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Clean Power nanowire crystals

Published on March 25th, 2013 | by James Ayre

84

Theoretical Limit Of Solar Cell Efficiency Probably Broken

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March 25th, 2013 by
 
A simple, single nanowire crystal is capable of super-concentrating the intensity of the sunlight that it is exposed to up to a factor of 15, researchers from the Niels Bohr Institute have discovered. The surprising discovery means that the assumed limit to solar cell efficiency, the “Shockley-Queisser Limit,” can likely be increased. The discovery should lead to new types of high-efficiency solar cells, but also will have uses in potential quantum computers and other electronics, the researchers say.

nanowire crystals

Image Credit: Niels Bohr Institute



 
Nanowire crystals are, basically, “a cylindrical structure with a diameter of about 10,000 part of a human hair.” The researchers involved in this discovery had been spending the past couple of years developing them, and working to improve their quality.

During the research, it was discovered that “the nanowires naturally concentrate the sun’s rays into a very small area in the crystal by up to a factor 15. Because the diameter of a nanowire crystal is smaller than the wavelength of the light coming from the sun it can cause resonances in the intensity of light in and around nanowires. Thus, the resonances can give a concentrated sunlight, where the energy is converted, which can be used to give a higher conversion effeciency of the sun’s energy.”

As a result of this discovery, the theoretical solar cell efficiency limits will very likely have to be increased. While that may not sound important, it should have a significant impact on the development of future solar cell technology. It will probably still be a couple of years until this discovery results in the production of ultra high-efficiency nanowire solar cells though, according to the researchers.

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About the Author

's background is predominantly in geopolitics and history, but he has an obsessive interest in pretty much everything. After an early life spent in the Imperial Free City of Dortmund, James followed the river Ruhr to Cofbuokheim, where he attended the University of Astnide. And where he also briefly considered entering the coal mining business. He currently writes for a living, on a broad variety of subjects, ranging from science, to politics, to military history, to renewable energy. You can follow his work on Google+.



  • Guest

    Hans; Well put. What about ‘plasmon gates’? Can these artificially amplify photons passing through a nano-crevice to match a material’s bandgap?

  • Jetik Jetik

    Nuclear power = super efficient, high-producing, and potentially super-deadly
    Solar power = nuclear power being poorly harvested from a huge reactor

    I think progress would be in the form of pursuing research into nuclear power, as solar power is just a branch science of this anyway.

    • http://twitter.com/aligatorhardt aligatorhardt

      Bullshit. Solar power is collecting free sunshine. Nuclear power is a doomsday machine.

      • Jetik Jetik

        You do realize how sunshine is made, don’t you?

        • arne-nl

          Exactly, safe, at 150 million km distance. No refueling needed for at least another 4 billion years.

        • http://twitter.com/aligatorhardt aligatorhardt

          Sunshine is not made by men with overactive imaginations and underactive responsibilities. Enough with invalid comparisons. It just makes you sound like a con man.

    • Bob_Wallace

      Well, we’ve been pouring money into nuclear reactor research for over a half century and the price keeps going up while the safety/waste disposal issues stay unsolved.

      Solar, on the other hand, has received far, far less research money and its price keeps dropping. There are no safety issues.

      Seems like the smart thing to do is to go with what is working and drop what isn’t. And that’s what is happening. Many countries are walking away from nuclear and solar installations are booming.

      Perhaps you should look at solar as the nuclear problem solved. Safe, cheap and quick to install.

  • http://www.facebook.com/bob.crowley Bob Crowley

    We reported this effect in 2006 and I have tried to post a link to the work here. The nanowires act like antennas raising both current and voltage at the junction with the PV cell enhanced by nonlinear charge transport across the junction. I have 11 patents on the base technology and am very pleased to see my work validated once again.

    • http://zacharyshahan.com/ Zachary Shahan

      not seeing the link. try again?

  • http://twitter.com/RobotPiratNinja Wah

    Hey, your ridiculously obnoxious popup ad makes it impossible to read the story. Way to web design like an idiot.

    • Noone you care about

      I just clicked the X in the corner of the ad. Annoying? Yes. Impossible? No.

      • JustSaying

        But would be a lot fast of all the banner add were in a boarder so as you go from story yo story they don’t have to reload each time. At least for those of use you want to read the stories and not just the teaser on main page. Also if the the ads didn’t have to appear over every graph.

    • http://www.facebook.com/chadericstevens Chad Stevens

      Adblock Plus bro. Its free, no popups, no adds. http://www.adblockplus.org

    • http://zacharyshahan.com/ Zachary Shahan

      it pops up once. and has a very easy to use ‘close’ button. our focus is getting people to switch to cleantech. if you don’t like that, feel free to ignore us.

  • Jon Fisher

    Are you guys kidding me? I don’t care how much energy a nano-wire sucks in from sunlight, simply because sunshine is not available long enough, and intense enough, to make this technology a viable alternative. And except for the hot air coming out of Washington DC, wind power is only effective where the wind is actually blowing consistently. Clean coal is possible, and simply needs to be mandated, especially in China. Nuclear power plants can be built away from population centers, and with greater emphasis on emergency shut down procedures and technology.

    However, this discovery, if it is real, would be great for satellites, Florida, and Asian manufacturing. Obviously the Chinese will steal the specs from whoever completes the research and then sell us the product with a warranty of 3 months, after which the nano-wire will decompose. We have a chain of stores in America called Suckers-R-US; or is it called Wall*Mart?

    • PlayerNumber3

      I see the light. All electrical energy in the US should be produced by a single technology. The nation should immediately buld 400 new nuclear plants, or 1000 new coal plants.

    • Bob_Wallace

      The Sun doesn’t shine all the time. The wind doesn’t blow all the time. Lots of hydro systems don’t have enough feed-in water to run 24/365.

      Nuclear reactors shut down about 10% of the time for fueling and maintenance Coal shuts down about 15%. Plus both of them shut down additional time for repairs. Sometimes reactors are down for years.

      Loads vary constantly.

      The grid deals with these variable events.

      Wind is now our second cheapest source of new electricity. As its price continues to drop and the price of natural gas creeps up it will become our cheapest. Solar is on the way to be the second lowest. Grid operators will fill in around the cheapest two with more expensive electricity from other sources.

      Clean (carbon capture) coal would be very expensive. Probably over 20 cents per kWh. New nuclear would also be very expensive, at least 12 cents and possibly over 20 cents, They make no financial sense.

      Additionally both basically have to run 24 hours a day. Takes too long to start and stop them. That means that when there is cheaper wind or solar available coal and nuclear have to sell at a loss in order to force wind or solar to curtail. Run a big hunk of the day at a loss and you need to price your demand hours much, much higher than your calculated “average” price.

      Coal and nuclear just make no financial sense.

    • http://twitter.com/aligatorhardt aligatorhardt

      Why is it nuclear cheerleaders always lie about renewable energy? Must be because they know there is no reason to choose nuclear power when it cost more, and damages all forms of life in irreversible ways, uses huge amounts of water and contributes direct warming to the atmosphere and water ways.

  • tommariner

    We’re going to get to boundless energy — sooner rather than later. If we listen to non-partisan scientists rather than failed politicians or friends of an Administration. (Sorry, still can’t believe that we let the investors in Solyndra steal the government money within weeks – the rule of venture capital is “those who are in, stay in”.)

    • Bob_Wallace

      Perhaps you should educate yourself about Solyndra and the overall success of the program which funded it.

      Not every attempt succeeds. Anyone with any experience in business knows that lots of good ideas (along with many bad ones) fail. Sometimes it’s because of bad implementation. Sometimes it’s because competition comes out of nowhere (as in Solyndra’s case) and takes the market.

      • tommariner

        Bob, I did educate myself about Solyndra — I have spent time as a Venture Capitalist. I love green energy and hate burning rotten dinosaurs to keep the lights on and cars going. I believe in the government or somebody funding research at an early stage when it is not economically feasible, but needed.
        The Solyndra project was sold to an unsuspecting President and staff as a ready for market, commercialized venture. Any due diligence by even an incompetent would have revealed that it was not ready for prime time to ship large quantities of product. I would not have expected an instant return or maybe any at all, but the friends of the President violated the golden rule of venture — “those who are in, stay in”. That makes sure that the money invested is used solely for the purposes to which it was stated to be used and not to let the early investors pull out with a profit while firing thousands of workers — which is what happened in the case of Solyndra.
        A President Romney would not have made that amateur mistake and America would have large quantities of solar generation. The China competition is manageable and predictable — a competent executive would have succeeded — those guys stole the money and ran literally months after the loan guarantee hit the bank.
        I want clean energy and government incompetence stole that from me — and you. you’re not upset at that??

        • Bob_Wallace

          With hindsight we can that President Bush should not have pushed his DOE to approve Solyndra. And do remember that they would have approved the loan guarantee prior to Bush leaving office except that the paperwork was not complete. A few weeks after Bush left office the exact same group of people who held up funding under Bush gave the final approval when the completed application was returned.

          And hindsight also shows us that Solyndra was apparently promising more than they could deliver. However this was not being questioned at the time. The conservative financial press was heralding Solyndra as a great American company that was going to play a great role in energy.

          Now would a President Romney have killed Solyndra? We have no evidence that he would and are left with a large suspicion that he would not.

          Mitt Romney is not a very bright nor insightful person. He hears what he wants to hear and surrounds himself with people who make noises pleasing to him. That suggests that he wouldn’t have questioned Solyndra. After all, the very wealthy Walton (Walmart) family were investors and one must stand with their rich friends (as long as one isn’t risking personal money).

          Look at Mitt. He thought he was going to win the election and was ready to light the fuse on his enormous fireworks display when the outcome was announced. The rest of us knew he was loosing long before the votes were cast.

          Mitt only became rich because he was a rich man’s son who was gifted with a golden goose. Other people at Bain identified a new way to make money and handed it to Mitt. He didn’t even fully understand nor have faith in the idea and demanded a fail safe net rather than taking a unique opportunity and running with it.

          He hired some bright, capable people who did the real heavy lifting and the company pumped money into his account. Mitt was born on third base and bum rushed to home by the actual talent that pushed him along because he was standing in their way.

          America avoided another Republican presidential catastrophe Nixon, Reagan and the Bushes did enough damage to our country. We luckily didn’t to drive ourselves totally under by making the Mitt Mistake.

        • http://twitter.com/aligatorhardt aligatorhardt

          What a load of nonsense. Worshiping Romney is where you really reveal your lack of sense, or honesty. A loan program with over 98% success can only be called a failure by a Rethuglicant. There is nothing wrong with the Solyndra design, it just is not low bid. The cost of competing products dropped, and left Solyndra at a higher price point.

          • tommariner

            Not “worshiping Romney” –just statement of the fact that he would not have made the bone-head move we did on Solyndra. The issue isn’t partisan political — just an appreciation of a new nano-wire solar technology that will help get us the energy independence we deserve.
            The issue is that those who got the loan guarantees stole the money, fired the people, closed the place down and wasted the technology. I hope you’re nowhere near business — the designs are always the best, the competition is always lower in price, and management always knows about it and should weather the storm — an experienced business guy in the White House would have made sure the loan money kept paying off for a green America. (Its more than a campaign speech — we really can do it.)
            Of course we’ll get to abundant clean energy — if we stop the political campaigning and get back to innovative America.

          • Bob_Wallace

            You really ought to take a closer look at who Romney really is.

            He’s just not a very bright dude. He, like Bush, was born with a huge head start and, like Bush, other rich people gifted him with an easy road to very big money.

            BTW, the CEO of Solyndra was a Republican. Just thought you ought to know….

          • tommariner

            Bob — this blog post is about squeezing energy from every photon from the sun. Its not political. I wouldn’t care if the CEO of Solyndra was Buddhist / Roman Catholic / Libertarian — he failed his country and his company.
            And that not-very bright dude graduated from Harvard with both law and MBA degrees.
            But I am a proponent of even more computer control of particularly the aiming of the photodetectors — we have gotten some amazing results from coordinated micro mirror “telescopes” and see no reason why it wouldn’t work here. And potentially changing the wavelength — we use “scintillators” to modify frequency / wavelength to what a detector likes better.

          • Bob_Wallace

            That’s true, Tom. This article is about a possible breakthrough in solar capture. And then someone named Tom started off on a tangent about Solyndra and Romney.

            Solyndra basically failed because something better came along and took away their market. Typewriter manufacturers and Kodak film failed for the same reason. The major manufacturers of slide rules closed down within two years of scientific calculators hitting the market.

            I didn’t say Romney was stupid. But if you actually paid attention to him as he ran for the presidency you would have realized that he’s not exceptionally smart. He won the Republican candidate position simply because the competition was a car full of clowns.

            Romney would have backed fossil fuels had he gained office. Or maybe he wouldn’t. Can’t base what he will say on day two based on what he said on day one.

          • tommariner

            I know Kodak and helped invent calculator chips. Never because of something better! If the companies you’ve managed failed for that reason, your board deserves to be fired. And if you stole the investment money you and they deserve to be in jail.
            My personal opinion, not connected to any organization.

          • Bob_Wallace

            I don’t understand your post.

            But if you actually know Kodak you know that they did a lot of the heavy lifting in the development of digital photography but made a bad decision to stick with film as their major activity. That cost them market dominance and ruined the company.

            Stealing investment money is a serious charge. I have a lot of problems with how much some CEOs make, especially how many of them leave a troubled/unsuccessful company with a bundle of cash, but that’s not theft. I wish there was a law against people at the top failing and still making a fortune but there is not one.

            We need a major adjustment in some of our business practices. We’re paying people at the top far to much and people at the bottom too little. That, if left unchanged, will destroy our economy. If we don’t do a more equitable distribution of the gains we will destroy the market. People who make only enough to barely feed themselves and their families can’t buy the products they produce.

            The Board and CEO of Kodak screwed the pooch. They should have left their positions with an empty pay envelop. The money they got should have been distributed to the employees who had nothing to do with the failure but had to look for other employment.

            It’s not about redistributing wealth. It’s about fairly distributing gains.

  • Conrad Quackles

    Imagine the day when we have portable solar-powered quantum computers. I’ll be an old geezer but I’ma still buy one.

  • http://twitter.com/aligatorhardt aligatorhardt

    The so called natural laws have been shown to be incomplete many times, and completely wrong a few times. While it flatters a scientist to think that they have figured out a big question, seldom is anyone capable of total understanding, and making these “laws” can actually discourage new knowledge. Never stop asking questions. There is no “last word” in science.

  • Drago

    Idiotic. Where are the physicists when you need them … Oh wait I’m here.
    Mindless sheep running after phantasms, such is the gullable modern secular dumbed down mind..

    • Marshall Harris

      Do you have anything useful to contribute or did you just want us to read your rant?

    • Godwinslaw

      The term secular is antithetical to science.

    • http://zacharyshahan.com/ Zachary Shahan

      if you want to explain why it’s stupid, it’d be great if you wrote something useful. and in all seriousness, if you are upset about people not being specialists in the field you’re supposedly a specialist in, perhaps try informing people in a friendly and productive way. or just live your life in bitter misery…

  • bglick4

    This is very good. I’m very optimistic that, in another ten years, solar will be a viable energy alternative. It still makes me angry when taxpayer dollars are wasted on building solar power stations now when we are so close to a marketable technology. It would be like subsidizing computers in the sixties so everyone could have one. Wait for the tech. It will be here soon enough.

    • http://twitter.com/aligatorhardt aligatorhardt

      People have been saving money with solar power for many years. It will undoubtedly be better in the future, but there is no reason to wait. Most who claim solar is not ready are liars or dupes.

    • PlayerNumber3

      The worst part is this righteous solar anger takes up room that could be used on super-righteours petroleum anger, when taxpayer money is spent fighting wars and bullding weapons to protect foreign sources of oil.

    • Hans

      You are suffering from the “lets wait for the better technology from the future syndrome”. You forget that this better technology from the future is only partially developed by people in the lab. A very big part of technology development is learning by doing. The mind-staggering cost drop of photovoltaics is mainly due to improvements in production technology and upscaling of production which were the direct consequence of the (subsidised) application of PV. Rate payers euros were spend well.

      • Bob_Wallace

        And right now the costs of solar is not the cost of the panel.

        US installed solar is running about $3.50/watt average. German at $2/watt. Only $0.60 or so of that $2 to $3.50 is panel cost.

        The big hurt right now is BOS (balance of system) costs. That’s where we need to look for price improvements, not in panel costs. Panels are already reasonably priced and will continue to drop as manufacturers find innovative ways to further cut costs.

        In the US we are paying too much for permits and inspections. For “customer acquisition” and sales cost. Our profit per watt is much higher than Germany’s. (Likely their companies are doing OK because they are installing more volume.) We need to shave our non-panel costs.

        That will happen.

    • Bob_Wallace

      You think we didn’t subsidize the development of computers which led to the PC?

      I personally spent around $100k in federal grant money to buy a mini-computer when I had zero use for it at the time. Every lab in our university bought one and then looked for applications.

      The federal government purchased a lot of hardware as a way to give computer companies some income so that they could keep developing.

      Subsidizing minis led to the “computer on a chip” that let the Woz build the Apple.

      Solar in Germany is now getting installed for less than $2/watt. That’s a non-subsidized price. $2/watt would be eight to ten cent per kWh in the US.

      If you can make your own electricity for ten cents or less and do net exchange with the grid you’re going to be doing fine. And don’t forget, that eight to ten is locked in. Grid prices will go up and your electricity cost will not. And after the system pays for itself your power is free. Most likely more than 20 years of free electricity.

      Subsidies have helped bring solar from around $100/watt 30 years ago to now just above $0.50/watt. That’s a 200x price drop.

      Subsidies have helped bring wind from $0.38/kWh to under $0.03/kWh. That’s also a huge price drop in the range of 12x.

      We’ve invested billions and billions and billions more into fossil fuel and nuclear and their prices keep going up.

      Doesn’t take a financial investment expert to tell which investments have paid off and which haven’t.

    • http://twitter.com/aligatorhardt aligatorhardt

      A common talking point of fossil fuel powered liars is the claim that renewable energy is not ready, every year. Anyone who reads the news can see that is crap.

  • http://www.facebook.com/nicholas.kotze.5 Nicholas Kotze

    “It will probably still be a couple of years until this discovery results in the production of ultra high-efficiency nanowire solar cells…”

    Unfortunately it’ll probably “get buried” among the glut of lesser breakthroughs and/or take decades to be recognized/developed/affordably mass-produced before it can contribute significantly toward relieving our energy crisis and CO2 emissions. Our children or their children will likely have cheap, powerful/efficient solar panels derived from this marvellous breakthrough covering their houses, office buildings, road surfaces, cars etc, but not us, sadly. I hope I’ll be wrong.

  • http://www.facebook.com/MikeBlockCPA Mike Block

    Here is the article from the Niels Bohr Institute in Nature Photonics http://www.nbi.ku.dk/english/news/news13/nanowire-solar-cells-raises-efficiency-limit/
    You also can see it in Science if you want to pay for it
    http://www.sciencemag.org/content/339/6123/1057.abstract

    • anontheist

      “The research is conducted in collaboration with the Laboratory des
      Matériaux Semiconducteurs, Ecole Polytechnique Fédérale de Lausanne, the
      Foundation and the company SunFlake A / S. Their scientific findings
      work support results published in the journal Science in January. Here, a
      group of researchers from Lund, showed that the sun’s rays was sucked
      into the nanowires due to the high amount of power that their solar cell
      produced.”
      SAY WHAT?? “THE SUN’S RAYS WAS SUCKED INTO THE NANOWIRES”.
      “SUCKED IN”? Really? I think this whole report sucks.

    • Hans

      I have skimmed the Sciencemag article. The “Shockley-Queisser Limit” is not mentioned at all! From this quick reading I understand that: 1) by changing the dimensions of the nanowires their solar cell made a jump in efficiency compared to other nanowire designs and now approaches the efficiency of standard solar cells. 2) the experimental results cannot be explained by simple ray optics*, but a 3D electromagnetic model is needed to describe how the light behaves between the nanowires.

      So the shifting of the Shockley-Queisser Limit is either somewhere hidden between the lines, or the PR guy of the Niels Bohr institute made the story a bit more spectacular than it actually was.

      *The kind of optics you learn in secondary school, where light is only reflected, absorbed or refracted, but complex electromagnetic interactions are ignored

      • Hans

        So I call upon the Cleantechnica writers to overcome their apparent shyness and to contact the original researchers for some extra info.

  • Zer0Sum

    If we are talking about resonance can it create feedback too?

  • http://profiles.google.com/andrea.david.edelman Andrea David Edelman

    Damn I was really hoping we would be able to stay on nuclear and coal. Oh well, too bad.

    • Kevin Birge

      I wouldn’t lump nuclear and coal together. The two aren’t even analogous. I come from a coal producing region. You can see where the surface mining was done. The land can be reclaimed from that. How will you reclaim the likes of Fukushima?

      • bglick4

        I like nuclear and clean coal. They are both excellent energy sources, however, solar will be the best source, once the technology is advanced enough. It won’t even be close.

        • Ross

          Clean coal is a marketing term; it doesn’t exist.

        • Jetik Jetik

          You do realize that solar power is just a form of indirect nuclear power, right?

          • Bob_Wallace

            Solar is how we solved the safety and waste disposal problems of utilizing nuclear energy.

            Well, wind and hydro are a couple other ways to safely and affordably use nuclear power.

            Too bad we wasted all that time and money trying dangerous approaches.

          • Jetik Jetik

            Solar may be a great temporary solution, but the raw power of nuclear energy is too d*mned sexy. Why would we ultimately settle for scraping up the little energy that hits us from the sun when we can generate that same energy on our own…. well, scale-downed a bit.

            Imagine Antarctica covered in huge nuclear plants with giant power lines carrying that energy over to the rest of us. If there is any sort of problem at one of the plants then screw it, it’s Antarctica; no one lives there anyway.

            The only people hurt would be the tree-huggers crying for the penguins. We have pills for that.

          • Bob_Wallace

            Nuclear energy does make a few people get all tumescent but not the ones who make decisions based on numbers.

          • green meenie

            Troll Alert!!!

          • http://zacharyshahan.com/ Zachary Shahan

            Jetik: 1- the issue of cost simply prices nuclear out of the market — it’s too expensive. get over it. and if you work in the nuclear industry and are quite young (unlikely), you might reconsider your career path.

          • http://zacharyshahan.com/ Zachary Shahan

            you do realize that nuclear fusion on the sun is a world of different from nuclear power plants on earth, right?

      • Eric Smith

        Apparently sarcasm cant be reclaimed either lol

      • Yep

        Downtown Nagasaki and Hiroshima were reclaimed with 50 year old technology. Fukushima will be as well.

        • Ross

          That doesn’t make it alright.

      • cray74

        Fukushima’s land will be reclaimed in a few years, since it didn’t release nearly as much in the way of lingering isotopes as Chernobyl. The most problematic is Cesium-137, which has a 30-year half life, but currently very little settled in the area. Radiation badge testing and regular soil sampling is showing that radiation levels are quite low, and no illness has been observed among residents and plant workers.

        21 Americans died in the coal industry in 2011. No one died from Fukushima in 2011.

        • Bob_Wallace

          Fukushima is going to cost Japanese taxpayers upwards of $250 billion to clean up. A broken solar panel would cost peanuts.

          A bunch of people died at Chernobyl. No one has died from standing too close to a malfunctioning solar panel.

          Best you don’t try to claim that nuclear energy is safe. The stuff is deadly dangerous. That’s why we have containment domes, all sorts of emergency shutdown/cooling systems, armed guards, fighter planes standing by to intercept off course airliners, etc. Not to mention millions of tons of radioactive waste, some of which will be a danger to humans for thousands of years.

        • Ross

          You’re losing when you’re explaining that nuclear isn’t really that dangerous if you understand the risks and take appropriate safety precautions.

        • green meenie

          hey, and when they’re done cleaning up there, maybe they could be sent out west in the US (Utah?) to clean up the massive area of toxic tailings left behind from uranium mining. after that, they could go to work at Hanford.

    • http://zacharyshahan.com/ Zachary Shahan

      wind and solar are already closing them down. the question is really just the speed at which it happens.

  • Hans

    The Shockley-Queisser Limit is valid for solar cells with single p-n junction with a single uninterrupted bandgap. Its principle is very simple: To excite an electron from the valence band to the concduction band a photon needs a certain amount of energy. Some of the photons will not have enough energy (infrared), so their complete energy is lost. Some of the photons will have too much energy (UV), and their surplus is wasted as well. Concentrating the light will not change this fact.

    Most likely Nathan did not understand the original source really well, reworded it a bit clumsily, or Nathan read a version of the news that has already been echoed around the internet a few times. It could be that the frequency of the light is changed (the word “resonance” hints at this), for example by splitting a high energy photon in two lower energy photons.

    It would be nice if a link to the original source was included so that interested readers can try to decipher it themselves.

    • sternhead

      Something non-linear going on here, see the work of Bloembergen (red laser beam goes in, harmonics happen, blue comes out) and followers.

    • Hans

      I must correct myself: The Shockley-Queisser Limit is not only determined by spectral losses, recombination and some other factors are included as well. However, concentration can only slightly move the limit upwards . So my main conclusion remains: there must be something else going on as well.

  • WhatTheFlux

    Hey, if they can figure out how to run the world on wind and solar, more power to them. I’m a nuclear fan, myself, but I hope they do well with this. We need all the help we can get.

    • Bob_Wallace

      I’m going to seize on your opening to once again post my summary of what I think is a very important piece of research. It demonstrates that we could, in fact, run the world on wind and solar. If that was all we had to work with….

      There’s a very interesting study just out. The authors took on the question of whether it would be possible to run a real world grid on only wind, solar and storage and do it for a reasonable price. They found that they needed to include a tiny bit (0.1%) of natural gas to keep it affordable.

      Researchers at University of Delaware used four years of weather and electricity demand/load data in one minute blocks to determine 1) if a combination of wind, solar and storage could meet 99.9% of demand and 2) the most cost effective mix of each to meet demand.

      The data for 1999 through 2002 came from the PJM Interconnection, a large regional grid that services all or part of 13 states from New Jersey west to Illinois, from Pennsylvania south into Tennessee and North Carolina. This is the world’s largest competitive wholesale electricity market, serving 60 million customers, and it represents one-fifth of the United States’ total electric grid.

      They used currently available technology and its projected price in 2030. They included no subsidies for wind and solar in their calculation. They did not include hydro, nuclear, tidal or other possible inputs. They also did not include power sales to and purchases from adjacent grids. They used three existing storage technologies – large scale batteries, hydrogen and GIV (grid integrated vehicles).

      They found that by 2030 we could obtain 99.9% of our electricity from renewable energy/storage and the remainder 0.1% from fossil fuels for about what we currently pay “all-in” for electricity. The all-in price of electricity which includes coal and oil produced health costs currently paid via tax dollars and health insurance premiums.

      During the four year period there were five brief periods, a total of 35 hours, when renewables plus storage were insufficient to fully power the grid at an affordable price and natural gas plants came into play. These were summer days when wind supply was low and demand was high. The cheapest way to cover these ~7 hour events was to use existing natural gas plants rather than to build additional storage. Adding in hydro, tidal, etc. would further reduce this number.

      After 28 billion simulations using differing amount of wind, solar, storage and fossil fuels they found the best solution was to over-build wind and solar and at times simply “throw away” some of the produced power. Building “too much” wind and solar turns out to be cheaper than building more storage given the storage solutions we have at this time. Finding markets for the extra production, selling electricity to offset natural gas heating for example, further reduced costs.

      Budischak, Sewell, Thomson, Mach, Veron, and Kempton Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time Journal of Power Sources 225 (2013) 60-74

      https://docs.google.com/file/d/1NrBZJejkUTRYJv5YE__kBFuecdDL2pDTvKLyBjfCPr_8yR7eCTDhLGm8oEPo/edit

      Remember, this is a “worst case” study. Add in hydro, tidal, geothermal, and residual nuclear and the price drops because less storage will be needed. The same happens when there is exchange of power between grids.

      And, remember, we overbuild capacity today. We have generation that only comes into play on those very rare, very hot days when we hit peak peak demand.

      And those 2030 wind and solar prices? The authors used somewhat dated (2010) projections. Current prices have already brought the cost of wind down to their projected 2030 level and solar is already cheaper. We almost certainly will have better/cheaper storage than they used in their study.

      So, yes, we can have a renewable grid that gives us electricity when we want it. And it’s very likely that our electricity will cost less then than it does now.

      • dynamo.joe

        I don’t have a problem with any of this, except for “throw away” the excess energy. We all know that would never happen. Someone will make up a business that makes sense with an intermittent, ultra-low price electricity input.

        • http://twitter.com/aligatorhardt aligatorhardt

          One of those businesses would be hydrogen production from excessive electricity during very windy times. Hydrogen can be used as back up gas for demand leveling turbines or used for transportation fuel.

      • WhatTheFlux

        Bob – Unless I missed something, the financial success of the U. Delaware plan seems to hinge on re-directing the money we would save from lowering our externalized carbon fuel health care costs. Sorry, but…

        Re-jiggering health care dollars to even get something as wimpy as Obamacare off the ground nearly sparked a civil war. So I don’t see this plan as feasible, although on paper it looks fabulous.

        Seems to me that for an evolutionary energy system to be implemented, it would have to pay for itself within the existing paradigm and without subsidies or restructuring of existing money flows — a plant get built for X dollars that produces Y power at Z cost.

        • Bob_Wallace

          This wasn’t a study to tell us how to solve the political problems of our electricity system. It was to show us that we could and that the end result would cost no more than we are paying now. Using grown up’s accounting – being honest with ourselves about what we are really paying for the electricity we now use.

          And the study was limited. Hydro, geothermal, existing nuclear, power swaps with other grids were not included. Bringing in more generation variation along with load shifting would lower the cost. And, don’t forget, the study’s “2030 costs” are almost certainly higher than what wind and solar will cost in 2030. They are high for 2013 and we’ve got another 17 years of innovation to come.

          Also not included was the cost of replacing our coastal cities and millions of us starving to death if we don’t stop the worst of climate change.

          Switching to renewables will cause a short term spending increase. Building the railroads, the interstate highway system, the electric grid and other major undertakings cost up front money. But they all have been excellent investments which have returned their costs many times over.

          An electrical system which doesn’t wreck our environment, doesn’t harm our health and gives us cheaper electricity is something worth investing in.

        • http://twitter.com/aligatorhardt aligatorhardt

          There is no electric power system that does not get subsidies. Drop all subsidies from dirty power and wind, geothermal, hydro and solar power are the clear winners. What does the health care law have to do with the energy question? Nothing. With single payer health care, the government would have to consider the cost of pollution. Then we would see nuclear and coal power shut down fast.

    • http://twitter.com/aligatorhardt aligatorhardt

      Present technology is fully capable of delivering all needed electricity for less cost, and less harm.

      • congressive

        I have a 3.4 kw solar array on my home roof. Takes up less that a quarter of my entire roofing surface. It generates more than I can use. My meter has run backwards for two years now. My “distribution grid” is two feet long, from the inverter to the fuse box. This is a no brainer. But the liars and the special interests have poisoned the facts with garbage science. Oh well. I’m just hoping they keep raising the rates here – heck, double or triple them – ’cause that just makes my investment even better. Flame on, losers.

        • arne-nl

          +1e9. I could have written that.

          Incidentally I have a solar installation of exactly the same size and it is tremendous fun to run you own power plant. No noise, no smoke, no moving parts, no maintenance. And even without a feed-in tariff, very profitable. Thanks to the mass production kick started by Germany and Spain.

          And the best part is that the solar haters can not have the same advantage because their religion forbids it! Losers indeed.

  • http://www.facebook.com/people/Padric-OFish/100001855682804 Padric O’Fish

    > “Because the diameter of a nanowire crystal is smaller than the wavelength of the light coming from the sun it can cause resonances in the intensity of light in and around nanowires. ”

    Sounds like nonsense to me.

    • hobagman

      Maybe that’s because you’re an idiot

    • http://profiles.google.com/andrea.david.edelman Andrea David Edelman

      makes sense to me, try to force a large “something” down a small pipe you’ll increase the pressure….

    • SecularAnimist

      It’s quantum physics. So of course it sounds like nonsense. Quantum physics IS nonsense. It happens to be the most accurate description of physical reality ever conceived, but that doesn’t mean it makes sense.

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