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Plasmonic Nanostructures Could Prove a Boon To Solar Cell Technology

Posted by samzenpus on from the brighter-and-brighter dept.

Zothecula writes "Researchers at the University of Pennsylvania have found a way to harvest energy from sunlight more efficiently, with the help of so-called plasmonic nanostructures. The new findings suggest that plasmonic components can enhance and direct optical scattering, creating a mechanism that is more efficient than the photoexcitation that drives solar cells. The development could therefore provide a real boost to solar cell efficiency and lead to faster optical communication."

23 of 107 comments (clear)

  1. Plasmonic nanostructures by NoNonAlphaCharsHere · · Score: 4, Funny

    Someone's been spending too much time reading "The Big Book of Star Trek Technobabble".

    1. Re:Plasmonic nanostructures by SJHillman · · Score: 4, Funny

      Nonsense. The summary doesn't once mention tachyons OR reversing polarity.

    2. Re:Plasmonic nanostructures by mcgrew · · Score: 3, Informative

      But that's not all the article said; it isn't just more surface area, but with plasmonics tuned so that electrical resistance is lower and the maximum number of electrons can get knocked loose by a photon.

      Don't expect a physics class in a magazine article, but for someone not in the field wikipedia will do. I looked up plasmonics before reading the article and it made the article a lot more informative.

      --
      Free Martian Whores!
  2. This has got to be the 37th amazing improvement by fredrated · · Score: 2, Interesting

    to solar technology. Call me when one of these finally hits the shelves.

    1. Re:This has got to be the 37th amazing improvement by timeOday · · Score: 3, Informative

      They do, all the time. Why do you think the cost of solar has decreased by 90% over the last 30 years?

    2. Re:This has got to be the 37th amazing improvement by Bender_ · · Score: 2

      >They do, all the time.

      In fact, they never do at all! If you look at the market statistics, you will notice that >80% of the market is crystalline silicon. And while there are different ways to manufacture crystalline silicon solar cells, companies have been extremely reluctant to introduce new technologies. In fact, almost all solar cells today are still made with the same manufacturing process steps as 10 years ago. Conversion efficiencies have improved simply by tweaking these process steps.

      >Why do you think the cost of solar has decreased by 90% over the last 30 years?

      I know why the cost has decreased
      - Manufacturing cost reduction by scaling effects
      - Very significant cost reduction in raw materials
      - Reduction of material consumption by process optimization
      - And to a smaller part, improvement of conversion efficiencies by process optimization.

      News about surface plasmonic effects, black silicon and the like are surface every other weak. However they have not inched any closer to production than they were 5 years ago.

      Photovoltaic modules are a commodity. The technology and science behind it is of limited depth and not comparable to the semiconductor industry. Look elsewhere if you want to innovate in technology.

      What is needed is innovation on the system level, products and marketing.
       

    3. Re:This has got to be the 37th amazing improvement by timeOday · · Score: 2, Insightful
      For how many decades did it seem like hard drives and CRT displays would never be displaced? They just kept steadily improving the whole time, and no fundamentally different technologies could overtake them - until they did. (Hard drives decreased $/byte by increasing the denominator, whereas PV cells decreased $/watt by decreasing the numerator, does that somehow not count?)

      Sure, the vast majority of research comes to nothing. The exceptions are what make it possible for 7 billion people to exist on earth.

  3. I will believe it when I can buy it by Amadodd · · Score: 4, Insightful

    If I had a dollar for every time a uni came up with a new solar cell. The reality is that most of what you can buy is stil monocrystalline silicone, same as 50 years ago. Why is nothing commercialised?

    --
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    1. Re:I will believe it when I can buy it by Anonymous Coward · · Score: 4, Interesting

      Big Oil keeps nipping every new development in the bud before it can be commercialized.

    2. Re:I will believe it when I can buy it by rahvin112 · · Score: 5, Informative

      Every one of the inventions is being pulled forward. It is clear you have no idea what's available out there. Thin film is beginning to dominate commercial installation, in fact it's so much better that it's very difficult to even purchase thin films any more because all the production is allocated to commercial installations. Other techniques are out there and being used, the better the cell the more likely it'll be relegated to commercial installation. Most of what's available for retail purchase is the output of older cell lines that are no longer competitive on the commercial side.

      Solar is now significantly below $1 a watt and is approaching the point where in commercial installations it's amortized cost is approaching that of coal power. It's already cheaper than nuclear on all fronts.

    3. Re:I will believe it when I can buy it by rasmusbr · · Score: 2

      Because it turns out you can get more bang for your buck by improving the manufacturing of silicon cells than you can get by launching the alternatives that have been tried so far. Monocrystalline silicone is still king when it comes to conversion efficiency and they're no longer particularly expensive, so way go for second or third best?

    4. Re:I will believe it when I can buy it by rwise2112 · · Score: 2

      If I had a dollar for every time a uni came up with a new solar cell. The reality is that most of what you can buy is stil monocrystalline silicone, same as 50 years ago. Why is nothing commercialised?

      I think could be related to the types of discoveries. Discovery X gives a 10% increase in efficiency, then discovery Y gives a 8% increase, however discovery X is not compatible with discovery Y, so they both can't be used together. Also discovery X will cost 10x as much as discovery Y, so we'll have to go with Y.

      I suspect there's a lot of that going on.

      --

      "For every expert, there is an equal and opposite expert"
    5. Re:I will believe it when I can buy it by mlts · · Score: 2

      I've seen some panels that use monocrystalline silicon, then areas of polycrystalline because one is better for sun, one for shade. I've also been seeing polycrystalline panels getting about as much efficiency as the single crystals.

      It takes a bit for stuff to go from lab to market. Part of it is testing because solar installations are usually thought of as very long term investments, amortized in the terms of 5, 10, or 20 year increments. So, solar makers tend to be fairly conservative on what they put out.

      The solar industry also went through a big shakedown, so they are playing cards close to their chest for fear that their R&D will just end up a target for foreign intruders and wind up on panels being fabbed overseas for pennies on the dollar. With the fact that new R&D doesn't pay off much, at best, we see only incremental improvements in the field.

      Where we are seeing improvements are solar charge controllers. MPPT controllers that can use a voltage greater than what the batteries need are almost as cheap as PWM controllers that lop off and don't use anything over what they don't need.

    6. Re:I will believe it when I can buy it by theIsovist · · Score: 3, Interesting

      "But at a solar/green event I went to, I use so little electricity that only after mentioning that was it *maybe* worthwhile for me."

      This is a very good point. Homes, individually, don't take too much power, so powering each one of them with it's own generator (solar or otherwise) is redundant and expensive. Maintenance, too, is a pain for the average home owner. So centralizing power generation is great, for the most part. At least until you start factoring in transmission loss. What ideally will happen, and this will take time thanks to the cooperation it requires, is that district power plants will spring up. That a commercial building can produce so much power that it can sell the rest to local houses. You're starting to see this happen, and in the future, hopefully it will happen more. There's other benefits to this approach as well. Say, for instance, you run a massive server farm. This farm produces a lot of heat, and if you can capture this heat, you could use it to power your building and perhaps other neighboring buildings as well. It's an idea that's catching on in Europe and a few places in the US. So maybe solar power on your home isn't going to become viable, but that doesn't mean solar won't be in your future.

  4. Solar cells are already cheap enough by msevior · · Score: 4, Interesting

    While this all great Science, actually solar panels are already cheap enough in many parts of the world. Certainly they are in Australia since we have no tariffs on imported Chinese panels. What is really needed for greater market penetration is cheap storage. It would be great to have a around ~20 KWHr of storage for ~$2000 - $4000. Said storage needs to be stable over around 7000 cycles (20 years of operation) and provide of the order of 4 KW of power on demand. With this in place residential PV systems could provide over 20% of demand in many parts of the world.

    1. Re:Solar cells are already cheap enough by SJHillman · · Score: 4, Insightful

      I can think of a few reasons:
      1) This doesn't scale. If we want solar to catch on a massive scale, we need a way to either store it, or a way for a night/cloudy/rainy power source to fill in the gaps
      2) A lot of places where solar would be really useful doesn't have grid access to begin with. Many third world areas (IE: large portions of Africa) come to mind, but there's plenty of other places - the US has large swaths of nothingness that could benefit from solar power but don't have grid connections.
      3) Portable applications, in which in would be impractical to run a temporary grid connection to it, would do great with some energy storage.

    2. Re:Solar cells are already cheap enough by gstoddart · · Score: 2

      Why would you need storage?

      Except if we had good storage, we could be completely separated from the grid instead of relying on being able to offload energy we can't use only to have to buy it back later.

      --
      Lost at C:>. Found at C.
    3. Re:Solar cells are already cheap enough by h4rr4r · · Score: 2

      You can drop the oil from that, outside of Hawaii we don't use it for power. Solar thermal can deal with days without light. So install solar thermal along with solar photovoltaic.

      The perfect is the enemy of the good, and you are pushing for perfect. When you demand magic storage you are ensuring no solar is rolled out and that we will have to burn fuel all the time.

    4. Re:Solar cells are already cheap enough by gstoddart · · Score: 2

      Or if you have no interest in being connected to the grid and beholden to the power company which can decide to change the rates.

      Cottages, remote locations, the developing world ... these are all places where there may not be a grid, or where it may not be practical to connect to it.

      Why should you even need to involve the utility in this if what you're looking for is a 100% off-grid solution? They're just middlemen and don't bring anything to the table except a place to store your energy ... if you could do that on your own, you could basically be self sufficient.

      --
      Lost at C:>. Found at C.
    5. Re:Solar cells are already cheap enough by SJHillman · · Score: 3, Insightful

      1. The idea is to reduce non-renewable sources in favor of renewable sources. The biggest issue facing this in the long run is the need to store the energy as most non-renewable sources are not continuously reliable (wind) or are cyclic (solar, some hydro). Saying you can load balance with a non-renewable resource is a short term solution.

      2. Solar is getting pretty cheap, and a lot of places are using it to some degree already. It's not unheard of for poor African villages to use solar to recharge car batteries each day. It's the storage that's the weak link in cases like these moreso than the solar generation.

      3. Generators get expensive fast once you consider the indirect costs such as transportation. Also, see 1. Most solutions not involving some kind of energy storage are short term solutions (within the lifetime of people already born).

    6. Re:Solar cells are already cheap enough by SJHillman · · Score: 2

      "If you want to live in the woods, why would you want power?"

      If you want to live in the city, why would you want fresh food?
      If you want to live in the desert, why would you want water?
      If you want to live on a boat, why would you want to stay dry?

      I nominate that for the worst argument of the week... and Slashdot has some pretty bad arguments.

      I know a guy who lives in the Adirondacks where there are no power lines. He is completely off the grid thanks to solar and wind and a whole bunch of batteries, even in the winter when solar and wind are horrible choices. Satellite allows him to stay completely connected and still live where he wants.

      Or we can look at the big blackout a decade ago... or the ice storms every winter... if we weren't on the grid, we could just walk to our neighbors or even run an extension cord to them if our power was down. But with the grid, sometimes our best option is to go completely without power.

      It's the difference between trains and cars. Trains are great for population centers, but they quickly become inefficient, expensive, unreliable and inflexible when you try to use them for everyone's personal transportation everywhere. The grid vs personal power is the same way. And if you think everyone should live in the city, then I guess you must *really* hate food.

    7. Re:Solar cells are already cheap enough by h4rr4r · · Score: 2

      What an articulate comment. Do you have any other such wisdom to share? Perhaps you can even find a new swear word to try out on us.

      By the way, I was not saying the commenter was a nutbag, just the folks who want to live without being reliant on anyone else. It is impossible, unless they can also fab their own solar panels and practice surgery on themselves.

  5. How to make cheap solar power from gold? by presidenteloco · · Score: 2

    Isn't gold a little bit, um, expensive?

    Could these gold nano-whatchamacallits be done for a grand total of less than $1 a watt which is about the current price of PV?

    --

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