the same amount out of them.
In effect this puts it into the reach of people covering the tops of their houses with them. Cost wise not so much.
Look at it this way, you can use a smaller footprint to gain the same amount of power. That's savings you cant pass by if it gets commercialized and is cheaper than current models.
The problem with current Solar cells is not efficiency. Well, in a way it is of course, because every improvement helps along the economics.
The real problem is that the panels require a huge amount of energy to produce as they rely on highly refined materials. So much energy is required that it takes years or decades to break even.
Moar efficiency == less material required. Same mfg cost & less material == less cost / watt. You do care!
Sir, I get it that you must have a large roof...
Please. Please. Please read the article and try to understand it before posting breathless announcements like this one. From the article, "With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency of conventional planar structure of the same materials." This article announces a breakthrough in efficiency for this type of material. For reference, typical photovoltaic silicon cells run around 10-15% efficiency, and the world record is around 25% efficiency. Thus, the questions you should ask after reading this article are "so what," "why would I build a cell out of this material when conventional silicon beats the living crap out of it," "how do you plan to produce this on an industrial scale," "will this ever see the outside of your lab," and "you need some published articles in order to get promoted, don't you?"
...Reagan didn't act like a petulant fucking child in 1986 when he tore down the White House's solar panels, and instead opted to invest in infrastructure and lead by example?
Granted, that might've delayed the booming 25 years of trickle down wealth we've all enjoyed, but perhaps it would've been worth it?
I read about this in a New Scientist Magazine a looong time ago. They blasted silicon with a laser to produce small cones on the surface, which sounds exactly like the "3-D nanocone-based solar cell platform" described here.
Like someone else said, when it hits the market, then I'm interested about hearing about this.
According to the article, part of the cell is composed of cadmium telluride. Both are toxic and various compounds of tellurium stink to high heaven. I wonder what happens if the cells get caught in a fire?
The Saud's are running out oil anyhow. They need to start planning for how *they* will power their nation when the oil production drops to 50% of what it used to be.
There's a reason that the UAE is planning a $20Bn nuclear plant. Saudi Arabia is part of a coalition of States working with UAE on that plant, and I believe the idea is that they'll build a large plant in UAE, then Saudi Arabia and other nearby nations can buy power from that plant, sent via transmission lines.
However, while solar isn't a great option in places like Germany or the Northern and Eastern United States, it could provide lots of power in places like the Arabian Peninsula, or the U.S. Southwest.
Technology is definitely making progress towards better solar cells. The big problems now are storage and reducing transmission losses, so you can store enough surplus power during the day for use at night and cloudy days (which, for the Arabian peninsula, isn't going to be many days a year, at least), and don't lose too much power during transmission.
It's $/kWh that is the primary measure. kWh/m^2 is important for site installation, but not nearly so critical as $/kWh for market entry.
If it's cheaper per watt, someone will find a site for it.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
The article says 80% improvement ... so, if solar voltaic cells are 20% efficient, then 80% more brings that up to 36% efficient. That's a big deal, provided it doesn't cost 80% more, but it isn't 80% efficient. There are already solar cells with about 30% efficiency, but nobody buys them because they cost 100x more.
https://secure.wikimedia.org/wikipedia/en/wiki/Solar_cell_efficiency
Efficiency does matter. It won't help you if someone invents solar cells which cost 1 cent per megawatt, but have an efficiency of 10^(-20) (yes, I can also make up ridiculous numbers :-)).
The Tao of math: The numbers you can count are not the real numbers.
Actually, based on your statement you do care about the efficiency. It's just, I think, that your threshold for efficient enough is tied up in your projected use of the technology. What they are talking about is effectively doubling the wattage that can be collected from the dirt ass cheap solar cells. The base material in question is cadmium telluride which can be produced cheaply enough to compete on a cost/watt basis with silicon based photovoltaics. What this researcher has done is shown a nearly factor of two improvement in what is already the most cost effective photovoltaic cell for large installations, which is a great big deal.
how about... most of the products people use for that now? i love hearing people say "blah blah... doesn't work... to expensive..."
the panels on my mothers house, non subsidized, work great. the system on our church works great, as well. my new system will be making me money in less than six years... (that's total NET profit, btw)
so unless you live in a cave or in a building shaped like a giant pencil i don't understand why you hate the sun so loudly.
"efficiency doesn't matter to me at all. "
To prove you wrong, I will quote... you.
"But show me one that is cheap enough to afford to cover my roof with "
That is Price / watt.
"that the end total wattage is enough to cover something close to my power use "
That is Watt / m^2.... also know as Efficiency.
As you have correctly, and incorrectly pointed out, efficiency does matter.
$/kWh determines market adoption.
Watt/m^2 (after market adoption) determines sales channels and installation sites.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
Since it's obviously too much work for the poster or editors to put TFA in context, I went to Wiki and pretty much learned what you posted. Oy.
Never let a lack of data get in the way of a good rant.
... is one of those Green cheerleaders who are fond of hyperbole, like Al Gore and the entirety of the IPCC.
nope. you can reduce the size by 55%
Really? And if they improve the efficiency by 100%, I don't need any solar cells at all to get the same power? (100% less!)
Actually, with 80% more efficient solar cells, you could reduce the size only by about 44% to get the same power.
The Tao of math: The numbers you can count are not the real numbers.
There are multi-junction solar cells with a decent efficiency. That's teh kind that go on expensive sattelites. The problem is that such cells cost an arm and a leg so it is still cheaper to use the single-junction cells that get a much poorer efficiency. The kind of solar breakthroughs that might make photovoltaic competitive is reductions in the cost of teh manufacturing process. If you can find a cheap way to make the multi junction cells then the price per kWh will come down drastically.
Btw: The price per watt is useless as a metric because most of the time the cells don't give you their maximum power rating. What is interesting is the price per unit of energy averaged over a year. I.e $/kWh.
The cadmium telluride is 0.5 micrometers thin, so there isn't actually that much of it.
It's nuclear powered and produces lots of dangerous, cancer-causing radiation. :-)
The Tao of math: The numbers you can count are not the real numbers.
When it's 3.2% efficient (compared to 1.8%), then it's not so impressive.
I think the bigger question is...
Will It Blend?
when they have this?
"National Security is the chief cause of national insecurity." - Celine's First Law
Just as soon as we work out the patent license. :(.
Hi! I make Firefox Plug-ins. Check 'em out @ https://addons.mozilla.org/en-US/firefox/addon/youtube-mp3-podcaster/
Wasn't there some other article posted here a year or so ago about the problem of one photon equaling one electron being the problem and that someone had discovered something that created a cascade effect so that one photon could become more than one electron? When are we going to see that on the market?
Price per watt is the end user's opinion of usefulness. You cover your roof with cheap inefficient crap and pat yourself on the back for being "green". Yet these technologies have quite the carbon footprint involved in the manufacture of solar panels. When you take the efficiency into account you can potentially reduce this footprint. Some made up numbers for your understanding:
10x 1m^2 panels, producing 10kW consumes 10MW during manufacture, and costs $1000 per panel. vs
1x 1m^2 panel, producing 10kW, consumes 1MW during manufacture, and costs $10000 per panel.
In this scenario you break even but the environment and the amount of realestate you consume is far better off. Then you can really pat yourself on the back.
If I could get anything "solar" that would have a six-year payback I'd do it. Unfortunately, here in Arizona (plenty of sun!!) it looks like the best that can be done is 15-20 year payback with a cost of around $30K. That is absurd from my point of view. The house probably will not even exist in 20 years. The lifespan of the developments that were built around 2005 or so are going to be very, very limited and they might as well just plow everything back into farmland. Nobody's house is worth more than about 75% of the mortgage which means they pretty much can't be sold for another 25 years or so.
When the neighbors start leaving and abandoning their houses I'm probably going to go as well.
So putting up something with a 20 year payback is silly. Oh, and that is with the electric company and tax rebates paying half of the cost.
So those crappy auto recharge panels I bought on clearance last month are almost twice as good now? How'd they do that from 2000 miles away? Wow, I gotta go plug 'em in!
I'm appalled at the ignorance on the thread regarding the current state of solar.
1st generation solar panels are already viable
- Panels are readily available for $1.70/W
- $3.50/W to install. Installers are making a killing but that's American labor for you
- Don't know where you live or what your roof looks like but here in CA it's easy to get 80% power generation for your home with a 7 year payback
- Reliability of panels easily meets the 25 year warranty now
- Efficiency climbs at about 1% absolute (3-4% relative) per year
- Prices have dropped dramatically. In 2008 alone, panel prices dropped 40%. This was mainly due to China coming online
It's easy to bash outlandish claims made by flavor-of-the-month technologies but the fact is 80% of the market is 1st generation solar panel tech. And that's not changing soon because it is more than adequate for meeting everything that everyone complains about solar not being.
People just want to complain and look smarter by trashing the proverbial straw man.
Not always. For some things it will be what it was decades ago - watts/kg or watts/mm^2. That may even matter in consumer space. The solar powered mobile phone might not be far off since the simple models don't consume a lot of power, and for applications like that paying a bit more for something that will actually fit on the back of the phone will be worth more than not having the feature at all. Also we already have photovoltaics used at the focus points of mirrors and expensive cells with a few mirrors could end up cheaper than a big flat panel of cheaper cells, or simply more useful since it's easier to track the sun with small stuff.
It's not that stupid to consider that we may be moving a lot of personal transport in large cities to the equivalent of lightweight electric golf carts in a couple of decades - if not where you are most likely in China and a pile of other places with air like 1950s London's green fog. Even though most of them will sit parked in the sunlight all day that's not a lot of surface area to play with if you want some sort of solar recharge.
Dollar payback is going to depend on whatever strange things your local power company is doing and how much the equipment you buy costs. In some parts of Australia due to a government handout and power authority handouts the dollar payback time is close to immediate but that's really a short term token effort by various groups pretending they are green by handing out relatively small amounts of money instead of building something big and capital intensive. That's effectively spending the money like advertising money and won't last long.
For dollar payback you'll have to work that out yourself and it will depend a lot on what artificially high price is being charged for electricity where you are and what artificial inducements a government will give you for doing it. That number will be horribly rubbery which is why "energy payback" is used. Personally I still see photovoltaics as being an off grid solution for places where it's too expensive or inconvenient to connect to the grid or in places where the electricity is so unreliable that they effectively replace a diesel generator. A lot of getting panels on suburban roofs is more about looking "green" than any sort of actual effort in improving electricity generation or efficiency. It's advertising. A large solar electricity generating plant in comparison requires a lot of capital and a bit of risk as well as a lot of of political infighting with deeply entrenched lobbyists. Photovoltaics are not really in that game because solar thermal scales up far better.
"so what,"
This research is a proof of principle for a new solar cell design. It is the first step taken which shows that conical design has the potential of increasing solar cell energy conversion efficiency.
"why would I build a cell out of this material when conventional silicon beats the living crap out of it,"
Conventional silicon solar cells are undesirable due to a number of problems with the use of silicon in photovoltaic applications. The main concern is that crystalline silicon solar cells require silicon in bulk quantities. This issue alone doubles the cost for crystalline silicon solar cells compared to those based on poly-crystalline CdTe (2-7microns).
"how do you plan to produce this on an industrial scale,"
Both CdTe thin films and ZnO nano structures are already producible on an industrial scale. All that remains is the adaptation of this particular conical geometry.
"will this ever see the outside of your lab,"
They are not the only research group working on similar research. Implementation of ZnO (and other oxides) nano structures is a hot topic in current photovoltaic research.
"you need some published articles in order to get promoted, don't you?"
This statement is true of any research group working on any research topic. Lack of publications results in lack of research funding.
Like has been said - I assume your costs for nuclear included disposal/storage of waste material and cost to mine - not based on raw consumer cost after government subsidies. With coal-based electric, I am also assuming you figure that gas and mining costs will remain static over the repayment period and will not see an increase due to increasing scarcity (although I have seen my gas at the pump going up a bit lately). Really, if you want to compare cost - don't compare just the utility payment as the cost to generate power - many fossil fuels and nuclear power has a significant amount of government money put into it, and that means tax dollars. In the US you can look at the boom-bust cycle of wind and solar and see it matches with the loss of the Production Tax Credit that congress lets slide every year - do the same to oil and nuclear power and you will see the same collapse in the industry. Maybe its time to give alternative energy an even footing in the marketplace.
On one hand you're saying you don't care about efficiency, but on the other you've put constraints on acceptable efficiency by stipulating the size of the array and the wattage. Efficiency matters, both because not everyone has an acre they can cover with cells and because there are costs that scale with the size of a solar cell array.
More to the point, they're now selling turnkey solar panel setups at Costco. I think we're near the start of a wave of solar everywhere.
The per-panel or per-square-meter overhead is not irrelevant, and thus efficiency is not irrelevant.
This is true, but the cost per square meter for a collector is baked into the cost per kW, so kW/$ is still the most pertinent metric. :)
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
Let's get the facts straight:
"With this approach at the laboratory scale, Xu and colleagues were able to obtain a light-to-power conversion efficiency of 3.2 percent compared to 1.8 percent efficiency of conventional planar structure of the same materials."
3.2% is pathetic. A quick Google search reveals some polycrystalline Cadmium Telluride cells developed by the National Renewable Energy Laboratory that achieved 15% efficiency. It was published TWO YEARS AGO.
For once, FOR ONCE I'd like to see a genuine solar cell breakthrough that changes the industry. Not some BS press release that's only a thinly veiled attempt to generate some capital investment. I understand that science usually progresses in baby steps (especially in chemistry) but there's got to be a higher standard for informing the public about your research.
Right, the cell is composed of cadmium telluride, which is a binary compound. That is different from saying the cell is composed of cadmium and tellurium, which are separate atomic compounds with different properties. Toxicity and fire studies on cadmium telluride are ongoing, but so far they have found that cadmium telluride is not much of a threat. In fact, there was a chicken farm with cadmium telluride solar panels that burned down in Germany in late 2009, and while the place was treated by the authorities as a hazardous waste site, it was because of the chicken poo, not the cadmium telluride -- the burnt panels were collected and sent back to the manufacturer for recycling.
Put another way, assuming cadmium telluride is toxic and stinky just because it is composed of toxic, stinky elements is like assuming water is explosive because it is composed of explosive elements.
You know, some people are actually interested in research, not in current market value. Just because you are insofar typical for the main population that you don't give a fuck about anything beyond your very tiny horizon doesn't mean that people working on alternatives qualify as "clowns". You, on the other hand, would - if only you were funny and not just pathetic.
Ubi solitudinem faciunt, pacem appellant.
Really? The cost per square meter for me to build more heliostats to make up for a lower efficiency is baked into the cost of the panels? I think not. ;)
"Lock and load, Brides of Christ!"
From the article: "With the creation of a 3-D nanocone-based solar cell platform" You're missing the whole point of the article. You're missing the progress made possible by the 3D chips. How many of the current solar cells technologies are using 3D chips ? Thanks for the "clown".
Plese read the article. The research team successfully applied 3D synthesis models (and their nanocones) to solar cell. Meaning higher efficency and cheaper costs. Just by going 3D instead of 2D. "Key features of the solar material include its unique electric field distribution that achieves efficient charge transport; the synthesis of nanocones using inexpensive proprietary methods; and the minimization of defects and voids in semiconductors. The latter provides enhanced electric and optical properties for conversion of solar photons to electricity." "Because of efficient charge transport, the new solar cell can tolerate defective materials and reduce cost in fabricating next-generation solar cells."
Dollars per square meter (or perhaps kilowatt-hour) is the only really relevant measure. Once it's cheaper to make electricity this way it will take off.
Limited by the fact that maximum solar power is a bit over one kilowatt per square meter. How much does real estate cost? Or transmission lines from somewhere the price of land is low enough?
Also limited by the fact that the sun does not shine all the time. Solar power at zero cost is useless at night if you don't have cheap enough batteries.
No, of course it's not baked into the cost of the panels. It's baked into the cost per kW metric, though, because the costs of the panels, heliostats, land etc. are all part of that cost. Efficiency is certainly relevant, but it's only part of the equation. That's why some of this research into 5% - 10% efficiency technologies is so exciting - because even though it's far less efficient than current state-of-the-art, if you can pump it out at $5/sqm it's the most cost-effective way to generate electricity.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
For The Oak Ridge Boys!!!!!!!!!!!!!!!!!!!
As BlueParrot wrote, conversion efficiency improvement in a cell is nice, but how much does it cost to manufacture? Thin-film is less efficient than silicon PV, but so much cheaper to manufacture that that's why it is spreading. But even adding manufacturing cost improvements to conversion efficiency is not sufficient.
What researchers, federal lab and university press offices, and apparently news editors, seem to forget about solar energy is that the most stubborn costs are in the "Balance of the System" or BoS, which have not improved much over the years, and as the cell costs have declined, have reached over 50% of the total cost -- and are still climbing. That's racking, labor, wiring and financing, to name a few parts. Rocky Mountain Institute conducted a charrette last year which identified some of the causes (Part of the problem is that each system install is custom -- every roof, building, patch of ground is different.), and then came up with ways to lower the costs significantly...at least theoretically! Here's a link to the RMI page where you can find the full report or the executive summary: kF8dgH
Currently the solar cells have an efficiency 20%, if the news is true, the efficiency will be 80%!! efficiency =electricall energy/solar energy if you have solar energy in 1 square meter=100 Wh with the currently solar cells you have an electricall energy of 20 Wh, with the new solar cells you have 80 Wh. This means that with the same electricall energy, I use a smaller surface than 75%!! It will be beautifull When it will be donne.