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Power Science

Researchers Improve Solar Cell Performance 292

Vegematic writes "Researchers at MIT have improved solar collectors using dyes. They just increased their performance results by a factor of 4. These paint-on materials can increase the power obtained from existing solar cells by a factor of over 40 without needing to track the sun. 'By collecting light over their full surface and concentrating it at their edges, these devices reduce the required area of solar cells and consequently, the cost of solar power. Stacking multiple concentrators allows the optimization of solar cells at each wavelength, increasing the overall power output.' There is also a shorter FAQ available."
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Researchers Improve Solar Cell Performance

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  • Well.. (Score:3, Funny)

    by grajzor ( 1307967 ) on Friday July 11, 2008 @04:16PM (#24158261)
    Imagine that Window come crashing down... *cough*
  • by Atomm ( 945911 ) on Friday July 11, 2008 @04:17PM (#24158267) Homepage
    You know, when they post another story about the incredible discoveries in solar power that seem to never actually make it to those of us who would be interested if it was cheaper and more efficient..... Show me a company that is already selling this stuff and then I'll be interested.
    • by rumblin'rabbit ( 711865 ) on Friday July 11, 2008 @04:26PM (#24158393) Journal
      The headlines should read

      Energy Crisis Solved Third Time This Week!

      right above

      Cancer Cured Seventh Time This Year!

      • by Unending ( 1164935 ) on Friday July 11, 2008 @04:41PM (#24158563)
        the truth is the energy crisis *is* solvable, but the bureaucracy responsible doesn't have any incentive to implement the solutions.
        • by element-o.p. ( 939033 ) on Friday July 11, 2008 @05:36PM (#24159187) Homepage
          Okay, just being contrarian, but in a free-market society, what bureaucracy is responsible for implementing solutions? I thought the market would demand, and businesses would respond?

          Granted, government can do a lot to encourage the growth of a new industry, but is it really government's job to produce industries?
          • by BoberFett ( 127537 ) on Friday July 11, 2008 @05:52PM (#24159325)

            Government solutions give us things like minimum requirements of corn-based ethanol in your gasoline because: Nothing is quite as intelligent as using your food supply to haul Chinese made goods around the country.

          • by Original Replica ( 908688 ) on Friday July 11, 2008 @06:04PM (#24159415) Journal
            but in a free-market society, what bureaucracy is responsible for implementing solutions?

            That bureaucracy would be the government. Not because they want stop solar, but because they feel the need to intervene where certain crucial resources are concerned because you can't have retired Floridians that live on fixed incomes dying because they can't pay the electric bill and keep the AC running. I'm not saying that my example is a likely outcome of an unregulated power market, but it is most certainly an example that is used in making sure that the power market stays regulated. California has struggled with an unregulated power supply industry. [spur.org] All argument about the pluses and minuses of government regulation aside, the fact is that in most places electricity is a regulated utility and that serves to help contain fluctuating costs and ensure a steady supply. That government assurance lessens the attraction of being energy self sufficient, and that lessened desirability fails to counterbalance the added costs and maintainance of home solar, for most homeowners. If electricity were seen less as a city supplied utility and more of a commodity with many consumer options (like gasoline or groceries) I think that the public interest in solar would be much higher and the available solar products would be more refined.
          • by AmericanInKiev ( 453362 ) on Friday July 11, 2008 @09:29PM (#24161043) Homepage

            When government chooses winners; it can never go back to a free economy. Unfortunately, the government has been choosing winners in Energy for a long time. It is one of the areas in which we are a communistic country; and it shows, we have aging decrepit energy infrastructure - while our television/telephone/internet infrastructure is quite modern by comparison. The FCC has done a much better job of providing competition for wire services than the Energy Department has for its wire services.

            (Also, the gov. must internalize externalities - but in asking the question, you've identified yourself as probably not understanding those two words. A little econ 101 might help, as it's an important point.)

    • Re: (Score:3, Informative)

      by digitrev ( 989335 )
      Umm, if you read the FAQ, they said that they're hopeful that this improvement will be in production in three years.
      • by Anonymous Coward on Friday July 11, 2008 @04:54PM (#24158741)

        Um, if you were paying attention, there's another announcement from some company about their revolutionary increases in solar efficiency every couple of months. They're always 'hopeful' it will be in production 'in a few of years'. It never quite manages to materialize. That is what GP is bitching about (quite justifiably).

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        I read the following:

        They...hopeful...will be...years

    • by oever ( 233119 ) on Friday July 11, 2008 @04:53PM (#24158721) Homepage

      All sentences in the linked article are artfully crafted to contain snippets like 'increases power', 'decreases cost'.

      However the linked movie [mit.edu] is fairly insightful.

      What they're saying is: we absorb light in the coating. Most of then energy that's absorbed is transmitted through the glass to the frame, where it is converted into electrical energy. This idea is from the '70s, but advances in the materials used have improved the efficiency.

      Nevertheless, no word is uttered on any practical installations, nor is there any mention of the efficiency compared to the most efficient currently available system, which is very suspicious.

      If this becomes popular and oil prices go up, you better get used to living in an orange environment.
      Since this coating absors mainly non-orange, it might be possible to combine this with greenhouses. The plants get the orange light and the coating takes the rest.

      • by Khyber ( 864651 ) <techkitsune@gmail.com> on Saturday July 12, 2008 @12:37AM (#24162115) Homepage Journal

        "The plants get the orange light and the coating takes the rest."

        Most of the photosynthetic response curve is in the blue and red areas, orange is actually pretty low in the curve and thus many plants do not use that wavelength.

    • by Sockatume ( 732728 ) on Friday July 11, 2008 @04:58PM (#24158791)
      "seem to never actually make it to those of us who would be interested"

      You say that as though all of the previous breakthrough announcements have turned out to be dead ends or something. Turning basic research into a product takes years, if not decades, so it shouldn't be surprising that you're having to wait a little.
    • by QuantumRiff ( 120817 ) on Friday July 11, 2008 @05:20PM (#24159045)
      NanoSolar was all over slashdot for quite some time... (they basically print solar panels on flexible plastic). They are much cheaper than regular solar panels (although much less effecient per sq. meter, but the cost/watt is still cheap) You can now buy them. However, their production capacity for the next few years is already purchased, so you might find them from a distributor, if you know someone who knows someone..
    • Re: (Score:3, Informative)

      by ILuvRamen ( 1026668 )
      amen to that! This has got to be the 10th unique solar panel breakthrough article this year. They must be up to what like 110% efficiency by now? lol. But seriously, a 4x improvement?! This should be for sale to consumers and being built into power plants in about 3 months. I mean it's free, unlimited power FFS! And yet still nothing. Is it all the government's fault for slowing it all down? Is it patent squatters? Is it oil compant patent buyouts? Whatever it is, they should quit it so I can buy a
      • Re: (Score:3, Insightful)

        by TapeCutter ( 624760 ) *
        Two simple ways to judge TFA (that I haven't read)...

        1. A breakthrough for who/what?

        2. 4x improvement over what/when?

        I'm 50yo and from my own experience the world has definitely changed, IMHO mainly in a good way. Breakthroughs do occur, and when you take science/technology as a whole they have occured at an astonishing rate over the last half century. However even with a science degree and a lifetime of practice reading these things, unless you know something about the subject it can be difficult
    • by Idbar ( 1034346 )
      There's also something I cannot understand. So, if they concentrate light on the borders, yet, light passes through, why not stacking them until no light passes, and use all the concentrated energy at the borders.

      If there is still light crossing, isn't still a way of keep re-concentrating it using the same material?
  • Wow! (Score:2, Funny)

    by Anonymous Coward

    They should use this with the new 40% efficient solar cells. Then they'll have 160% efficiency!

  • from the FAQ (Score:5, Informative)

    by Singularitarian2048 ( 1068276 ) on Friday July 11, 2008 @04:18PM (#24158287)

    Why did LSCs fail in the 1970's? Two reasons: the collected light was absorbed before it reached the edges of the glass or plastic plates, and the dyes were unstable.

    What about stability? We tested one of our devices and found that it was stable (to 92 percent of initial performance) for three months. This isn't good enough yet for products but we are confident that the technology developed for organic light emitting devices (OLEDs) in televisions will be portable to this application.

  • So when and where can I get some of these cells in a user-installable 'shingle' form to re-roof my home's traditional shingle roof? (To be tied them into series/parallel grid cells with power controller and inverter, etc..)
    Not needing to track the sun makes them extremely suitable for my pitched roof facets... and possibly cost-effective too!
    • Re: (Score:3, Interesting)

      by KGIII ( 973947 )
      I've been watching those folks over at M.I.T. for a while now, of all the projects out there this [raw-solar.com] looks to be the more promising in the near term.
  • Then I'll be real interested.

  • by FlyingSquidStudios ( 1031284 ) on Friday July 11, 2008 @04:19PM (#24158319)
    once we reach peak solar in 2015.
  • > "...increased their performance results by a factor of 4."
    > "...increase the power obtained from existing solar cells by a factor of over 40"


    What a dirty trick to get us to RTFA. :-b

    FYI it's 40. Most impressive.
    • Re:Factor (Score:5, Informative)

      by cartman ( 18204 ) on Friday July 11, 2008 @04:33PM (#24158487)

      The quoted factor of 40 improvement is a comparison against unconcentrated solar cells, which nobody uses. At present, all the solar generating plants in the world use mirrors to concentrate the sunlight on the solar cells, thereby greatly increasing performance.

      The "factor of 4" improvement refers to how much they've improved over their previous results; it does not refer to an improvement over currently-deployed technology.

      But the question is, how much does this technology improve performance relative to currently-deployed mirror concentration? And, what is the cost relative to currently-deployed mirror concentration?

      • I think it will probably be less efficient than mirror concentrators, but the operating/maintenance costs will be much lower since there are no moving parts (they don't track the sun).

        Of course, this all depends on the magical OLED technology that will make blue OLEDs last longer! :) They seem to think that will happen in the next 3 years.

        • Re:Factor (Score:5, Informative)

          by AmericanInKiev ( 453362 ) on Friday July 11, 2008 @06:07PM (#24159445) Homepage

          Right, most of the trucks driving around in a Solar Farm aren't replacing hydraulic pistons (which operate at one cycle per day).

          The trucks are cleaning the surfaces. This technology won't require cleaning because why?

          They have achieved 40x concentration; but there is no cell currently manufactured which is cost competitive at 40 suns. If you find one - there are hundreds of ways to concentrate light to 40x.

          The reason concentrators are 1000x is because that is precisely where III-V cells are most economic.

          Also no discussion of module efficiency. This puts the tech in a class with nanotech, which are equally quiet about their efficiency.

          Indeed the disturbingly inaccurate use of the term effeciency by the author suggests a weak grasp of the subject.

          • Re: (Score:3, Informative)

            by MightyYar ( 622222 )

            In their defense, I don't think that they are claiming that this will replace the big solar farms. I think that they are envisioning this tech being used where windows currently are installed, or where solar was only worth installing with tracking collectors - so basically you get feasible solar installations where it wasn't feasible before.

            They did nothing to improve solar cells themselves, and thus the efficiency is not touched upon - these guys are just getting light to the edge of a piece of glass.

            • Re:Factor (Score:4, Insightful)

              by AmericanInKiev ( 453362 ) on Friday July 11, 2008 @09:21PM (#24160971) Homepage

              There is a glut of new and exciting ways to bounce light. We have lenses and fresnel mirrors in conical or linear; funnel mirrors, holograms, diffraction grates, and concentric funnel mirrors. (I am the very picture of a modern...)

              I think we've safely reached the point where novel can no longer be consider a useful parameter.

              What is the cost - and what is the efficiency? longevity etc ...

              At some level, we find ourselves on a Titanic, and in need of a solution to a problem with significant time and resource constraints.

              I submit that this proposal, like so many in the same camp, does more to run out the clock, than it does to advance the ball.

              EPRI has reported that Heliostats with salt storage and steam power is the least expensive means to a post-oil world. Unless this technology can demonstrate some advantage relative to the gold standard; I think its noise.

              To your point, there is no real market for neighborhood solar; and there is no social benefit for wasting tax dollars on roof-toys - or anything other than the best-of-breed solutions.

              AIK

      • Re: (Score:3, Insightful)

        by amorsen ( 7485 )

        At present, all the solar generating plants in the world use mirrors to concentrate the sunlight on the solar cells, thereby greatly increasing performance.

        Only the ones in areas with few clouds. Of course those places are best for solar anyway, but for the rest there's this new technology.

      • by Jeremi ( 14640 )

        The quoted factor of 40 improvement is a comparison against unconcentrated solar cells, which nobody uses.

        Aren't all those photovoltaic panels I see on people's rooftops unconcentrated? Or is there some non-obvious concentration method that they use, that I'm not aware of?

  • by EdIII ( 1114411 ) * on Friday July 11, 2008 @04:22PM (#24158359)

    I have heard about a ton of solar technologies in the last 24 months that are supposed to revolutionize the way we get energy.

    However, I don't see a product.

    This is an uber product. The ability to generate electricity up to 40 times the amount of existing solar while allowing as low as 10% of the light to enter?

    Commercial Buildings? This technology is off the hook. It not only generates electricity, it SAVES electricity being used to cool the building.

    I am sure this would be used on new and existing residential buildings as well. The ability to create skylights while providing power?

    I hope this one actually makes it to the market within 5 years.

    • by dpilot ( 134227 )

      Hopefully one of these many solar power improvements will make it to market some time before fusion power.

    • I think it's fair to say that if it's coming out of a university lab, it's not a "product" (uber or otherwise) yet. It's front-line science, not the new iPod With Bacon.
      • by EdIII ( 1114411 ) *

        Yeah, I meant to say the potential to become an uber product. Should of previewed that a little bit more.

        That's why ./ should allow edits in the future. You would be able to see what posts were edited and how of course. Otherwise I just have to keep being a moron who clicks submit too fast.

    • by maxume ( 22995 ) on Friday July 11, 2008 @05:06PM (#24158873)

      It is pretty likely there will be an inflection point. At the moment, my take is that the subsidized pay off period is still pushing 20 years, so solar is pretty much only any good if you are rich and don't like it when your power goes away, or if you want to live really far from the grid. When the unsubsidized payback hits 10 years, Joe-dumbass is going to be screwing up an installation on his garage, driving the payback time even lower.

      Up until the inflection point, nothing will seem to make a difference. Afterwords, it will be like "what took so long and where did all those things come from".

      • by Damvan ( 824570 )
        You might want to crunch your numbers again. I am not going to bore you with all the exact numbers, but I installed my 3.2 kw system in 2004, and my calculated payback based on the numbers obtained with 4 years of actual use will be a little over 8 years. It was a subsidized installation though, with rebates paying more than half the cost. But the costs of the equipment are lower now, and there are higher rebates available than what was available 4 years ago. Granted we aren't reaching your unsubsidized
    • This is an uber product. The ability to generate electricity up to 40 times the amount of existing solar while allowing as low as 10% of the light to enter?

      Given that current solar cells are 20-40% efficient, I'm guessing the "40x" statistic is, um, bullshit.

      I also question the "we don't have to track the sun" part. If you want maximum efficiency, you do have to track it. At an oblique angle, you have less energy hitting the surface, and hence less power generated.

      • by Areyoukiddingme ( 1289470 ) on Friday July 11, 2008 @07:12PM (#24160001)

        Well no, the angle doesn't change the amount of energy hitting the panel. What it changes is how well the semiconductor solar cells can convert that energy. You don't have to track with these panels because the organic film absorbs, then re-emits the light, and due to the nature of the molecules, it always re-emits the light in the same direction, regardless of the incoming angle. The classic semiconductor solar cells themselves, attached all the way around the edges, are the devices that are sensitive about angle. They receive light at their optimal angle always, emitted from the organic film on the plates, rather than directly from the sunlight.

        You lose efficiency in the absorption and re-emission process, but that loss is apparently worth the cost of admission, if these guys have done their math right. Being from MIT, we can hope they can do math.

        This technique has a whole host of advantages over classic off-the-shelf panels you can buy today, which the article didn't go into.

        The panels you can buy today are very sensitive to shadows. Each cell produces only so much voltage. To get a useful voltage out of them, you have to wire them up in series. If some percentage (50%) of a row is shadowed, the panel will actually effectively shut itself down, and produce no power at all, because of the non-participating cells. (The shutdown is accomplished with passive circuitry, not some sort of machine or processor.) This means that in a typical residential situation, you can't have so much as a chimney on your roof, or your panels could become very expensive powerless decorations. You certainly can't have any trees that could even partially shade your roof. This concept eliminates that problem. The organic molecules in question are very egalitarian about how they re-emit what they absorb. It gets spread out evenly, all the way around. This means that if any portion of the panel is shaded, all of the semiconductor cells still get a lot of (concentrated) light, and it takes a lot more shadow to shut them down.

        Another issue with modern panels is the fact that a classic semiconductor solar cell is useful only through a very narrow band of wavelengths. Sunlight is very broad band light. (No jokes about bitrates, thank you.) It shows up at your roof in all kinds of frequencies. The panels you can buy today ignore a large fraction of those frequencies, since they only work at what they're tuned for. However, in the process of ignoring the other frequencies, your standard cell also blocks them entirely. So even though you can manufacture semiconductor cells with different bandgaps that will absorb different sunlight frequencies, you can't stack them directly on top of each other and gain anything. The uppermost in the stack shadows all those beneath, so they're pointless. An older slashdot story about how to manufacture a multi-bandgap semiconductor cell was posted a while ago, but that's still in early research stages too, and it apparently involves fairly difficult semiconductor manufacturing techniques. These panels do an end-run around that problem. Different dye coatings absorb different frequencies of sunlight and DON'T block the remaining frequencies. They pass through. So you can stack concentrator panels, up to some limit, and each one has semiconductor solar cells around the edges specially tuned to utilize the light frequency the dye emits. This is the big win, and the cause for the whopping efficiency claims. The transmissiveness of these concentrators for frequencies they're not tuned for means you can make a sandwich out of them and the resulting panel can use many more frequencies out of the same square meter. There's probably still some limit to how many layers you can stack before you're wasting your efforts, but it's enough to be worth the trouble.

        Lastly, classic semiconductor cells can be manufactured specifically to operate efficiently in concentrated light vs standard out-of-the-sky sunlight. That's the reason for the Fresnel lens panels that have

        • Re: (Score:3, Informative)

          by instarx ( 615765 )

          Well no, the angle doesn't change the amount of energy hitting the panel.

          Not true. One square foot of light hitting a surface perpendicularly imparts its energy to one square foot of surface. If you increase the angle of incidence the square foot of light spreads its energy out over a larger area and the original square foot of surface area now receives much less energy. It's the reason we have seasons.

          You had a very long post, but after that first sentence I didn't bother to read the rest of it - I guess first impressions ARE important.

  • Pure dark (Score:5, Funny)

    by Dan East ( 318230 ) on Friday July 11, 2008 @04:23PM (#24158367) Journal

    If solar cell efficiency actually increased a mere 1% for each story slashdot has posted regarding solar cell improvement, then panels would be generating electricity in complete darkness by now.

  • by Necreia ( 954727 ) on Friday July 11, 2008 @04:27PM (#24158405)
    For those that didn't RTFA (aka, almost everyone)

    The focus of the article is on how this could work in place of a regular window// not just as something to amplify solar cells. Since it can push the light to the edges, only the rim has to be fitted with collectors.

    Pretty cool
  • 4 vs 40. (Score:4, Informative)

    by BigGar' ( 411008 ) on Friday July 11, 2008 @04:28PM (#24158423) Homepage

    FYi, its 40 time better than standard solar cells and 4 times better than their previous results.

    The reference from the FAQ
    1. Currie, M. J., Mapel, J. K., Heidel, T. D., Goffri, S. & Baldo, M. A. High-efficiency Organic Solar Concentrators for Photovoltaics. Science. In Press.

    • OK, so a standard solar cell is 15% efficient. So this one is (.15*40) = 600% efficient? And their previous results were 1/4 of that, or 150% efficient? Dayyyumm!
      • Re: (Score:3, Informative)

        by MightyYar ( 622222 )

        Actually, yes... but they are collecting more sunlight for each cell, not making the cells more efficient :)

        The concept is not new, but apparently the dies are better and more stable now.

      • Maybe in terms of how many actual solar cells are used then yes. The greater then 100% efficiency comes from the use of collectors. The cells themselves are not greater then 100$ efficient. It's just that the collectors amplify the light getting to them allowing that many times greater output.
  • by edwebdev ( 1304531 ) on Friday July 11, 2008 @04:43PM (#24158603)
    Here is a link to the actual paper published by the MIT team:
    http://www.sciencemag.org/cgi/content/short/321/5886/226 [sciencemag.org]
    • We report single- and tandem-waveguide organic solar concentrators with quantum efficiencies exceeding 50% and projected power conversion efficiencies as high as 6.8%.

      So when photovoltaics say they're 35% efficient, does that mean power conversion efficiency? Or is it this quantum efficiency, which seems somehow less relevant than, you know, the amount of power that the cell can produce?

  • And at least hit break even in, say, 5 years (with the interest on the loan factored in)?
  • Expensive stuff (Score:3, Informative)

    by jmichaelg ( 148257 ) on Friday July 11, 2008 @04:47PM (#24158647) Journal

    This article [venturebeat.com] says the window treatment for the dye alone would run around $300-$400 per square meter of glass. The solar cells would cost extra. The process requires vapor deposition which adds to the cost and it alters the light color passing through the window which may or may not be acceptable to the end user. And then there's this:

    Oddly enough, a number of reports appearing today (for example, in the Associated Press) suggested that Covalent's concentrators would be of use in actual windows, but cofounder John Mapel made no mention of that possibility when we talked last week. That's no great surprise -- it would be difficult to get high-intensity light into vertically-positioned windows, much less windows placed on the wrong side of a building.

    As a number of other posters have pointed out - wait for an actual product to see what it actually is and what it's capable of.

  • I love these types of breakthroughs, but when is something actually going to happen in the real world with this stuff?!

    Off oil as quick as possible!
  • I mean, come, on, if some schmoo has a vapo solar panel and can get himself slashdotted, maybe I ought to start selling fusion reactors, ready for delivery, "real soon now", just to get the clicks!

  • Don't spread the word, or GM/Exxon/etc will buy all the patents again like how flywheel cars keep disappearing.

    • by geekoid ( 135745 )

      Yes, it's the patents that keep flywheels from becoming commercially viable. Certianly not the myriad of issue that they have.
      Starting with ahve a huge spinning object flying during an Auto crash.

      Patents aren't magic you know. Someone else could release the plans, especially in the era if World Wide information distribution.

  • by anon37 ( 522694 ) on Friday July 11, 2008 @05:09PM (#24158905)
    This won't work for the same reason that interior paint won't last on the outside of your house. Interior paints use organic dyes, just like this MIT concentrator. To the great frustration of the paint industry, organic dyes just do not last in sunlight: the molecules breakdown.

    Similar solar concentrator concepts have been looked for three decades (look up, for example, Prof. Reisfeld's work at Hebrew University) and have not yet made it out of the lab.
    • by geekoid ( 135745 )

      True, but there have been many improvements since then, and it's nice to ahve more people looking at the same problem, especially if it's to solve it for different reasons.

      I certianly would go running out and investing my meager amount of money into it.

    • That sure would be a downer if these solar concentrators were destroyed by solar radiation. Watch out if the warranty is only 90 days!
  • by heroine ( 1220 ) on Friday July 11, 2008 @05:28PM (#24159113) Homepage

    With all the solar cell breakthroughs since 2005, we should be up to 10,000% efficiency by now.

  • by WillAffleckUW ( 858324 ) on Friday July 11, 2008 @05:51PM (#24159311) Homepage Journal

    While it's great that we have an improved solar cell film, the reality is that, for the most part, the most efficient method used on a practical worldwide scale involves passive solar heating, especially for providing heating and hot water.

    Part of the problem is that the manufacturing process - such as that used by Sony in cranking out OLEDs (which they build at the same plant as their photovoltaic solar cells) - causes a fair bit of pollution, both thru film extrusion, bonding, and the doping process.

    By 2020 we may see some useful scaled implementation of photovoltaics, but it's still projected that the vast and overwhelming majority of growth in solar will be it's use in passive solar heating (and cooling, using heat exchangers) and in passive solar water heaters, as both such uses have little in the way of pollution in the manufacturing process and have an easier permitting process for factories, installation, and residential and commercial use, and easier to develop tax incentives for on the local and national scales worldwide.

  • This reminds me of those plastic, colored transparent clipboards you used to see - they would trap the light internally and it looked like they were glowing around the edges. Sounds like the same technology, ramped up. So if it never pans out for solar cells, these guys could still be positioned to make a killing in the novelty clipboard market! Where do I invest?

  • Solar cells undergo degradation with light exposure. The degradation is usually proportional to the number of photons incident on the cell. Does this method *shorten* the effective lifetimes of existing solar cells by a factor of 40? Are there cells that exist that this solution is practical for? Do the gains outweigh the costs if I use this system to "upgrade" my solar cell array and end up slashing the array's lifetime by a factor of 40?
  • So let me see, current cells have 15% efficiency or so , the best stuff ( I.e GaAs ) can reach 30% - 40% , and this tech will increase output power by more than an order of magnitude, meaning they should output at least 150% of the energy they receive?

    If the numbers are to add up then what they are doing is a concentrating solar power plant and it should be compared to the values for such instalations. Heck, using their way to do the counting I could design a power plant which outputs 100 times the power of

  • by John Sokol ( 109591 ) on Friday July 11, 2008 @09:14PM (#24160913) Homepage Journal

    A. Goetzberger et al., "Solar Energy Conversion with Fluorescent Collectors", Applied Physics 14, 1977, pp. 123-139.

    Yes 1977!!!

    I was also playing with this using plastic from TAP plastics (in the SF Bay Area) http://www.tapplastics.com/ [tapplastics.com] in the late 80's.
    Works ok.

    See:
    Patent 4149902
    Patent 5227773
    Patent 5816238
    Patent 7316497

    Mobay Chemical Corporation make a fluorescent called LISA. "fluorescent dye-doped edge-illuminating emitter panels" Technically.

    There were some articles.
    "A Little Light Goes a Long Way with Lisa", Mobay Corp. Marketing Document.

    "Light-Collecting Plastics-A Brilliant Idea", Provisional Information Sheet, Mobay Corp.

    Steven Ashley, "Razzle-Dazzle Plastic", Popular Science, pp. 100-101. Sorry can't find the year, (any one can you help here)

  • Nit pick time... (Score:3, Informative)

    by farnsaw ( 252018 ) on Saturday July 12, 2008 @04:41AM (#24162991) Homepage

    I know we will all nit pick this to death so here is mine...

    From the FAQ:

    "The sun is an inexhaustible source of clean power."

    Well, not quite. I know that we cannot exhaust it just by using it's normal emissions as we would place no additional drain on the sun's resources by using solar power than if we didn't exist, however, the suns normal processes will eventual exhaust even it's vast resources of Hydrogen and then start "burning" (there you go, nit pick me now) hydrogen which will drastically change its characteristics. I do however agree that we (everyone alive today and probably the human race in general) won't really care by that time because, hopefully, everyone alive today will be long dead by then and, again hopefully, the human race will have moved on to the rest of the galaxy (galaxies?) by then and look back at "the birth place of mankind" with fond memories but the loss of the Earth due to the sun running out of Hydrogen will be a fairly minor news item.

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