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Quantum Dots Could Double Solar Energy Efficiency

dptalia notes the recent publication in Science of research demonstrating a way to use hot electrons in solar cells, resulting in an overall energy conversion efficiency of 66%. Here is the abstract in Science; access to the full article requires a subscription. "A team of University of Minnesota-led researchers has cleared a major hurdle in the drive to build solar cells with potential efficiencies up to twice as high as current levels, which rarely exceed 30 percent. ... Tisdale and his colleagues demonstrated that quantum dots — made not of silicon but of another semiconductor called lead selenide — could indeed be made to surrender their 'hot' electrons before they cooled. The electrons were pulled away by titanium dioxide, another common inexpensive and abundant semiconductor material that behaves like a wire."

7 of 112 comments (clear)

  1. But by when? by bhagwad · · Score: 3, Insightful

    Seems like I keep hearing of breakthroughs, but nothing ever seems to fucking change!

    1. Re:But by when? by Sockatume · · Score: 3, Insightful

      Things would go a lot faster if more people were saying "how can I make this happen?" and fewer "I was supposed to have a jetpack frownyface exclaimation mark question mark"

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      No kidding!!! What do you say at this point?
  2. Could, might, may... by luckytroll · · Score: 3, Insightful

    If I had a tribble for every time one of these solar energy articles came out with their pages full of nothing.... I could make a lot of fur coats.

    Could someone in the research field please hold on to their excitement until they can post a report that has words like "WILL, SHALL, DEFINITELY, HAS, IS" instead of the wimpy "could, may, might, has potential to, in 5 years if all goes well....."

    I got sucked in by one years ago and pestered the company for information about their new "product" which was due out "soon".... and that was nearly 10 years ago.

    So many advances in tiny little cells on a research bench, and so many promising advances. Yet none of them seem to show up at the local hardware store.

    I understand that advances in quantum materials science is cool, and can change everything just like the invention of the transistor did once. But seriosly folks - the number of speculative postings based on
    these barely germinated lab experiments seem a little bit like the kid who cried "Solar revolution", or was that wolf?

    1. Re:Could, might, may... by Sockatume · · Score: 5, Insightful

      It's a research paper, not a god-damned press release. Don't blame the scientists for publishing their awesome research in a prestigous journal, blame the journalists who treat every Friday as a chance to jizz out a couple of easy stories by rewriting articles in Science.

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      No kidding!!! What do you say at this point?
  3. Re:Econuts will be torn over this one by drinkypoo · · Score: 3, Insightful

    Not a problem; lead's not nearly as bad as the arsenic in some panels!

    We need to find a way to get usable arsenic out of contaminated soil. There are literally thousands of tons of it around the world, much of it slated for "cleanup" (secure burial). It's a lot less dangerous when you make it into a solar panel than when it's free to get into groundwater.

    --
    "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  4. Re:How much energy are we talking about? by CarpetShark · · Score: 4, Insightful

    You're confusing energy conversion efficiency with energy production. The main connection there is that less efficiency means more raw resources for the same result. They're certainly not the same thing.

    I think what the GP was getting at is something like, "This sounds way better than past solar conversion efficiency. Can we know build viable solar power stations? What about orbital solar power satellites? Where does this leave coal and nuclear power stations? What will the overall energy production strategy be, once this comes to market, given projected energy needs WHEN it will come to market?"

    That's not a set of questions you want to answer too hastily.

  5. Re:price not efficiency by smellsofbikes · · Score: 3, Insightful
    You need both. It'd be great to have dirt-cheap solar cells, sure, but current 20% efficient cells can produce the amount of power a house needs, mounted on the roof of the house. If you make dirt-cheap 1% efficient cells you need 20x the space, which exceeds the entire yard space of most suburban and urban houses. Then, you have a solution that only makes sense for huge power generation companies that can afford to buy up half of Nevada to cover it with solar cells and transport the power. If we can make reasonably-priced, reasonably-efficient cells we can have microgeneration at each individual house.

    While this isn't as much the case in very rural, very poor areas, where making kilometer-square solar arrays is viable, there's at least two orders of magnitude less money to be spent in such locations, so you're back to the same problem.

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    Nostalgia's not what it used to be.