Follow Slashdot stories on Twitter

 


Forgot your password?
Close
typodupeerror
×

Nanopillar Solar May Cost 10x Less Than Silicon 199

Posted by ScuttleMonkey from the hot-off-the-presses dept.
Al writes "A team of researchers from the University of California, Berkeley, have developed a new kind of flexible solar cell that could be far cheaper to make than conventional silicon photovoltaics. The cells consist of an array of 500-nanometer-high cadmium sulfide pillars printed on top of an aluminum foil — the material surrounding the pillars absorbs light and releases electrons, while the pillars themselves transport the electrons to an electrical circuit. The closely packed pillars trap light between them, helping the surrounding material absorb more. This means the electrons also have a very short distance to travel through the pillars, so there are fewer chances of their getting trapped at defects and its possible to use low-quality, less expensive materials. '"You won't know the cost until you do this using a roll-to-roll process," says lead researchers Ali Javey. "But if you can do it, the cost could be 10 times less than what's used to make [crystalline] silicon panels."'"
This discussion has been archived. No new comments can be posted.

Nanopillar Solar May Cost 10x Less Than Silicon More

Nanopillar Solar May Cost 10x Less Than Silicon

Comments Filter:

  • That title makes me cringe. (Score:4, Insightful)

    by albedoa ( 1529275 ) on Monday July 06, 2009 @12:58PM (#28596167)
    "10x Less"? Is that like "twice as cold"?

    • Doubly Affirmative.

    • Same here. The person should have said it could cost 1/10 as using current technology. Assuming current cost is for this example $1.00 per unit. The current expression would be 100/100 (when expressed in cents). Anything compared to that can be expressed as a fraction. If they can produce it for 90 cents then you can express it as 90/100 or 9/10. The way he phrased it sound like they will give you 10x the cost to make the product.

      I see this all of the time and I keep trying to correct people, but, th

    • Re:That title makes me cringe. (Score:4, Interesting)

      by ScentCone ( 795499 ) on Monday July 06, 2009 @01:51PM (#28596997)
      Maddening, isn't it?

      The only way "ten times less" makes any sense is when you're talking about three costs.

      A is expensive! B is much more efficient, and costs half as much. C is even more efficient than B - ten times less expensive than A, compared to B.

      Otherwise, when you only have two things to compare to one another, just say that "B is one tenth the cost of A."

      Why is this so damn hard for people to process? If they could just think about it, they'd save me ten times the typing.

      • Re: (Score:2, Informative)

        by SlashDotDotDot ( 1356809 )

        "10x Less"? Is that like "twice as cold"

        Maddening, isn't it?

        I like to nitpick as much as the next guy, but I didn't blink at that title. A survey of readers would find that everyone one of them knew what the author meant. Consider it as shorthand for "Nanopillar Solar May Cost Less Than Silicon By A Factor Of 10"

        • Re: (Score:2)

          by icebike ( 68054 )

          > but I didn't blink at that title.

          Thats because your thinking process is so horribly compromised by those who don't think at all that you are starting to understand them just as parents understand baby gibberish.

          Correct this unfortunate nonsense everywhere you see it. Its not just technical shorthand, its fundamentally wrong.

      • Re: (Score:2, Troll)

        by relguj9 ( 1313593 )
        If I was buying a car or signing some contract I'd worry about shit like that......

        If you had trouble with the title though, here's some help... "less" is some constant variable representing the "new cost" that when multiplied by 10 equals the "old cost".

        silicon.cost = 10 * lesser.nanopillar.cost
      • Along these lines another one that drives me nuts is something like "The older technology uses 150% more material" when they really mean "50% more material". If they want to say 150%, they should say "150% as much material" or "1.5 times the material" (but not "1.5 times more material").

      • Re: (Score:2)

        by Twinbee ( 767046 )

        I was err.. 'guilty' of this myself once (in an old /. post, I said something was ten times lighter - as in weight).

        I don't see much of a problem at all. 10 times slower = 0.1 times as fast. 10 times lighter = 0.1 times as heavy etc. etc. It's pretty intuitive.

      • Re: (Score:2)

        by Atario ( 673917 )

        A is expensive! B is much more efficient, and costs half as much. C is even more efficient than B - ten times less expensive than A, compared to B.

        I'm having trouble processing what that means -- are you saying that C costs 1/20 what A does? Or 1/10?

        Furthermore, none of that makes sense unless you accept the concept of "N times less" as stated in the headline in the first place.

        I really don't see the problem, in fact. If "N times more" is acceptable, then surely "N times less" must be, too.

    • Re: (Score:2)

      by euxneks ( 516538 )

      "10x Less"? Is that like "twice as cold"?

      Couldn't it reasonably be assumed he's saying "a factor of ten less" i.e. {current_cost}*0.1 ?

    • Re: (Score:2, Insightful)

      by donut1005 ( 982510 )
      Same difference.

      (Which is a phrase I never understood. If two things are different in the same way, aren't they not different but instead similar?)

      • Re: (Score:3, Interesting)

        by HTH NE1 ( 675604 )

        Same difference.

        (Which is a phrase I never understood. If two things are different in the same way, aren't they not different but instead similar?)

        It's an oxymoron pun (often shortened to "same diff"), derived from "same thing". It's generally understood to mean "any differences are inconsequential", applying a loosening to the meaning of "same". See also: "agree to disagree".

      • What is 5 - 2? What is 132 - 129?

        In both cases, the differences are the same: 3.

    • Re: (Score:3, Informative)

      by dontmakemethink ( 1186169 )

      Even better is how the cells "create electrons". All we need now are cells to create protons and neutrons, and solar powered replicators will be on the market in no time!

      (TFA reads "creates free electrons", also a misnomer, should read "frees electrons")

    • Is cost represented on a linear scale? What does cost really represent? Would the cost vary by nation of manufacture? What point in time was the cost estimation created?

      Maybe a more accurate title would be:
      As of the writing of this article, the monetary manufacturing cost in the US, including labor and materials, of Nanopillar Solar may be lower by a factor of 10 than that of current Silicon based solar technologies.

      Too bad the title line is only 50 characters. And I still made a lot of assumptio

  • Great news! (Score:2, Insightful)

    by mc1138 ( 718275 )
    Another major breakthrough for solar power. Especially if they can mass produce it, but even if not, I'm sure this sort of thing will just lead to further developments down the line. In addition to making it easier for a home user to purchase and have installed, think of a reduced cost for mass deployments either in power plants, or in space exploration uses such as on a permanent moon base.

    • Re:Great news! (Score:5, Interesting)

      by dogolopee ( 886299 ) on Monday July 06, 2009 @01:19PM (#28596533)
      Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.

      • Re:Great news! (Score:4, Funny)

        by DoofusOfDeath ( 636671 ) on Monday July 06, 2009 @01:25PM (#28596605)

        Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.

        Perhaps, but is that technology "green"?

        • Re: (Score:2, Insightful)

          by NJRoadfan ( 1254248 )
          Yes, I think they call them trees these days.

        • Re:Great news! (Score:5, Interesting)

          by Rei ( 128717 ) on Monday July 06, 2009 @01:50PM (#28596983) Homepage

          Not [wikipedia.org] really [wikipedia.org], surprisingly [ecogeek.org].

          Growing plants for fuel is far, far more destructive and less efficient than just turning the solar energy directly to electricity and operating off of that.

        • To be precise, In autumn, a part of it turns red and yellow, but basically, the answer is "yes".

      • Re:Great news! (Score:5, Funny)

        by jollyreaper ( 513215 ) on Monday July 06, 2009 @01:55PM (#28597053)

        Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.

        But then we'd have these "pillars" all over the place and would not be able to see the forest for them.

    • Re:Great news! (Score:4, Informative)

      by JustinOpinion ( 1246824 ) on Monday July 06, 2009 @01:48PM (#28596937)
      For those with access, here's the actual paper:
      Fan, Zhiyong, Haleh Razavi, Jae-won Do, Aimee Moriwaki, Onur Ergen, Yu-Lun Chueh, Paul W. Leu, et al. "Three-dimensional nanopillar-array photovoltaics on low-cost and flexible substrates [nature.com]." Nature Materials advanced online publication (July 5, 2009). http://dx.doi.org/10.1038/nmat2493 [doi.org].

      One of the cool things is that this new process results in a flexible photovoltaic. In the paper they show that efficiency is maintained even after repeated bending of the material. Even if the energy collection efficiency is lower than conventional silicon photovoltaics, there are tons of applications for flexible photovoltaics, like having tents coated in the material (both for things like camping, but could also be hugely useful for the military, for temporary tents for disaster relief, and so on...), clothing that generates power, and so on... (Maybe even fanciful things like kites that collect solar and wind power?)

      It's not a commercial device yet (and oftentimes these kinds of lab devices just don't scale to mass production that well), but it's an encouraging step towards more robust solar cells, which would aid in the more widespread deployments of solar energy.

      • Re: (Score:3, Interesting)

        by vlm ( 69642 )

        No access here. I'm guessing the "pillars" are little quarter wave antennas, with a diode at the base, vaguely like a crystal radio but operating at light wavelengths instead of radio? A really old idea that has never been built (until now?)

        In that case, why are the pillars so long? 500 nm quarter wavelength pillars work best with an optimum wavelength of 2000 nm.

        Now, 2000 nm is way off in the invisible infrared.

        http://en.wikipedia.org/wiki/Visible_spectrum [wikipedia.org]

        I'm guessing in true journalist fashion, they re

        • Re: (Score:2)

          by Dravik ( 699631 )
          500nm would put them around blue-cyan as full wavelength antennas as well.

        • Re:Great news! (Score:5, Informative)

          by JustinOpinion ( 1246824 ) on Monday July 06, 2009 @02:48PM (#28597835)
          I don't think the pillars are acting as antennas in the way you're thinking. It's simpler than that. The pillars are just providing a higher surface area of interface between the light-absorbing material and the conducting material, and creating a shorter path for the electron-hole-pairs (EHP) to reach their respective conducting materials. Basically one of the main limitations in photovoltaics of this type is the short lifetime of the EHP before it recombines... having the pillars penetrate into the absorbing layers means the EHP have a shorter path to travel. From the paper:

          Conventional thin-film photovoltaics rely on the optical generation and separation of electron-hole pairs (EHPs) with an internal electric field, as shown in Fig. 1a. Among different factors, the absorption efficiency of the material and the minority carrier lifetime often determine the energy conversion efficiency15. In this regard, simulation studies have previously shown the advantages of three-dimensional (3D) cell structures, such as those using coaxially doped vertical nanopillar arrays, in improving the photocarrier separation and collection by orthogonalizing the direction of light absorption and EHPs separation (Fig. 1b)16.

          Later in the paper they discuss the light-absorbing properties of these kinds of pillar arrays:

          In addition, 3D nanopillar or nanowire arrays, similar to the ones used in this work, have been demonstrated in the past to exhibit unique optical absorption properties13,18. Similarly, we have observed reduced reflectivity from CdS nanopillar arrays especially when the inter-pillar distance is small (see Supplementary Fig. S6). This observation suggests that 3D nanopillar-based cell modules can potentially improve the light absorption while enhancing the carrier collection.

          References 13,18 are:
          L. Tsakalakos, J. Balch, J. Fronheiser, B. A. Korevaar, O. Sulima and J. Rand "Silicon nanowire solar cells [aip.org]". Appl. Phys. Lett. 91, 233117 (2007). doi 10.1063/1.2821113 [doi.org]
          Hu, L. and Chen, G. "Analysis of optical absorption in silicon nanowire arrays for photovoltaic applications [acs.org]". Nano Lett. 7, 3249-3252 (2007). doi 10.1021/nl071018b [doi.org]

          Quoting from that second paper:

          We found that, in comparison to thin films, nanowire array based solar cells have an intrinsic antireflection effect that increases absorption in short wavelength range.

          Essentially the nanowire arrays are acting as anti-reflection coatings and allowing the light to instead be absorbed.

  • I am f tired reading about cheap solar panals (Score:5, Insightful)

    by Anonymous Coward on Monday July 06, 2009 @01:04PM (#28596271)

    for last 5 years same shit gets posted over and over again - Cheap solar panals
    5 years later - in some cases panels went up in price

    • Re: (Score:2)

      by jandrese ( 485 )
      I think the take home lesson is that low cost is not the only factor in making a successful panel. You can't mass market a panel that degrades in 6 months, or that requires 500 times the power of normal sunlight to be efficient, or is so fragile that it breaks down if you walk near it, or involve a production process that can't scale up.

      I hope that at least one of these technologies will pan out finally, but in the meantime I'm hedging my bets and looking at other forms of energy as well.

    • Re: (Score:3, Insightful)

      by bcattwoo ( 737354 )
      I think the last line of the summary could be reworded: "We don't know how much these things will cost to make, but to get additional funding we had to come up with something less than what current technology costs and ten times less just sounds so sexy."

    • Re:I am f tired reading about cheap solar panals (Score:4, Insightful)

      by vertinox ( 846076 ) on Monday July 06, 2009 @02:22PM (#28597413)

      for last 5 years same shit gets posted over and over again - Cheap solar panals

      Umm... No. The price to produce them has gone down and is in fact the lowest it has ever been.

      It is just that the demand is outstripping supply [azcentral.com] so economics is causing a price increase.

    • Solar panels have dropped in price over the last 5 years....

    • Most of our electricity is used for the creation or movement of heat. Which is spectacularly dumb and inefficient.

      e.g.
      http://ducts.lbl.gov/calducts.htm [lbl.gov]

      Solar thermal panels can be up to 90% efficient. The vacuum tubes work in cold and cloudy climates. The energy they displace will directly reduce electricity generation costs, reduce CO2 emmissions and they are far far far cheaper than photovoltaics.

      For cooling look at evaporative cooling or simply pumping the heat into a local river or ocean... Most of Calif

      • Re: (Score:3, Informative)

        by Ironica ( 124657 )

        For cooling look at evaporative cooling or simply pumping the heat into a local river or ocean... Most of California's cities are sited near the Pacific... Yet air conditioning is the single largest consumer of electricity, by far.

        Well, yes, our cities are near the Pacific... but Downtown Los Angeles is some 15-20 miles from the ocean, and the LA River, while it is recovering its riparian habitat these days, is hardly up to taking on any significant amount of waste heat. You're talking about *maybe* being able to cool a few beach hotels this way... and that would probably have a detrimental effect on near-shore habitats.

    • Re:I am f tired reading about cheap solar panals (Score:5, Informative)

      by mcrbids ( 148650 ) on Monday July 06, 2009 @03:57PM (#28598725) Journal

      for last 5 years same shit gets posted over and over again - Cheap solar panals
      5 years later - in some cases panels went up in price

      Whine whine whine. It's been going on for much longer than 5 years. When I was in 5th grade, I did a report on PV electricity, and I read numerous reports that PV panels could be much cheaper soon.

      Truth is, all those funky predictions were right. Solar power HAS been dropping very steadily and very predictably all along [frozennorth.org] in its own version of Moore's law - PV prices drop about 6% per year per watt, cutting in half every 10.5 years. It's not dropping like a stone, but it's very predictable and very steady.

      What's been going on the last 5 years? Simple: supply and demand. For many reasons, people have become wary of using fossil fuels and are willing to invest more into solar, causing a sudden, worldwide deficiency in production capacity. Low-cost production companies like Nano-Solar [nanosolar.com] are ramping up production literally as fast as they are physically able.

      For example, Nano-Solar has, for all intents and purposes, unlimited funding, and has already sold out several years worth of production, even that which is not actually happening yet. They are buying huge rafts of warehouse space in the Bay Area, in what used to be automotive manufacturing areas.

      So the laws of supply and demand are working their magic, even though the response isn't instant. Your children will bask in a society powered by cheap solar electricity that you are funding right now, just as you benefit from the electrical power infrastructure built by your parents.

  • Cadmium ... (Score:4, Interesting)

    by Anonymous Coward on Monday July 06, 2009 @01:07PM (#28596317)

    Look at the toxicity of cadmium and all the environmental regulations that come with it. It's regulated to 1/10th the level of mercury in the EU RoHS (Reduction of Hazardous Substances in Electronics) legislation.

  • Creation of Electrons (Score:3, Funny)

    by Bucky340 ( 1020993 ) on Monday July 06, 2009 @01:07PM (#28596321)
    "the material surrounding the pillars absorbs light and creates electrons."

    Wow, creation Ex Nihilo or from other subatomic particles? That is powerful technology.

    • Re: (Score:3, Funny)

      by TeknoHog ( 164938 )
      Do you always have to be so negative?
      • Two atoms were walking down the street when another atom brushed by them.

        One of the atoms turns to the other and says, "Hey! That atom stole an electron from me!"

        The second atom says, "Are you sure?"

        "I'm positive!"

        ...or something like that...

  • Based on recent history... (Score:3, Insightful)

    by OpenSourced ( 323149 ) on Monday July 06, 2009 @01:08PM (#28596333) Journal

    Don't tell me. It'll be ready for mass production in 3 to 5 years. Somehow, I seem to remember stories like this from more than five years ago, and still, nothing happens and the solar cells are more or less the same as always.

    • Re:Based on recent history... (Score:5, Informative)

      by Marcika ( 1003625 ) on Monday July 06, 2009 @01:22PM (#28596561)

      Don't tell me. It'll be ready for mass production in 3 to 5 years. Somehow, I seem to remember stories like this from more than five years ago, and still, nothing happens and the solar cells are more or less the same as always.

      Don't be a universal cynic, inform yourself instead. Look up Nanosolar [wikipedia.org] and First Solar [wikipedia.org] on Wikipedia, and you'll see that they have been already mass-producing panels at one-third of the price of crystalline silicon panels for a year or two.

      "Nothing happens" is only true if you close your eyes to all the things that actually do happen.

      • Don't tell me. It'll be ready for mass production in 3 to 5 years. Somehow, I seem to remember stories like this from more than five years ago, and still, nothing happens and the solar cells are more or less the same as always.

        Don't be a universal cynic, inform yourself instead. Look up Nanosolar [wikipedia.org] and First Solar [wikipedia.org] on Wikipedia, and you'll see that they have been already mass-producing panels at one-third of the price of crystalline silicon panels for a year or two.

        "Nothing happens" is only true if you close your eyes to all the things that actually do happen.

        You accurately answered half of the posts about this story with this comment. It's true - we can go buy this stuff (which was 3-5 years away 3-5 years ago) right now.

    • Re:Based on recent history... (Score:5, Informative)

      by Spoke ( 6112 ) on Monday July 06, 2009 @01:35PM (#28596735)

      Surprise, there are already [nanosolar.com] companies [firstsolar.com] that are producing thin-film solar panels for less than $1/watt.

      The problem is that demand is so high for these inexpensive cells that at least for Nanosolar, you can't even buy them unless you are buying tons and tons of them. That leaves First Solar and those panels get significantly marked up because of the lack of competition at the low end of the market.

      That said, wholesale prices of traditional silicon panels are around $3/watt and as an end user you can get them for slightly above that if you shop around.

      But once the system is installed you're looking at a minimum of $6/watt currently. So while the panels are still the most expensive part of the system, pretty soon the other components (inverter, mounting hardware, wiring, labor) will exceed the cost of the panels.

      We're getting very close to the point where solar systems make financial sense for just about everyone. It already makes sense for any high electricity users who pay a premium for electricity. We'll probably see solar system pricing continue to drop over the next couple years as manufacturing capacity continues to come online.

      • Re: (Score:2)

        by nadaou ( 535365 )

        We'll probably see solar system pricing continue to drop over the next couple years as manufacturing capacity continues to come online.

        [Insert joke of galactic proportions here]

  • Conspiracy buffs rejoice! (Score:4, Funny)

    by ArhcAngel ( 247594 ) on Monday July 06, 2009 @01:10PM (#28596361)

    Once you install these on your roof you will only need to wear your tinfoil hat when you are outdoors.

  • Nanopillar Solar May Cost 10x Less... (Score:2, Funny)

    by Anonymous Coward

    I've got a nanopillar for you that costs... no wait, that sounded much better in my head. Um, nevermind.

  • "may" cost less (Score:4, Insightful)

    by Geoffrey.landis ( 926948 ) on Monday July 06, 2009 @01:15PM (#28596449) Homepage

    Nanopillar Solar May Cost 10x Less Than Silicon

    ...and then, it may not.

  • Come on do they really think we'll fall for printing solar cells on aluminium so we use them as tin-foil hats? We all know that in reality this is just a government plot to subvert the tin-foil hat movement and convert the hats into powerful mind-reading devices powered by the rays of the sun.

    Evil I tell you, evil.

  • Yay, Its time again for Solar technology Bingo! (Score:3, Insightful)

    by luckytroll ( 68214 ) on Monday July 06, 2009 @01:33PM (#28596711) Homepage

    Thats right folks - for every time you see the words "May", "Might Somday", "Could eventually", you get to cover a number.

    Bonus if you get to catch one or more instances of "In 5 years", "with continued funding", or "commercial quantities"

    It seems the only people making flexibles these days are also selling them for a huge markup, and the technology is a lot less efficient than the monocrystal cells. But at least you can buy it. Today.

    I used to actually follow up these articles by contacting the companies involved, and asking when they would be able to sell to me as a consumer. I still cant buy any of their products. Any of them.

  • Low cost until scarcity kicks in.... (Score:4, Interesting)

    by macraig ( 621737 ) <mark@a@craig.gmail@com> on Monday July 06, 2009 @01:36PM (#28596745)

    How plentiful is cadmium relative to silicon? Not so much, right? Isn't cadmium already pretty much spoken-for in other industrial and consumer electronics applications?

    Leave it to engineers not to consider the ugly realities of supply-and-demand economics.

    • Re:Low cost until scarcity kicks in.... (Score:5, Informative)

      by TheSync ( 5291 ) on Monday July 06, 2009 @01:54PM (#28597035) Journal

      How plentiful is cadmium relative to silicon?

      Worldwide known reserves of Cadmium are about 490,000 metric tons, and production is about 20,000 metric tons/yr. Cadmium is generally recovered as a byproduct from zinc concentrates. Zinc-to-cadmium ratios in typical zinc ores range from 200:1 to 400:1. Estimated world identified resources of cadmium were about 6 million tons, based on identified zinc resources of 1.9 billion tons containing about 0.3% cadmium. The average annual New York dealer price of cadmium metal in 2007 was $7.61 per kilogram ($3.45 per pound).

      The source of the silicon is silica in various natural forms, such as quartzite. Silicon is the second most abundant element (after oxygen) in the crust, making up 25.7% of the crust by mass. Word production of silicon is about 5.7 million metric tons/yr. The price for silicon ranges from $0.66 per pound for 75% ferrosilicon and $1.13 per pound for silicon metal.

    • Leave it to engineers not to consider the ugly realities of supply-and-demand economics.

      And leave it to random slashdot posters to not RTFA before posting bitchy comments:

      The researchers also intend to try other semiconductor materials for the pillars and surrounding material. Javey says that the fabrication process is compatible with a wide range of semiconductors, and other combinations could up the efficiency.

      Trying other semiconductor materials might also be important given cadmium's toxicity issues, Berkeley's Yang points out. Nevertheless, he says, "architecture is most important--materials we can continue working on. The beauty of this paper is the demonstration of how well the architecture works."

      • Re: (Score:2)

        by macraig ( 621737 )

        Any other compounds they might try are likely to be based upon elements even more scarce than cadmium. Did you notice that only toxicity was mentioned as a justification, not scarcity? Gallium, indium... all the other choices are just as scarce or moreso. Silicon, by comparison, is the second most abundant element, and the amount produced each year is about the same as the total estimated reserves of cadmium.

    • Re:Low cost until scarcity kicks in.... (Score:4, Insightful)

      by JustinOpinion ( 1246824 ) on Monday July 06, 2009 @02:25PM (#28597477)
      Their device uses a cadmium telluride (CdTe) active layer. Actually the tellurium [wikipedia.org] is the limiting factor since it is even rarer than cadmium. Of course that could change [wikipedia.org] depending on the economics of exploitation and what new sources are discovered. Whether Cd or Te is the limiting factor, devices based on CdTe (including the one in the scientific article) use a CdTe layer only 1 micrometer thick. So a metric ton of raw material would be enough for roughly [google.com] 171,000 m^2 of solar cells. This gives us 1 GW of power per 66 metric tons [wikipedia.org]. Not great, perhaps, but probably good enough to justify manufacture and distribution.

      Moreover, I don't understand the pessimism of:

      Leave it to engineers not to consider the ugly realities of supply-and-demand economics.

      How else do we consider these ugly realities if not to study available materials, test the limits of what works and what doesn't, build prototypes, publish results, and work towards commercialization... ? Other materials may eventually be used in real devices (either after a period of using the relatively rare Cd and Te, or perhaps well in anticipation of those supply problems). Even if the device, as presented, doesn't mesh up with the realities of current supply-and-demand, it is part of the process of getting from a problem ('we need energy') to economically-viable solutions.

    • Re: (Score:3, Informative)

      by mcgrew ( 92797 )

      Cadmium is used for red and yellow paints for artists, both oil and acrylic based paints. They're really bright yellows and reds, so the bright orange and yellow jackets road crews wear probably have cadmium pigments.

      I wonder what color these cells are? Will everyone's roof be red in the future?

  • Hard to estimate future cost (Score:4, Interesting)

    by nokiator ( 781573 ) on Monday July 06, 2009 @01:50PM (#28596977) Journal
    The language projecting the cost savings for this new solar technology is somewhat dubious as usual. Even if the developers of this technology have good reason to think that the cadmium sulfide based solar panel technology will cost 1/10th compared to today's cost of developing silicon based solar panels, what happens between now and when they are able to take this technology to mass production in five or more years?

    There is a massive world-wide technology complex driving the optimization of silicon based manufacturing technology. The amount of capital invested into silicon manufacturing process and tools is measured in tens of billions of dollars per year, if not hundreds of billions. If the conventional process improvements is able to achieve 20-25% cost improvement per year, in five years, the cost of panels based on conventional panels would be down to 25-30% of today's cost. A few hickups in the development of the new technology like yield or reliability issues can easily delay the mass deployment by a few years which will negate all cost benefits. Not to mention the possibility of cadmium prices going up if the volumes are picking up...

    And don't forget the cost of capital investment, which is already funded due to other "useful" applications in the silicon case. Most other technologies that tried to compete against silicon lost so far, not because of fundamental technical issues but because of the economics involved.

    I am not against developing new innovative technologies to achieve substantial improvements in the solar power area. However, it is best to keep the optimism about new and unproven technologies in control until they reach at least beta production stage...

  • What about total installation cost? (Score:4, Insightful)

    by IvyKing ( 732111 ) on Monday July 06, 2009 @02:19PM (#28597365)
    The cost of solars cell is low enough that infrastruture costs are a significant portion of the total installed cost. The quoted efficiency, 6%, implies that these cells would take up more area than silicon cells, and structiral support costs are proporional to area (I did see the text about possible doubling of efficiency). Another disadvantage to low efficiency cells is increased thermal loading.
  • There is demand for them. In colorado someone stole [kjct8.com] them off a public building near aspen.

  • Cadmium is one of the "toxic heavy metals" {insert music pun here} and because of this, no matter what amount is used and to any degree of value, it will be shot down by the enviro-namby-pambys who took lead outta my solder.

Slashdot Top Deals

He has not acquired a fortune; the fortune has acquired him. -- Bion

Close