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Power Technology

Avalanche Effect Demonstrated In Solar Cells 234

esocid writes "Researchers at TU Delft (Netherlands) and the FOM (Foundation for Fundamental Research on Matter) have found irrefutable proof that the so-called avalanche effect by electrons occurs in specific semiconducting crystals of nanometer dimensions. This physical effect could pave the way for cheap, high-output solar cells. Solar cells currently have relatively low output, typically 15%, and high manufacturing costs. One possible improvement could derive from a new type of solar cell made of semiconducting nanocrystals and could theoretically lead to a maximum output of 44%, with the added benefit of reducing manufacturing costs. In conventional solar cells, one photon can release precisely one electron. However, in some semiconducting nanocrystals, one photon can release two or three electrons, hence the term 'avalanche effect.' This effect was first measured by researchers at the Los Alamos National Laboratories in 2004, and since then the scientific world had raised doubts about the value of these measurements. This current research does in fact demonstrate that the avalanche effect can occur."
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Avalanche Effect Demonstrated In Solar Cells

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  • Wait and see (Score:5, Insightful)

    by Bananatree3 ( 872975 ) on Tuesday May 27, 2008 @12:39AM (#23552033)
    as with all emerging technology, I am going to wait and see as to how this R & D develops into a commercial application.

    However, I'll bet the keys on my keyboard that solar is going to be a lucrative market in the near future. Heck, it already is for solar cell manufacturers.

  • by Doc Ruby ( 173196 ) on Tuesday May 27, 2008 @12:41AM (#23552043) Homepage Journal
    Manufacturing solar PV cells is usually said to cost quite a lot of energy. But how much exactly (on average)?

    How many joules are consumed from raw materials to a deliverable PV cell of a given output wattage? Of the old "about 15%" (really about 20-25% these days), and of these new proposed "avalance" PV material ones?

    I want to compare that energy cost to the cells' projected energy contribution over their lifetime, which is about 30+ years for today's PV cells. How long would the new ones last in typical service?
  • by Jane Q. Public ( 1010737 ) on Tuesday May 27, 2008 @12:46AM (#23552079)
    Somebody else said this the last time solar cells were brought up, and it is just as relevant here:


    If all the "improvements" to solar cell manufacturing I have read about in recent decades became actuality, we would all have homes and cars powered solely by a 1-meter-square panel on the roof and the panels would cost $1 apiece.

    Please, either DO SOMETHING with this, or stop making predictions!
  • Let's be realistic (Score:5, Insightful)

    by actionbastard ( 1206160 ) on Tuesday May 27, 2008 @12:49AM (#23552099)
    Whether they're hairy [], nanotube [], or amorphous [], cheap, efficient solar cells are always going to be thirty years away as long as there is 'cheap' oil around.
  • by QuantumG ( 50515 ) * <> on Tuesday May 27, 2008 @12:51AM (#23552115) Homepage Journal
    Yes, to the ever increasing market of solar cells. They put em in calculators and on caravans and ummm.. uhh.. those remote weather sensors and, uhhh, emergency phones on the side of the highway.... oh yeah, and satellites and NASA robots. As you can see, clearly the market is massive and the competition is cut-throat.

  • by hyades1 ( 1149581 ) <> on Tuesday May 27, 2008 @01:12AM (#23552237)

    We seem to cavil about a few million dollars, or even a few hundred million, being spent to jump start emerging energy technology, but we have no problem spending billions on oil industry subsidies.

    We need to acknowledge that any new tech investment involves high risk. Success brings high rewards. We accept exactly this reasoning when oil executives tell us that oil exploration is expensive and risky, and therefore requires continuing subsidies even when record profits are rolling in. A few million spent on alt energy research that tanks, however, is usually reported as a "this is what happens when you listen to the tree huggers" story.

    An attitude adjustment as 'way overdue, and a rediscovery of our spirit of adventure and innovation. Perhaps putting some money into finding out whether this kind of solar cell works and can be mass produced would be a place to start.

  • by phantomfive ( 622387 ) on Tuesday May 27, 2008 @01:20AM (#23552295) Journal
    Man, let me tell you about skylights. I have a skylight, and I thought it was cool. Here's how it works: I get free light all day long, except at night when there isn't enough light coming in through the window.

    I get free heating all summer long, but in the winter it's too cloudy to make a difference. Yeah, skylights sound good and all, but give me a solar panel over that any day.
  • by jimmyhat3939 ( 931746 ) on Tuesday May 27, 2008 @01:31AM (#23552359) Homepage
    I'm often confused when I see articles about how great it is to improve the efficiency of solar cells.

    To me, the big issue is not efficiency but cost per watt. Many regions of the world have plenty of the land, particularly energy guzzlers like the US. What we really need is a super-cheap way to use that land for solar generation.

  • by Anonymous Coward on Tuesday May 27, 2008 @01:37AM (#23552403)
    In theory - solar cells built around these new semi-conductor materials would be less expensive to manufacture, with a doubling or tripling of electrical output per panel.

    Higher output, lower unit cost - isn't that exactly how one gains a lower cost per watt?
  • by QuantumG ( 50515 ) * <> on Tuesday May 27, 2008 @01:52AM (#23552503) Homepage Journal
    A subsidized market is hardly a market at all. The *fact* is that there are few manufacturers of solar cells.. and most of them are differentiated anyway, so they don't compete.

  • by Jane Q. Public ( 1010737 ) on Tuesday May 27, 2008 @01:57AM (#23552519)
    Phone watches have been available for years now (so have television watches, but not watches that do both).

    What is holding up your flying car is not the car itself, it is infrastructure. Letting everybody who could afford to fly go wherever they wanted to, uncontrolled, would be pure mayhem. Death, destruction, and injury on a massive scale. Until they get absolutely reliable tracking and automated control, there will be no commonly available "flying cars". And the technology to do that, i.e., a distributed communications and computing network, did not exist until the cellular phone network was established (and greatly improved).

    Now that we know we have the tracking and control technology, you might start seeing flying cars. But it is really no surprise that it has not happened before.
  • by jberryman ( 1175517 ) on Tuesday May 27, 2008 @02:02AM (#23552545)
    We need to wake up, and start the new Manhattan Project for energy; I don't think we can wait on the Free Market for this one.
  • by Mathinker ( 909784 ) on Tuesday May 27, 2008 @02:19AM (#23552647) Journal
    There is no such thing as irrefutable in science. In fact, some people attempt to define science as the pursuit of knowledge which can be corroborated and refuted using the "scientific method" (to preempt a lot of comments: I said "attempt to define", because this definition rapidly becomes circular unless you are very careful, and it is not clear that defining the "scientific method" is easier than defining science itself).

    OTOH, I rather doubt that the scientists themselves claimed irrefutability here. The journalists are probably to blame.
  • Flying Car? (Score:4, Insightful)

    by camperdave ( 969942 ) on Tuesday May 27, 2008 @02:22AM (#23552661) Journal
    And while your on it ask them what's holding up my flying car?

    Anti-grav units? Powerful downward facing thrusters? Wings? Rotors?

    Truth be told, there's nothing holding up your flying car except the name. It's not a flying car. It's a personal aircraft, and they come in many different sizes and shapes, from ultralights, LongEZs, and autogyros, to Beavers, Cesnas and Learjets.
  • by dmgxmichael ( 1219692 ) on Tuesday May 27, 2008 @03:35AM (#23552991) Homepage

    Imagine for a moment if we geeks hadn't come up with DNS but instead tried to use a small handful of machines to handle domain name resolution. The Internet would collapse rather quickly no?

    Funny then that to date our power grid is based on a centralized model. Sadly, as much as 20-30% of all power generated is lost during transmission over the grid.

    Now effective solar panels and batteries to go with them would allow us to move to a more decentralized model. Imagine whole neighborhoods creating most - though not all - of their power needs. If the panels can get to around 80% of the needs of the house then the current power plants we have can be the only ones we need for awhile.

    Or even better, instead of having massive plants with a huge footprint make use of smaller pup nuclear reactors - about the size used in a naval ship. One of those could be placed where the power substations are now and pick up the slack that the solar panels can't fulfill. They wouldn't present any real contamination danger as once their fuel was spent after 30 years or so you truck out the entire unit and refurbish (i.e. refuel) it under controlled conditions in a remote area - while in service the internals of the thing aren't opened up.

    These things also wouldn't have to make as much power as the current power stations because, by virtue of being closer to the customers they serve, they wouldn't lose as much power in the lines.

  • by Anonymous Coward on Tuesday May 27, 2008 @03:36AM (#23552999)

    Since when is $135/barrel "cheap"?
    @ $135/barrel, people are still wasting energy left and right. So it is still cheap.
  • by dmgxmichael ( 1219692 ) on Tuesday May 27, 2008 @03:44AM (#23553033) Homepage

    The problem isn't oil - it's the abuse of it. Like an adict we've allowed oil to change the entire structure of our nation and our society. When the oil is gone this structure will not be sustainable.

    It won't be armageddon. People will simply move back into the cities. The suburbs will become ghettos just as the inner cities are now and then they will die out. By the end of the century New York, Chicago and the other large cities of the US will contract back into the boundaries they had in the year 1900 before the oil infection took hold. It will only occur when people have no other choice - but now that we are beyond Heubert's peak that day is fast approaching.

    Another sign of this is that even as the housing market overall is in crisis real estate in the inner cities has actually increased in value. Part of this is the lessors of such properties are usually corporations or affluent individuals, the other part is that the price of oil's rise creates a condensation pressure on cities that is only beginning.

  • by Bananatree3 ( 872975 ) on Tuesday May 27, 2008 @05:38AM (#23553545)
    Where can I sign up? Sounds like good job.

    Tidal/geothermal power are much more constant and predictable sources than solar or wind. However, I think all of these renewable technologies are each a piece of the overall energy puzzle. Solar, Wind, Tidal, Geothermal...they've all got strengths and individual industries working for them. The current model of a dominant source is fading away into a more diversified energy market. "Never put all your eggs in one basket", as they say.

  • by Kupfernigk ( 1190345 ) on Tuesday May 27, 2008 @05:59AM (#23553661)
    Do you have any idea how long it takes to commercialise a technology in volume? Obviously not.

    If you actually read up on solar cells instead of sounding off like an idiot, you would know that the cost per watt is dropping quite fast, durability has doubled in the last 5 years, that Sharp are making cells which are nearly twice as efficient as much of the competition and they are being sold as roof panels, that the recently opened German factory can sell everything it makes for many months ahead.

    Nobody has ever pretended that a 1 sq M panel would power anything large. There is only so much sunlight, and nobody has ever pretended the second law of thermodynamics would be broken. No-one has ever pretended that 1 sq M panels would cost $1 apiece; you could not make a structure to withstand wind loading that cheaply. There is a huge difference between actual forecasts of an eventual $1 per peak watt, and $1 per sq M. $1 per watt works out at about $140 per sq M for a 14% efficient panel.

    To the people who modded this insightful: if you can't tell an obvious troll from engineering reality, plase hand in your geek cards now and go play with Facebook.

  • by Ihlosi ( 895663 ) on Tuesday May 27, 2008 @07:44AM (#23554167)
    Water heating - sure! Light - sure. But heating? There's not enough angle when the sun strikes the earth in the wintertime, that's why it's cold - the energy is absorbed by the atmosphere.

    Erm. Some of my colleagues heat their (superinsulated) houses with solar, with a small electric auxiliary heater. This year, they didn't have to use the auxiliary heater from late January on.

    So, sure, you may not be able to heat your house with solar all the time, and in all latitudes, but you can use it to significantly cut your usage of other forms of power for heating.

  • by pedestrian crossing ( 802349 ) on Tuesday May 27, 2008 @09:44AM (#23555249) Homepage Journal

    The subsidies are a temporary measure that serve to kick-start the build-out of the infrastructure to support a new market in the face of opposing forces, such as cheap coal or subsidized nuclear.

    IMHO, "free" markets are not always the most efficient way to achieve change, especially when there is a large capital barrier to entry.

  • by mhall119 ( 1035984 ) on Tuesday May 27, 2008 @09:45AM (#23555259) Homepage Journal

    Why can't we have a leader pledge to reduce America's dependence on oil by 50% in 10 years? Sounds just as possible to me as Apollo XI would have in 1960. And it's obviously more practical.
    It's significantly harder if you go and think it through. The Apollo project required the efforts of maybe several thousand people, where as reducing consumption of oil will require the efforts of millions of Americans. The Apollo project required the construction of several facilities and large infrastructure in only a handful of locations, where as reducing fossil fuel use will require a nationwide architecture upgrade, and at least hundreds of large facilities.

    If the Apollo program were at the scale required for reducing oil consumption, we'd have colonized most of the moon by now.
  • by dpilot ( 134227 ) on Tuesday May 27, 2008 @11:08AM (#23556489) Homepage Journal
    I generally agree with your scenario, with one exception. I expect to see some fraction of the suburbs survive with telecommuters. Similar to energy costs pushing physical workers back close to their workplace, I expect to see those costs push "telecommutable" jobs into telecommuting, and an expansion of technologies that enable telecommuting.

    The other piece of work that needs to be done behind all of this is to make the suburbs more foot-friendly. Once you don't need to drive to work, the next thing is to not have to drive, or at least not as far, to get the basics of living. I'd expect to see humongous grocery stores fade back into the neighborhood supermarkets.

"Never give in. Never give in. Never. Never. Never." -- Winston Churchill