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New Generator Boosts Wind Turbine Efficiency 50%

Posted by kdawson on Tue Nov 18, 2008 02:30 PM
from the reap-the-whirlwind dept.
MagnetDroid writes "A startup company based in Vancouver has developed a new kind of generator that could harvest much more energy from the wind. The design could not only lower the cost of wind turbines but increase their power output by 50 percent to as much as 100 percent, in some locations. Normally, when wind speeds drop, a turbine's engine becomes less efficient. The new engine, from ExRo Technologies, runs efficiently over a wider range of conditions. The design replaces a mechanical transmission with what amounts to an electronic one. Magnets attached to a rotating shaft create a current, but individual coils can be turned on and off electronically at different wind speeds." The company will begin field-testing a small, 5KW wind turbine by early next year.
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  • by MaxwellEdison (1368785) on Tuesday November 18 2008, @02:33PM (#25806557)
    Wind energy is a lot like politics and advertising. The more it blows, the more spin you see.
  • by cavis (1283146) on Tuesday November 18 2008, @02:41PM (#25806679)
    About a month ago, I was travelling on I-68/I-70 in Maryland, over the Cumberland Gap, when I saw a several wind turbines in the distance. After I got over the neat factor (even though we have them here in WV), I quickly realized that with each revolution of those turbines, we could/would be cleaning up the environment that much more. That alone makes me back this program 100%. Will it reduce foreign dependency as well? Let's hope so.

    But, we are all going to have to get over seeing them as ugly or migratory-bird killers for this program to work. I truly want a future where we use very little foreign energy, and we harness renewable energy sources. I say we get those new turbines into the wild as quickly as possible. T. Boone Pickens, get to work!
    • Re: (Score:3, Insightful)

      Will it reduce foreign dependency as well? Let's hope so.

      It won't. We depend on foreign oil and cheap labor. Windmills provide neither. The US has coal. Lots of coal. Lots and lots and lots of coal. In another couple of decades, it wouldn't be surprising to hear about the US being a fuel provider exporting coal to the world market. If we didn't invest in wind energy, we would just burn more coal.

      T. Boone Pickens, get to work!

      T Boone Pickens is a salesman. What do salesmen do? They sell things. Why do they sell things? To make a profit. Remember that. His willingness to invest in wind power is

      • Re: (Score:3, Insightful)

        T Boone Pickens is a salesman. What do salesmen do? They sell things. Why do they sell things? To make a profit. Remember that. His willingness to invest in wind power is admirable, but the natural gas plans he is pushing through along with wind will largely pad his wallet.

        Do you see an alternative in the heavy fright industry to natural gas? Mr. Picken's whole point is that you can't drive an 18 wheeler with electric (battery) technology. If you accept that then what do you purpose as a replacement for oil in this sector? And why assume that he is doing this just to 'pad his wallet'? He's already made his billions -- that and the fact that he's 80 years old (so I'm guessing he won't be running out of money before he dies) makes me think that he isn't purposing this just

          • by Shakrai (717556) on Tuesday November 18 2008, @03:55PM (#25807965) Journal

            There's tons of oil still untapped in the world.

            How is that going to work out when we use one quarter of the oil on this rock? Do we have one quarter of the oil reserves?

            If we could just cut out the politics and the environmentalist bullshit, we'd be a lot better off.

            Cut out the "environmentalist bullshit" and you are still left with the cold reality that we are sending $700,000,000,000 out of this country every year to pay for our oil addiction. Much of that money goes to countries that don't particularly like us very much. What do you suppose would happen if we invested that money into domestic energy sources like wind and natural gas? Job creation and economic growth perhaps? This is a national security issue in addition to being an environmental one.

    • by Chris Burke (6130) on Tuesday November 18 2008, @02:57PM (#25806979) Homepage

      But, we are all going to have to get over seeing them as ugly or migratory-bird killers for this program to work.

      And to do my part, I'll point out as I do in most wind turbine threads that windmills are not significant bird killers any more. In fact the very worst wind farm ever, Altamont Pass, killed fewer birds per year than a typical 3-story office building. And that was combining multiple worst-case factors, like an outdated scaffold design that encouraged raptors to nest on them, smaller fast-moving blades that are proven to be more difficult for birds to see and avoid, and a highly disadvantageous location in a choke point for bird migrations.

      Modern wind mills have monolithic poles with rounded tops that birds can't nest or sit on, and have much larger, slower moving blades* that birds can see and avoid. I believe now they also do some cursory environmental studies to make sure they aren't putting the windmills directly in bird migratory paths, but with the other two improvements this probably isn't even that big a deal.

      I'm a bird nerd. I love birds. If you can accept the bird deaths caused by glass windows in cities, windmills are not an issue.

      Oh, and I think they're rather beautiful. :)

      *Largely for efficiency reasons, the bigger the blade the more efficient. IIRC, the way they choose the sizes for windmill blades these days is by what will fit on the largest legally allowed trailer. I've seen convoys of trucks, each with very long trailers, each carrying *one* blade.

    • Re: (Score:3, Informative)

      They kill more bats than birds, as an fyi. And the birds they do get are mostly local low flying species- most (not all) migrants tend to fly high. The interesting thing is that most of the animals aren't killed by impacts, but by massive internal bleeding from decompression as they get caught in the low pressure zone behind the blade.

      Actually, I think I might have read that in a link off /. Or possibly BiologyNews.net

      I like windmills, but I think there has to be some way to mitigate the danger they pose t

    • Will it reduce foreign dependency as well? Let's hope so.
       
      No, because our main issue is with transportation fuels of which there is no substitute for the lighter grades of crude oil.

    • by Lord Ender (156273) on Tuesday November 18 2008, @05:08PM (#25809127) Homepage

      Do any actual humans seriously give a shit about migratory birds flying into windmills? That sounds like the sort of BS an internet troll might bring up. If someone told me that in face-to-face conversation, I would probably just stare at him as if he had said his goldfish commands him to sing it lullabies in falsetto every night, lest it destroy the universe.

  • Nice work! (Score:4, Insightful)

    by girlintraining (1395911) on Tuesday November 18 2008, @02:41PM (#25806683)

    So let me get this straight -- it's more efficient, has fewer moving parts, has a higher power output, and is cheaper to mass produce? Buy that engineer a beer! This is a real leap forward in a machine class that hasn't made more than incremental improvements for awhile now. The spirit of Nikoli Tesla approves. Next question: Can this technology be adapted for use in the hydroelectric industry? I think it may be possible, and it would reduce maintenance costs somewhat -- maybe we could throw out the sluce gates and make water flow through the dam with fewer electromechanical parts?

    • According to the company's website [exro.com], which does have pictures of the design for anyone who is interested, this could be used with other energy sources than wind:

      While this overview focuses primarily on the wind applications, VIEG Technology is expected to have a material impact on the economic viability of a wide range of renewable energy applications.

      There you go. I predict this could be more applicable in tidal energy than traditional big-dam hydro, although it might be useful in small, run-of-the-river projects to make them more efficient. They might even be useful in big run-of-the-river projects [plutonic.ca], which will create over 1,000 megawatts of new electricity in the next few years in British Columbia alone.

    • Re: (Score:3, Insightful)

      Can this technology be adapted for use in the hydroelectric industry?

      It would depend on whether the water flow was constant or not. If the water flow in a hydro generator is constant, than no. If not, then yes.

      • Re:Nice work! (Score:5, Insightful)

        by Firethorn (177587) on Tuesday November 18 2008, @04:21PM (#25808365) Homepage Journal

        unless the place is not very good for windmills in the first place.

        substitute 'sub-optimal' for 'not very good' and you're looking at the difference between economical and uneconomical for millions of acres of land.

        As is, from the maps I've seen, less than 1% of the area of the USA could be considered 'optimal' areas for turbines. Not really scattered either, mostly in a few spots. Right now you need very steady winds, within ~10mph to be really efficient. If the wind is too fast you have to shut down the turbine, same with too slow.

        US wind map [windpoweringamerica.gov]. Going by this, you can see that there's a very limited amount of area, mostly offshore, rated 'Superb'. If this turbine makes the red outstanding areas equivalent to superb, that more than triples the area. If it makes 'good' viable, that enables large chunks of the midwest.

        Perhaps most importantly, it'll help reduce the low production periods.

  • I wonder... (Score:5, Interesting)

    by michrech (468134) on Tuesday November 18 2008, @02:42PM (#25806697)

    ...how something like a CVT would work for a wind turbine.

      • Re: (Score:3, Informative)

        been there, done that, as have *countless* others. Really, I don't know how this even begins to classify as 'new'.

        Automatic star-delta switches have been done, same with electronic versions that do voltage conversion so that the maximum amount of power flows to the grid (or the batteries for off-grid systems).

        Wind power is *full* of snake oil companies and investor scams. As well as people that try to pass off old stuff as new.
         

  • by schwaang (667808) on Tuesday November 18 2008, @03:04PM (#25807113)

    The first thing I wondered was "what makes this design different?"

    Magnets attached to a rotating shaft create a current, but individual coils can be turned on and off electronically at different wind speeds.

    This is a nice, simple explanation of why this design can be kept efficient in a wider range of wind speeds.

    Since we love to bash some of the lamer summaries, I think this one deserves a bump on the plus side.

  • Good concept... (Score:4, Interesting)

    by Manip (656104) on Tuesday November 18 2008, @03:21PM (#25807385)

    So what of the things that rarely fails me is a "common sense" check on new designs, particularly when it comes to renewable energy concepts (as there are a lot of impossible inventions around).

    So let's break down this design:
    - Works like a normal electric motor so thus we know it works *CHECK*
    - Have electronic switches to open and close a circuit, which we know works *CHECK*
    - We know longer circuits have more resistance than shorter ones *CHECK*
    - We know changing the number of coils in an electric generator is optimal for different levels of generation *CHECK*

    So it seems to be a very good design that should work very well. Their claims of 100% more efficiency are a little over the top but may work in some locations. I think it is safe to say that most locations should see an increase in efficiency with the new design over the old one.

    The way they've built their motor is also a little novel but only really amounts to a way to customize the motor for different situations and thus really isn't all too interesting in the grand scheme of things.

  • by notgm (1069012) on Tuesday November 18 2008, @03:47PM (#25807843)

    am i the only one worried that with a boom in windfarms, the drag on the earth's rotation will increase, slowing it and lengthening the day, making me stay at work *that* much longer?

  • by Sockatume (732728) on Tuesday November 18 2008, @03:54PM (#25807941) Homepage
    Wind turbines do not work that way.
    • by Anonymous Coward on Tuesday November 18 2008, @02:39PM (#25806647)

      Since when is an increase of efficiency by 100% impossible?

      For arguments sake, let's say that current wind turbines are 10% efficient. This new turbine is therefore 15% to 20% efficient.

      But will this make home wind turbines effective purchases? I doubt it.

      I hope the design can be retrofitted into existing turbines, since there are so many deployed now.

    • No.

      The generator is more efficient in changing wind conditions. When the wind is faster, it turns on more coils to provide greater mechanical resistance and takes more energy out of the wind. When the wind is slower, the turbine can still run because the generator can be switched to take less energy out of the wind.

      This isn't a consideration for regular power plants because the amount of energy sent to the turbine is well-controlled and doesn't vary with time like wind speed does.

    • by Chris Burke (6130) on Tuesday November 18 2008, @02:41PM (#25806673) Homepage

      "The design could not only lower the cost of wind turbines but increase their power output by 50 percent to as much as 100 percent, in some locations."

      100%? Why stop there?!

      Because, due to this having not a damn fucking thing to do with perpetual motion or snide remarks regarding such, there's only so much energy that can be extracted from the wind. Getting a 1.5x to 2x boost -- over the course of a year, meaning combining periods where the windmill was operating efficiently, and those times where it was not -- is great. I don't know why you phrased your question the way you did.

      Oh, and, uh.. why is this whole article about windmills? Couldn't these improvements in generator efficiency be used across the board?

      Not really. The majority of turbine generators are designed to operate at a single, optimal frequency. Wind however is by its nature variable, so to get peak efficiency across various RPMs requires some extra ingenuity. Maybe this could be applied to your car's alternator, I don't know.

        • by Chris Burke (6130) on Tuesday November 18 2008, @03:53PM (#25807919) Homepage

          Just out of curiousity, and I haven't RTFA yet so maybe the answer is there, but couldn't you vary the pitch of the vanes on the turbine to maintain a constant RPM in varying wind conditions, much the way a constant speed propeller on an airplane works?

          They do that too, even on existing windmills. The problem is that when the wind speed is low, there's nothing you can do to make it go fast, so if you wanted to maintain constant RPM in the generator, you'd have to pitch the blades to give very low speed in high winds, which is rather counter-productive. Adjusting the resistance of the generator so it works across a wider band of RPMs, combined with adjusting blade pitch, provides much better results.

    • by Martin Blank (154261) on Tuesday November 18 2008, @02:41PM (#25806685) Journal

      TFA doesn't mention specific percentage improvements in efficiency. That was kdawson's contribution, and then only in the poorly-worded headline. TFA is claiming that the overall output of a given wind turbine could be boosted by 50% or more by altering the dynamics of the generator to make it more efficient over a wider range of wind speeds.

      Basically, turbines are most efficient at a given speed, and efficiency drops off for anything outside of that, whether faster or slower. This new design attempts to address that by decreasing the amount by which the efficiency drops off at different speeds. The improvement in the efficiency curve boosts overall power output, as the turbine isn't as strictly limited to a given wind speed for peak efficiency as it was before.

      • Re: (Score:3, Informative)

        That's called maximum power point tracking and is pretty old in concept and in actual use today in many thousands of wind and / or solar installations.

    • Re: (Score:3, Interesting)

      Ever read summaries? Most power generation is able to work with reasonably constant RPM's. Windmills don't have that luxury, so often are working at RPM's that are not optimum. This method (if it works) widens the optimum range.
      • by MozeeToby (1163751) on Tuesday November 18 2008, @03:52PM (#25807913)

        Windmills don't have that luxury, so often are working at RPM's that are not optimum. This method (if it works) widens the optimum range.

        Close but not quite what they're getting at. What they're doing is increasing/decreasing the resistance to keep the windmill in the optimum RPM range over a larger range of wind speeds. So at 5 mph, the blades might spin at 20 rpm and generate 2 MW. At 15 mph, with the new system the blades still spin at 20 rpm, but now generate 5 MW. As oposed to traditional generators, where it would be spinning at 30 rpm and only generating 3 MW.

    • That's 100% of the maximum possible output of the generator. Not 100% of the energy that comes into it being converted into electricity.

      The words, they MEAN things.

    • Re: (Score:3, Informative)

      A 100% improvement in something just means it has been improved by a factor equal to what it can already do. In other words, it's twice as efficient. If you can't understand that then you might want to think twice before posting on /. /just sayin'
    • If 1 wind turbine can output 1MW. Increasing that to 2MW would be 100% more output. It can still only be 10% efficient, but the output has doubled. 50% more efficient would be 1.5MW. Heck it could be possible to get up to 1000% more efficient (10MW), and still be at under 50% efficiency.

      Maths, don't leave home with out it.

    • "It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt."

      Just like most of the energy contained in a gallon of gasoline is not converted into forward motion, most of the energy passing by a wind turbine is not converted into electricity. It's the "low hanging fruit" in energy research. It sounds like their idea is to use more but smaller and more efficient generators that are adapted to input from variable wind speeds rather than constant input from a

      • by mr_mischief (456295) on Tuesday November 18 2008, @03:28PM (#25807493) Journal

        It's kind of like a transmission. It's actually also kind of like the reverse of the adjustable displacement engines in some vehicles.

        In some cars, you have an 8-cylinder engine but can use 4, 6, or 8 cylinders at various times based on the amount of power you need to generate. It doesn't take 8 5 liters of displacement to maintain highway speeds, but getting up to them quickly may. Turning off cylinders not in use saves fuel by not burning it when it's not needed. Each cylinder only draws chemical energy to make kinetic energy as needed.

        If you left all the coils engaged, you might have too much resistance to generate any electricity in light winds and too much to generate it efficiently in more moderate winds. Yet if you build a turbine specifically for only light or moderate winds, you don't get any additional power once it is maxed out.

        This solution uses wind, but you can't just press down on a pedal and ask for more wind (well, you could ask, but you'd be disappointed most of the time). So what it does instead is it has a magnet-in-coil generator with separately activated coils. Each coil only draws mechanical energy to make electricity as the mechanical energy is available. The rest of the coils are left as open circuits. If there's enough wind to turn the blades with half the coils on but not all of them (or too slowly to make sense with all of them), then you just open the circuits on half the coils and the other half keep generating. Only the coils in a closed circuit generate current and present meaningful resistance to the turbine. As you have more wind, you generate more power up to the maximum. The maximum number of coils doesn't impede this turbine from generating less current when some wind is still available though, because it just disconnects the spare coils until they are needed.

    • Re:PICS OR GTFO (Score:4, Informative)

      by philspear (1142299) on Tuesday November 18 2008, @03:10PM (#25807195)

      Right, because pictures are proof. Just like the phantom console, which had pictures (http://gamedeveloper.digitalmedianet.com/articles/viewarticle.jsp?id=19801) and is totally real right now. In fact, I'm playing the invisible version as I'm typing this!

    • Re:PICS OR GTFO (Score:5, Interesting)

      by jacquesm (154384) <j AT ww DOT com> on Tuesday November 18 2008, @03:12PM (#25807229) Homepage

      He has a point, even if 'pics' won't make much difference the vapourware will stick. There is this thing called Betz' law and it is pretty specific about how much energy you can extract from any moving medium.

    • I've used hydraulics. The efficiency is rather poor (remember in a wind turbine the hoses have to rotate or you need a rotating pressure joint - the thing has to face the wind, and to get good output the prop center needs to be high up meaning long hose runs.) I find it very hard indeed to believe that a PM generator with adaptive electronic control needs more maintenance than hydraulic systems, or that any cost savings outweigh the loss of efficiency over a 20 year plus lifespan. As a simple example, rail
    • Re: (Score:3, Interesting)

      I'd love to see some source on this.

      I understand that a hydraulic pump and hydraulic motor coupled with two lines would be modestly simple, but the repairman going out to fix the system will probably have the same hourly/salaried rate as the repairman going out to fix the generator. Windmills have been modestly simple for hundreds of years, though. Today, the power chain looks like this:

      Wind --> Blades --> Shaft --> Gearing --> Generator --> Grid

      With this new system, they're hoping to
    • I haven't done anything to work this out, but I do think the effect is negligible. Most of these turbines are 200-250' tall - so on the order of a 20-30 story building. We build those all the time, without worrying about affecting weather patterns (though they may have a very local effect). But the turbines are much less disruptive to the wind than the building even - they just slow it down a bit, rather than blocking it all together. So, other than causing storms to more often go around the wind farm i
    • by Gibbs-Duhem (1058152) on Tuesday November 18 2008, @03:48PM (#25807853)

      Yes, it does have an effect. There is data showing that in wind farms the average temperature is slightly higher, and of course the wind speed is lower.

      Very large wind farms will probably cause local temperature increases of 1-2 degrees centigrade. This could, of course, be mitigated by planting lots of trees all around them...

    • by queequeg1 (180099) on Tuesday November 18 2008, @04:14PM (#25808237)

      I'm not sure if you're being sarcastic or not. There was recently an article in the local Portland, OR news about how the windfarms that have been installed in the Columbia River Basin may actually have a detrimental impact on salmon. Apparently, some parts of the electrical grid in this part of the country are operating near peak capacity. When the wind really kicks in and pushes the grid to its limits, other parts have to lower production. In our case, this means letting a lot more water spill over the dams. This, in turn, tends to introduce way too much nitrogen into the water, which harms the fishies. Or so goes the theory.

    • Whoever added the tag has no clue. This IS a generator.

      It generates. So loosely speaking it's a generator.

      But there is a terminology distinction when you get into TYPES of things that generate. They all have coils and a field in relative motion to create the output voltage. But a "generator" creates the field with electromagnets (generally using more coils driven by an external electrical source, a side-effect of the current in the output coils, or otherwise by pulling power from the input shaft) as oppo