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If You Just Loved The Solyndra Technology...

August 28, 2012, 8:43 am

...you will love this too.  Solyndra used cylindrical solar cells nested inside a u-shaped mirror to concentrate sunlight to get more power per square inch of solar cell.  The problem is that all that extra shaping and mirrors added cost, and only made sense if solar cells were expensive.  After all, if solar cells are cheap, if one wants 20% more output, it's easier to just increase the solar cell area by 20% than to add all the concentrator rigmarole.

Well, dreams die hard, and here is the latest idea -- spherical concentrators.  These things have huge spheres and tracking motors, all for a 35% increase in efficiency.  Methinks that just adding 35% more PV cell area is going to be cheaper, but this could well be yet another flytrap for Obama Administration officials, who are to sexy-looking new technologies like a degenerate wagerer at the track is to a hot tip.

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Category: Energy
  • a_random_guy

    Wow. My immediate reaction - entirely aside from the obvious cost of creating these enormous lenses - is heat. That lense is enormous, and it is focusing light on a solar cell sitting naked in the air. Without some very serious cooling, that solar cell will be charred wreckage in a few seconds.

    In the article itself, there is only one photo showing the device in real operation. You can see the light shining *through* the solar cell. Take a close look at the lense: it is almost entirely covered in foil, allowing light to shine through only a very small hole.

    So: we not only have the huge lenses, and the tracking system. We are also missing the massive cooling system that will have to be mounted on the assembly. It's going to required forced liquid cooling, including some pretty high-powered pumps. That should more than compensate for their 35% increase in efficiency...

  • Samsam von Virginia

    8.3 pounds per gallon of water.
    What anti-freeze are they using that doesn't (further) harm optical properties? I suppose alcohol might work in a sealed system.
    Chromatic aberration may be a problem because the focal length is so short (some colors in the spectrum might miss the target or require a larger target than would otherwise be needed).
    Sunlight + water => algae. But maybe not in a sealed system.

  • http://thegameiam.wordpress.com David

    So it will be inefficient, overpriced, and overheated, but will look cool? That sounds like a perfect metaphor for the current administration...

  • patrick

    The marketability of a photovoltaic cell is generally a bathtub tub of it's space efficiency (i.e. energy output per square foot). There are uses for the least efficient because they're the cheapest, as well as for the most efficient because there are a lot of space-bound applications. As long as the cell is efficient enough heat won't be an issue (2nd law of thermodynamics - all the energy going into electricity can't be making things hot), and if the technology is at the point where it can keep cool at higher light output than natural sun will ever do it may have a niche.

    That said, the government shouldn't be blowing money on it and if there's ever an economically feasible solar solution it'll probably be more along the lines of the molten-salt plants going into production now.

  • Mark

    Maybe not related to this specific thread, but I laugh at the greenies who thing that "green energy" is needed because of "Climate Change", but now are seeking to put tarrifs on the importation of solar panels to protect themselves. If GREEN is really because of the catastrophic problems of climate change we should be interested in importing the cheapest solar panels to convert energy production away from carbon based energy. Instead, we will have protectionism!!!!!!!!!!!!
    This is the "green energy" equivalent to rich greenies flying around the globe in their private jets.

  • Nehemiah

    If it doesn't work out they can sell them to large Gypsies as crystal balls.

  • Don

    Warren, there is one thing you're not thinking of I think. The real justification for concentration is that they increase the amount of voltage more quickly in the cell. As with any semiconductor device, there is a threshold voltage below which the semiconductor simply doesn't operate. For the most part, that .6 volts for silicon-based semis. By concentrating the light, you get to that .6 more quickly, meaning you produce power for more hours of the day (which is the whole game for these sorts of systems). Also, as better panels are created (from current 17% to the new 22% and up to the 35% efficient technologies in labs today), its relatively easy to replace 1 than to replace 2 or 4 or 10 of them (and the are smaller, based on the photo), making upgrading a lot cheaper.

    Now, all that said, the silicon based panels on the market today SUCK, and are not technologically or economically ready for general power production even with concentrators. When we get the 30+% panels out, then it might make since. Also, all the fancy technologies (Solyndra or this one) are mostly flashy, trendy pretenders to the tried and try fresnel lenses which are cheap to produce in almost an size and quantity.

    And motorized tracking is just plain stupid from an reliability point of view (unless you can tie this thing to a sun flower). You DON"T want moving parts in something like this, especially when if you plan on deploying acres of them in the middle of the desert.

  • http://www.facebook.com/matthew.slyfield Matthew Slyfield

    Based on the pictures, tracking is only done by moving the solar panel relative to the ball lens. The lens itself is stationary. This would be more reliable, less prone to failure and use less energy than adding tracking to a standard flat or concave solar panel. The picture with the foil wraped ball apears to me to go with the photo below it which is captioned as a test of generating power from moonlight, a neat trick if the ball lens concentrator is that effective.

  • Mark2

    It won't need cooling because all that solar goodness will be converted directly to electrical energy :P

  • Ted Rado

    Solar and wind energy are limited by the intermittent naure of the energy source. This requires standby and/or storage. As has been pointed out repeatedly, even if the cost was competitive for the solar/wind power itself, the cost and problems of backup/storage would sink the idea. Until a COMPLETE plan is in place, beating one segment of it to deathe is a waste of time. Thise seeking USG money for their projects should be required to submit such a total plan.

  • http://twitter.com/EHUSMAN EHUSMAN

    He's using triple junction cells. A simple heat sink will be sufficient. Concentration rations of 500:1 with a simple aluminum heat sink are not unknown.

  • http://twitter.com/EHUSMAN EHUSMAN

    More like 2.5 V for these TJ cells. The tracking is not there primarily to get the voltage up: it's there primarily because concentration requires a lens which must be pointed at the sun. This is quite clever, but ultimately not as inexpensive as the fresnel lenses as you point out. Does the smaller motor drive make up for the difference in price? Possibly, but I doubt it.

  • mesocyclone

    Man... that looks like an ugly piece of what goes for art these days.

  • http://twitter.com/EHUSMAN EHUSMAN

    Amen. If we must have cheap solar to protect us from climate change (or whatever), then why should we care who makes them?

  • http://twitter.com/EHUSMAN EHUSMAN

    CA is a concern. The weight - not so much since that part isn't being moved.

  • obloodyhell

    This whole idea is just utterly ephtarded. You don't decrease your coverage requirements, you're just adding another layer of materials to make a small decrease in the solar cell demand. And I'm not buying that this highly breakable concentrator is all that much cheaper than 20% more solar cells even at high prices.

  • obloodyhell

    Ted, how diffuse it is is also highly relevant. Deriving power from energy requires energy gradients in all forms of power production... but solar power (as with wind) provide very small gradients to work with, leading to remarkably bad efficiencies. Add those two together and you have an even worse problem.

  • obloodyhell

    }}} You DON"T want moving parts in something like this, especially when if
    you plan on deploying acres of them in the middle of the desert

    AH, well, THERE is your problem. They don't actually plan to deploy acres of them in the desert. They want dumbsh** investors to THINK that's the plan.

    The real plan is to suck at the public teat for a while, pocket the money, and then declare bankruptcy.

    Like... DUH.

    The chief reason it may be profitable is that public teat of enforced citizen-investors, who can't say "What? You want me to give you money for WHAT? LOLOLOL...Do I *LOOK* stupid to you? Eph off!", and instead get stuck putting their money into this ephwit retarded boondoggle.

    That, by the way, is the term for this. There should be a picture of it in the dictionary and encyclopedia in the entries for "boondoggle"

  • mark2

    One way to counter the naure of intermittent power is to change habits based on availability. I don't know if we are that point yet corporate wise, but if you do your most significant work from 11 - 1pm (when solar is peak) and cut back at other times - cut back on usage, or even send folks home on low power days are things that can be used to help compensate.
    In CA we already do this to some extent with our power alerts. On Power Alert days some companies voluntarily cut back on power use. Usually grocery stores turn off half the lights and set the thermometer up 2 degrees.
    Eh there are ways. If solar was all that I had, I would figure out how to use it to my advantage.

  • Ted Rado

    Mark2:
    Many activities must run 24/7. Heavy industry, for example. Many activities already adapt to the sun. Farming is an example. Many leisure time activities as well adapt to the sun (going to the beach, outdoor sports, etc.). I cannot imagine the manager of a factory calling all his employees and telling them that the sun is shining (or wind blowing) so lets crank up the production line. The time to start up and shut down production is usually much longer than the swings in wind and solar. On partly cloudy days, the power would go on and off every time a cloud passed in front of the sun.
    I imagine that in th old days, winfmills to gring grain were run when the wind blew because there was no alternative.

  • DC

    That's not the only spherical solar concentration project around; http://www.rehnu.com/, housed at UA, is working on more or less the same principle. And yes, you need a large tracking structure and deal with the heat on the solar cells. Why more research money doesn't go toward cheaper and more practical alternatives in nuclear reactors (e.g. Toshiba's modular reactor offering, or Bussard's electrostatic-confinement fusion, or even LFTRs) is beyond me!

  • rxc

    So you want to change people's "habits" to meet a "social goal". This is a standard progressive technique to make consumption of goods and services more "efficient", by driving down demand - consume less, plan when you will consume it, etc. Use public transportation with fixed schedules instead of automobiles with the freedom to go when you want, and where you want to go.

    On the supply side, we have the progressive technique of decreasing the efficiency of production of the same goods. Use union labor that comes with all sorts of complicated rules, add more rules from governments for health and safety and environmental reasons, affirmative action, all sorts of social justice and social engineering purposes, use the least efficient methods of generating energy, all supposedly to advance a social purpose, but the results is really just increasing price, so that consumption is pushed down even further.

    It is called totalitarianism. Control.

  • obloodyhell

    }}}} This is a standard progressive technique to make consumption of goods and services more "efficient", by driving down demand

    Indeed.

    Civilization Law #1:
    Civilization advances by increasing the number of important things you can do without thinking about them.

    This is a truly profound description of what it is that makes for true Progress.

    Some actions may be necessary but they are not Progress unless they meet the criteria specified above.

    Indoor plumbing? Progress. Cars? Progress. Mass Transit? Most, not Progress (though, at least in some environments, necessary). Ball point pens? Progress.

    Changing your habits to match when power is available? most emphatically NOT Progress. And this is "Like, Duh?" obvious: If you have to add thinking about what the power availability is to your planning of your time, you're adding an extra step and complication to those plans. There will be opportunity costs as a result.

    }}}} Eh there are ways. If solar was all that I had, I would figure out how to use it to my advantage.

    Not that likely, See above. If there was a way that it WAS a true, consistent improvement, someone most likely would have figured out a way already. It's not like it hasn't been around for decades giving BILLIONS the opportunity to think on it.

    If it was the ONLY way, then yes, we'd ALL make the best of it. Thankfully, it's not. And the smart ones among us grasp the most important part of that statement is "it's not", and are determined to keep it that way.

  • obloodyhell

    Shucks, didn't last long. :-P Use the screencap. Feel free to forward it.

    Crossposting this:
    ========================
    BTW, another thing in support of the "boondoggle" idea -- realize what SOLAR THERMAL is -- it's using a more conventional power generation design to produce the electricity. Instead of coal or oil or NG or nuclear or what have you, it uses concentrated HEAT from the sun -- produced using mirrors -- to generate power.

    In short, it already does this -- "concentrate" the solar power -- in order to produce the power it produces as a system. And it applies conventional conversion systems, which are FAR MORE EFFICIENT than solar cells, and currently could even be set up to approach the current experimental maximums of around 65%... Lonny Johnson's experimental JTEC could easily get 50% from this, since it's source-independent, and that's right out of the box.

    So there's no way this giant pile o' crap is going to do ANYTHING but line the pockets of some quacks and charlatans who know what a load of crap it is, and are nothing but con artists looking to fleece their investors and, they hope, the idiots in the "Federal Green Energy Grant" system.

  • richard

    It also only works if the sun is shining directly on the lens. During a clouded day the lens has no added value.

  • http://twitter.com/netbacker netbacker

    I thought the biggest benefit of Solyndra was with its cylindrical cells it used less surface area and that made it easier to mount on any kind of rooftop. Even in areas that had high winds. Mounting traditional solar panels in such places needed a lot of additional rooftop reinforcements and most old structures wouldn't meet the requirements.
    Anyways they are done now.