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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.

7 of 334 comments (clear)

  1. Efficiency is not really important by EmbeddedJanitor · · Score: 5, Insightful
    The power convesion ratio is not really that important in itself. The only really important measure is $/watt.

    If you can get low $/watts with low efficiency that would be OK. Tile your house with the stuff, use it as the external covering for buildings.

    That is one of the major problems with PV showcases like the Australian solar race. they push efficiency more than $/watts which is my the winning cars cost hundreds of thousands of dollars.

    --
    Engineering is the art of compromise.
    1. Re:Efficiency is not really important by EmbeddedJanitor · · Score: 4, Insightful
      The important practical measure is $/W. There are many ways this might be impoved and improved efficiency is one of those - potentially. What I say is that efficiency improvements that improve $/W are important and those that don't are not (or very much less important).

      Many improvements in efficiency are through more expensive processing etc resulting in more expensive PV. The World Solar Race favours the team with the best efficiency, even if that costs hundreds of thousands of dollars. Much of the PV research is geared towards efficiency and this is the measure by which they compete (eg. http://www.boeing.com/ids/news/2006/q4/061206b_nr. html).

      This focus is detremental from a practical position of solving the energy crisis. While the big research dollars are focussed on efficiency we will continue to have PV that has useless $/W. It is far more important to ignore efficiency and focus on $/W.

      I won't use PV if it costs me $20,000 to fit a PV array. If I could fit a $2000 PV array we'd be talking. So what if that takes up 50 square metres of roof space instead of 5? Cheap stuff could even be made into roofing tiles. It is reducing the $/W that makes PV practical.

      It is a real shame that Boeing will spend huge dollars to inflate their egos with high efficiency while more practical programs like http://masseynews.massey.ac.nz/2007/Press_Releases /04-04-07.html struggle.

      --
      Engineering is the art of compromise.
    2. Re:Efficiency is not really important by s_p_oneil · · Score: 4, Insightful

      No, $/Watt is NOT the only important measure for PV cells. Here are some cases where it is not (these examples are extreme to drive the point home):

      1) What if I could sell you PV cells that cost 1% the $/Watt of traditional PV cells, but 1 acre of it only generated 100 Watts? Now you need an acre of land to power each 100 Watt light bulb.

      2) What if I could sell you PV cells that cost 1% the $/Watt of traditional PV cells without taking up that much space, but they required 10 times as much maintenance after they were installed, perhaps even needing to be replaced every year or 6 months? You going to pay someone to keep reinstalling it?

      3) What if I could sell you a bunch of super-cheap reflectors to focus the sunlight onto one tiny but expensive PV cell? If my parents, or possibly even my neighbors, had one of these when I was a pre-teen, I'll bet I would've been up on the roof with a big mirror or lens playing around with my nifty "fire ray", and I would not have been alone in trying that. And what about pine trees? I wouldn't want pine needles bursting into flame as they fall through the concentrator on my roof, so the concentrators would need some sort of enclosure, which limits their size, and thus their power.

      I might be able to come up with other scenarios if I give it more thought, but I think you get the point. The PV cell's $/Watt cost is not the only cost to consider.

  2. 60 is misleading by Harmonious+Botch · · Score: 5, Insightful

    It's power that matters, not current.
    The best solar cells today get about 13 watts / square foot. The toatl power available on a sunny day with near perpendicular light is 130-140 watts. So efficiency is near 10%. The best a new design can do is about 10-11 fold increase, not 60.

    1. Re:60 is misleading by anagama · · Score: 4, Insightful

      On second thought -- I think GP is right and my post is wrong. If a regular cell can extract 10% of the energy out of a 1 sq ft area, even an uber-crinkly cell couldn't get more than 100% of the energy that falls in that space, so a ten fold increase does seem to be the max. Perhaps we need a "think more" button next to the "preview" button.

      --
      What changed under Obama? Nothing Good
  3. Re:Better then 5x improvement not possible.... by Romancer · · Score: 5, Insightful

    You're talking about two different types of measurements for solar cells.

    The statement "60x the current" has almost no relation to the maximum theoretical conversion of sunlight efficiency. It completely leaves out the voltage problems inherrant in these 3d designs. The total output measured in watts or VA would be somehwat more comparable to your "20 percent efficient".

    Learn some math before you post.

    --


    ) Human Kind Vs Human Creation
    ) It'd be interesting to see how many humans would survive to serve us.
  4. Re:There's NO free lunch by Planesdragon · · Score: 5, Insightful

    If we had so many wind turbines that we were collecting enough power to run the world, would that not have some effect on the global wind patterns?

    No. There is simply more power in the Earth's wind than we could harvest. Or, if you please, the current annual input of power into the atmosphere is greater than the total energy cost of human civilization, by a few orders of magnitude.

    Remember: every single watt of solar power that reaches the ground winds up in the atmosphere as heat, the foundation of wind.

    Also solar power cools the Earth's surface. Solar farms are envisioned as acres and acres of panels in the desert. That would turn a very hot spot into a very cold spot, changing the currents there, and thus affecting overall temperature distribution (ie, the wind).

    If, and ONLY if, the solar panels were not only almost perfectly efficient, but also sucked energy from heat in the atmosphere.

    Same sort of thing goes for tidal energy. If you collect enough, you are going to affect life in the ocean.

    Tides are powered by the moon's gravity, bub. Sure you'll have an effect, but the tides are already affecting the moon's rotation.

    There just ain't no free ride.

    Depends on what you means as "free." Sure, the soup kitchen needs someone to pay for the soup, but the bums getting a hot meal get to enjoy someone else's largesse. Most of the power sources available to humanity work like that, including photovoltalic solar, fission, and hydroelectric.