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Nanotech Solar Cell Minimizes Cost, Toxic Impact 95

bonch writes "Researches at Northwestern University have developed an inexpensive solar cell intended to solve the problems of current solar cell designs, such as high cost, low efficiency, and toxic production materials (abstract). Based on the Grätzel cell, the new cell uses millions of light-absorbing nanoparticles and delivers the highest conversion efficiency reported for a dye-sensitized solar cell."
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Nanotech Solar Cell Minimizes Cost, Toxic Impact

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  • Oh neat! (Score:5, Insightful)

    by Narcocide ( 102829 ) on Wednesday May 23, 2012 @06:43PM (#40094561) Homepage

    More ground-breaking world-changing solar technology that will neither break ground or change the world because it will never make it to the consumer.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      You're right, no improvements to solar panel technology ever reach the market. That's why the cost of solar power has been in freefall for several years.

      No wait, I forgot, it's all the Chinese, right? They flooded the market SO HARD that it broke the space-time continuum and made solar prices fall even before they entered the market at all!

      • For whatever it may (or may not) be worth to an anonymous coward that apparently failed entirely to get the point of my statement, I actually am *opposed* to the currently restrictive and self-destructive import tariffs the US has been placing on exported Chineese solar panels. I'm sick of the pissing contests and the vapor ware. I just want more cost-effectively cheap solar panels and frankly I long ago stopped caring where they even come from. I don't necessarily speak for my other US brethren, but I w

        • by geekoid ( 135745 )

          You are a short sight ass. You would make great CEO material.

          The expensive part of solar is the installation.
          I suspect you lack the financial acumen to look 20 years down the road. Again see my first statement.

          But you keep ranting about your short sight misconceptions on the Internet, I'm sure looking like an idiot will help you're case.

          • Come on. I'm serious here. Certainly you've got a better counter-argument than "if you can't afford a solar panel array that takes 20 years to pay for itself you don't deserve one."

            • by mellon ( 7048 )

              Anything that pays for itself in 20 years can be paid for on time. There are companies forming around this very idea today. You buy the panels, install them at someone's home, and they pay you monthly for the panels. You deduct interest and depreciation, and suddenly the panels cost a lot less than they did. The only sad thing is that this can only be done by businesses—private individuals can't write the panels' depreciation off as a business expense.

              • No it can't. Let me introduce you to an idea from economics. Suppose you have some resource, any resource. It costs 200 kAh (kilo-ampere-hours) to place, and pays 10 kAh per year in useful capacity.

                At moment 0, you're down 190 kAh, and you've got to wait 40 (! not 20) years to build another. If you're useful lifetime is 20 years, it's essentially useless and merely exposes the owner to a large amount of risk with no actual benefit.

                You see the problem (I'm using kAh instead of dollars to make it clear that y

                • by mellon ( 7048 )

                  Amp-hours? That's not a measure of energy consumed. You must have meant watt-hours. So suppose you have a solar panel, which costs 200KWH to place, and pays for that energy consumed in four years. Then after 20 years, it has generated five times as much energy as it consumed on installation. So if you amortize its cost over 20 years, without any tax deductions, at, say, 5% interest, then you have to pay 2.4KWH per month. And for the life of the solar panel, you get back 4KHW/month. Your net pr

          • by jd2112 ( 1535857 )
            Shareholders care about short term stock price increases. Anything long term is a problem for whoever they sell thier shares to.
            • That is only true of companies that pay no/little dividend. People who own those are speculators.

              I own stock in several Canadian oil and gas companies that all pay more than a 5% cash dividend. (One has an 11% dividend because I bought it at an undervalued price.) The stock going up or down from month or month doesn't matter to me, what matters is the dividend yield relative to what I paid for those shares and what the company is doing to maintain or increase the dividend over the long term. One came out
          • You are a short sight ass. You would make great CEO material.

            By the way... Thanks! I'm totally putting that on my resume.

          • Re:Oh neat! (Score:4, Insightful)

            by Xeranar ( 2029624 ) on Thursday May 24, 2012 @12:20AM (#40096759)

            Of course the expense in solar power is installation but we've proven that for middle and lower economic class citizens cost of entry is usually the barrier for most advances. Picture the advance of the automobile. At the turn of the 20th century most people used mass transit (both public and private) by the turn of the 21st century that was relegated to the poorest of our society only, yes, I know exceptions exist but fundamentally I am speaking about the vast majority of Americans that live outside of the Big-5 cities. The cost of covering most dwellings in the US is negligible compared to the power savings they would generate if the government subsidized the initial installation. As panels would wear out unevenly cost of replacement would become manageable for the average middle-class household. Single high quality panels are sub-$1000 and in my area are hovering around $5-600. That's a manageable cost compared to the 25K+ it can run to install. Thus it is simply a question of how do we get the entry barrier low enough to make the argument feasible. New construction would be an obvious choice as tacking 25K onto the asking price of a home already north of 150K is minimal considering the immediate savings gained. But currently built homes would need the most government initiative to make it function. I picture essentially the TVA done over. Incur the debt today to increase productivity tomorrow.

            Then again replying to Geekoid is pretty much feeding a troll if his past comments are anything. He's a walking encyclopedia of stupid thoughts and insults laced together to appear pseudo-intellectual.

            • $25k to install, WTF? Why does it cost so much? Seems like it should be possible to DIY if you have the electrical knowledge...

              • Electricity is dangerous.

                So you need to have it at least validated by a licensed electrition if you are in a municipality.

                Also, if you don't set it up right, when power fails, you are sending power into lines which the technitions think are empty.

                This requires a switchback circuitbreaker. Which means your entire house has to be brought up to code and costs (at last check) between $2k and $3k.

                Do it yourself types can do a lot of the work but currently- all the panels I know require soldering (sp) - I think

              • by cusco ( 717999 )
                Almost no one does any more. My neighbor had an electrician at his house one day. I asked him what was up and he said that an outlet broke in the kid's room so it had to be replaced. Not a stupid man, nor a rich one, but the idea that he didn't need to pay for something like that was utterly beyond him. He didn't seem to believe me when I told him that I had completely re-wired our previous house by myself.
              • It was a general nice round number. Most of that cost is honestly the panels themselves. You told just buy 10 for a house, you buy more like 15-25 and then you're paying 5-10K for installation which is still fairly cheap for actual roof work on the scale it's being done at.

            • by Specter ( 11099 )

              "New construction would be an obvious choice as tacking 25K onto the asking price of a home already north of 150K is minimal considering the immediate savings gained."

              I think you should run your numbers again. Adding $25K to a typical 30 year mortgage at 3.6% is going to add about $115 dollars to your mortgage payment per month and that number's already low because I'm assuming you have excellent credit and I'm not including the effect on your property tax.

              What's the average electricity bill for an average

              • Thank you for breaking down the numbers. If anything if you can afford a $1200+ mortgage the addition of of what amounts to less than 10% increase per month should be negligible for the household. On top of that if we built up the smart grid that funneled most of the excess residential electricity into offices during the day and then used smaller power plants or battery packs using the offices downtimes (early evening, early morning, weekends) to offset some houses may see a net gain as they sell their el

          • by Lumpy ( 12016 )

            "The expensive part of solar is the installation."

            Hmm, I better go write someone a check because for my install because it was not the expensive part.

            I laid out 50% of my install costs on the panels alone.

            If you hire COMPETENT electricians you get it done quickly and no more expensive than having a generator put in.

          • I've wanted to go solar for a long time.

            Here's the problem.

            Right now, given $40k, I can get a consistent, tax free, risk free return of $1,800. I'm getting that now in fact.

            That's more than my electric bill.

            Due to the drop in natural gas prices, 10 cfl bulbs, six LED bulbs, and some shopping around, my electric bill is down to $880 per year- and that's locked in for three years. That's in a climate that is over 90 degrees for about 100 days a year.

            Right now, I've gotten a much bigger return from buying si

        • Having the most expensive electricity in the world according to wiki []
          I am looking forward to getting my 20*250Wp panels installed next month.
          Even with current prices, my installation will have paid for itself in 7 years, since I can use the grid as a "battery".

      • by Lumpy ( 12016 )

        No it made the rich CEO's of the few US solar companies whine like babies to Congress.

        Wah, I cant afford a new Mazarati every 4 months! make the bad china people stop! WE cant let solar get to the point that the poor can afford it! WAH!

        Yeah, I'm pissed as hell at the US cell and panel makers for being whiny bitches and refusing to compete.

  • He mentioned that this new solar cell design was intended to solve (among other things) the "low efficiency" of current designs.

    According to TFA, the new design has a 10.2% conversion efficiency, as opposed to the 11-12% efficiency of the "Gratzel cell" it was supposed to improve upon.

    It was further noted (in TFA) that traditional cells have up to 20% efficiency.

    • by balzi ( 244602 ) <matthew&awma,au,com> on Wednesday May 23, 2012 @07:09PM (#40094819)

      It's important to note though, that if you can make twice as much panel area for less money, then you are being more efficient.
      At the end of the day they are aiming for two different efficiencies:
      1. A lower $cost/output
      2. A higher output/environmental-footprint ratio.

      I've heard that currently the rule-of-thumb for Photo-Voltaic arrays is 4 years operation before they pay for themselves. Maybe this new technology will lower that significantly

      • It's important to note though, that if you can make twice as much panel area for less money, then you are being more efficient.

        This is true, assuming you don't have a limit as to the area of panels you can deploy (rooftop solar installations are slightly limited by the area of the roof).

        Note though that TFA specified high cost and low efficiency as problems solved by this design. In spite of the lower efficiency of the design, and without bothering to mention the actual cost at all...

        In other words, lot

        • by balzi ( 244602 )

          This is true, assuming you don't have a limit as to the area of panels you can deploy (rooftop solar installations are slightly limited by the area of the roof).

          I agree. If I gave them the benefit of the doubt (deservedly or not), I'd say that they are at least hoping to provide a cheap and environmentally friendly choice when space is not the issue.

          In context I think they are working from this starting point: "the Gratzel cell is a great concept, but it leaks, so let's see if we can improve on it so it's viable for the mass-market."
          If they succeed, at worst we'll have an "green" alternative to current Silicon-based PV arrays, and at best we'll have a system that's

      • by c0lo ( 1497653 )

        It's important to note though, that if you can make twice as much panel area for less money, then you are being more efficient.

        The prices for PV panels are already low enough to start considering other factors. For instance: available area for PV panels installation - it starts to matter for "domestic solar energy producers" (my current situation now, having to decide what offer I should go with).

    • by Waffle Iron ( 339739 ) on Wednesday May 23, 2012 @09:55PM (#40095953)

      The first part wasn't directly comparing the new cells to Gratzel cells. They said that solar cells *in general* suffer from problems like low efficiency, high cost, short lifetime, and toxic and/or rare ingredients. Most designs suffer major drawbacks in at least one of these areas.

      This new cell seems to address all of the above, while giving reasonable 10% efficiency. In particular, it avoids costly and energy-intensive crystalline silicon, and the most obscure element they mention is cesium, which isn't all that rare.

      If they really are able to cheaply stamp long-lived cells out by spreading an electrolyte solution between a couple of plates, it could indeed become a big deal.

  • Not bad, actually (Score:5, Informative)

    by tocsy ( 2489832 ) on Wednesday May 23, 2012 @07:33PM (#40094997)

    Before we get a lot of comments saying "what's so good about this?" it's actually pretty interesting. I did some undergraduate research with dye-sensitized solar cells (and am currently a graduate student researching inorganic semiconductors) and the basic thing you hear is that if you can get an organic solar cell to 10% efficient, they will be viable because they're so much cheaper than inorganics. While this may be true, the problem with dye-sensitized cells is, like they say in the paper, that they degrade in a rather short period of time. I saw this first-hand doing research on them - we had to make sure our batches were kept in darkness while making them otherwise the solution would degrade in a matter of hours, and after they were made I believe they only lasted a few months. If you can make 10% efficient organic solar cells that will last as long as inorganic ones (typically 20-30 years), you have a very attractive alternative to brittle, expensive and often toxic inorganics. I didn't see in the paper how long their new cells are supposed to last but anything you can do to make it more stable is going to help.

    • Unlike the GrÃtzel cell, the new solar cell uses both n-type and p-type semiconductors and a monolayer dye molecule serving as the junction between the two. Each nearly spherical nanoparticle, made of titanium dioxide, is an n-type semiconductor. Kanatzidisâ(TM) CsSnI3 thin-film material is a new kind of soluble p-type semiconductor.

      The Ti02 part has been known for at least a decade - the new bits are the CsSNI3 parts. IIRC many used platinum here instead.

  • by barv ( 1382797 ) on Wednesday May 23, 2012 @07:44PM (#40095085) Journal

    There are three factors that must converge to make it economically sensible to go solar electric.
    1). Grid parity. This is when the amortized cost of power from the solar electric system costs less than power off the local grid.
    2). When the cost per KWH per year stops dropping so rapidly. A corollary of Moore's law applies.
    3). Storage. We need a low cost & efficient power storage system. Flywheel, hydro, battery, even hydrolysis. Lightweight batteries or hydrogen fuel cells that could be swapped into the car would be best.
    At the current technology curve, it should be here within a decade in the sunny parts of the world.

    • (2) I don't know how much that factors in except psychologically. If going solar makes sense according to (1) then go for it. Yes, it will likely make even *more* sense next year, but that's a year the current system could've already been paying for itself. Prices need to be falling pretty fast to make that a good deal, especially now that the break even period is in the 5-10 year range.

      It's much like buying a computer - yes, I could get an even better system cheaper next year, but that doesn't help me

  • From TFA, it is only 11% to 12% efficient nearly half, of conventional solar panels which are themselves woefully inefficient. If you want to be commercially viable, you have to meet or exceed that target, not what prior iterations of your own method produce.
    • by Spodi ( 2259976 )
      Not really. If you can be 50% less efficient than the competition, but for significantly less of the price, it is still a better deal for a lot of people. Efficiency only matters when the desired generated energy demand is too great for the available area. Since most buildings do not have solar on them, there is plenty of places to throw in lower-efficiency solar panels.
      • by Lumpy ( 12016 )

        Until you discover the traditional Monocrystalline and Poly panels also will last 30 years and these have no proven longevity so you have to assume they will be dead in 5. Suddenly they have almost no value.

        • You would think so, but if you can sell these for $10 instead of $100 people won't care than they generate half the power and last 1 year instead of 30. If people cared about quality Wal-Mart would have trouble pulling a profit.
          • You would think so, but if you can sell these for $10 instead of $100 people won't care than they generate half the power and last 1 year instead of 30. If people cared about quality Wal-Mart would have trouble pulling a profit.

            Wrong, If people thought the quality of Wal-Mart products was unacceptable, THEN they would have trouble pulling a profit. Given the price, the quality is acceptable for most people.

            "Quality" is relative. A $30 microwave may indeed only last 4 years and have a 5% defect rage compared to a $100 microwave that lasts 8 years and has a 1% defect rate, but the consumer may value the extra $70 more than the lower defect rate and longer lifespan and so choosing the $30 microwave is the correct choice. Not to m

  • If it wont last 15+ years it's a failure.

    Just like this thin film crap all over the place from china, works great but loses 40% of the output in 12 months and then slowly dies within 5 years.

"If it's not loud, it doesn't work!" -- Blank Reg, from "Max Headroom"