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New Solar Panel Design Traps More Light

Posted by CowboyNeal on from the thousand-points-of-light dept.

GoSun wrote in with an article about new solar panels that opens, "Sunlight has never really caught fire as a power source, mostly because generating electricity with solar cells is more expensive and less efficient than some conventional sources. But a new solar panel unveiled this month by the Georgia Tech Research Institute hopes to brighten the future of the energy source." The new panels are able to produce sixty times the current of traditional models.

9 of 334 comments (clear)

  1. *yawn* by Spazntwich · · Score: 4, Informative
    From TFA:

    But current is only half the equation. To generate electricity, a cell has to churn out voltage as well.

    And so far, that's where Ready's invention has fallen short. There's still too much resistance within the cell to produce the type of electricity that's needed. But he said he'll now focus on reworking the interface to smooth out the kinks.

    This is non-news. Multi-layered cells have been talked about forever, and haven't they all previously run into similar issues?
  2. Outdated canard by StefanJ · · Score: 4, Informative

    I'm tempted to say "Cripes, This Again," because it comes up in almost every discussion about solar cells.

    Instead I'll say: That may have been true once, but it isn't any more. It will become less and less true with time, as learning economies and economies of scale come into effect.

  3. Re:Is solar really green? by evanbd · · Score: 4, Informative

    Electric power delivered to me at home is about $0.10/kwHr. Solar panels are about $5/w for the panel or a bit less. Grid tie inverters are a bit under $1/w (at least in the low kilowatts range). It's a bit pricier if you want batteries and completely off-grid, but I'll assume a simple grid tie system designed to reduce your utility bill.

    That means your solar panel needs to produce 60,000 wHr of electricity per watt to pay for itself, ie it needs to operate for 60k sunny hours. That's about 25 years or so, in a reasonably sunny mid-latitude climate. That's about the life of the solar panel.

    Now, that only sort of answers how green they are. In terms of carbon budget, they probably come out ahead -- not all the cost of the solar panel pays for the energy to make it, there are other costs as well. In terms of total pollution, I don't really know -- there are some nasty chemicals involved, but I think the silicon industry in general is pretty good about disposal (I don't know details off hand, sorry). I don't think there are any subsidies on the manufacturing, just tax credits and such when you buy them, so I think I've fully accounted the costs.

    So, overall, I'd guess they're marginally greener than the alternatives. Solar panel prices are falling rapidly, which means they're getting greener to make (at least if we assume manufacturing techniques aren't getting messier). I'd guess they start to come out clearly ahead in the next couple years.

  4. What a useless article.... by dyslexicbunny · · Score: 4, Informative

    It's like a third grader's book report... Why don't we just get the water from the well... from GTRI's site

  5. Re:Bad math.. by Technician · · Score: 4, Informative

    Current solar cells are ~20% efficient... you can't do better then 100% obviously.

    Nobody claimed they produced 60 X the power. In DC circuits Volts X Amps = Watts. 60 times the current does not equal 60 times the power if the voltage is not the same. The article is very clear, the voltage is way down. They make no power claims. It's even implied that the voltage is near zero. These panels may be less effecient than the curent generation. They are working on raising the voltage. Good luck and I hope they come out with some power figures soon.

    --
    The truth shall set you free!
  6. Myth. Solar has a VERY good energy payback by taharvey · · Score: 5, Informative

    This is one of those grand myths that the public just can't shake. Photovoltaic's have a very good energy return on investment (EROI).

    The energy payback peroid for various PV cell types are:
    Crystal Silicon: 3.3 years
    Multicrystal Si: 0.8 years
    CIS: 0.4 years

    To put that is perspective of EROI:
    Photovoltaics (Si): 60:1 - 10:1 (based on above)
    Wind: 60:1
    Coal(US average): 9:1
    Nuclear (light water): 4:1
    Oil (mid-east): 10:1 - 30:1
    Oil (US): 3:1 or less

    And that is keeping in mind that the lifespan of PV is calculated at 30 years, an arbitrary number picked to equalize it with the life of a coal or nuclear power plant, however are panel warranties are 20-30 years alone. There is no reason to believe that the average lifespan of a PV panel won't be 40-60 years or more.

    1. Re:Myth. Solar has a VERY good energy payback by taharvey · · Score: 5, Informative

      Three points:

      1. My previous post was about Energy return on Investment. In other words, how much energy must be invested to extract another amount of energy. Not economics. Different issue.

      2. The economics of solar however, are based on many issues. One such issue is it is being done on an inefficient small scale, by small time installers. Your Solar system would use around $45,000 in PV panels. Toss in another $7,500 for inverters, racks, etc. So you end up with around $30,000 in labor and profit - rather steep (find another installer). However, PV is currently competitive with some electric rates. On a equipment basis PV can produce power at around 8 cents/kilowatt hour at current prices - the rest is up to labor rates.

      3. The solar market is a supply limited market, which is pushing prices up. Right now world-wide demand is outstripping supply by ~30%. It is seriously keeping prices inflated. Blame capitalism. Right now PV manufactures can charge whatever they want. But as the supply catches up, you see things change in the next 5 years.

      4. Technology and manufacturing advances are bringing down costs as we speak - the question is when that will reflect in prices.

      5. It is also a question of economic externailities. The US invests HUGE resources in securing the middle-east region because it has a critical resource: oil. Some estimates of the Iraq war alone, bring the US cost to $2 trillion. For the same amount we could have replaced 33% of our electric production with solar - proving free electricity in peripituitary.

  7. That's not news by mkwalker · · Score: 4, Informative

    Where's the news in a half finished project that doesn't deliver any benefits (so far) on existing technologies? Who was the fool that got suckered into producing an infomercial?

    This is news: http://www.abc.net.au/catalyst/stories/s1865651.ht m

    Sliver cell solar technology. This was on Australian TV in March. Generating the same amount of power using a fraction of the silicon required today. Brilliant.

    --
    Why doesn't Perry think referring to cream cheese as cow fudge is funny?
  8. not quite by minuszero · · Score: 5, Informative

    Actually, this approach is a different one to the multi-layered aproach you are probably referring to.

    Said multi-layered approaches use multiple pn junctions with differing band-gaps, all on top of one another. This allows them to capture a broader spectrum of incoming light energies, thus increasing efficiency.

    The approach referred to in this article is attacking a different problem - using a 3-D 'nano-tower' construction for the pn junctions in order to minimise the reflection of light, thus capturing more of it and therfore being more efficient.

    While I'll agree that even this idea for such nano-cells has been around for a little while, it is still in very early stages of development, and has a long way to go. It is encouraging to see apparent evidence that the concept does work, however!