Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Power Earth Technology

New Generator Boosts Wind Turbine Efficiency 50% 315

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.
This discussion has been archived. No new comments can be posted.

New Generator Boosts Wind Turbine Efficiency 50%

Comments Filter:
  • 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)

      by RingDev ( 879105 )

      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

      • We already do export coal to the world market. Lots and lots of coal.
      • Re: (Score:3, Insightful)

        Comment removed based on user account deletion
      • I don't have a real problem with wind power, but it takes a lot of them to replace a coal plant. Depending on who's doing the figuring, the number of wind turbines changes. 1395 1.65MW wind turbines to replace the largest coal plant in Wisconsin for name plate production. Newer wind turbines to replace older coal plants isn't that bad of deal though.

    • 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)

      by turtledawn ( 149719 )

      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

      • Would a cage around the blade path, like the ones we have on home floor fans, be a potential answer? It doesn't have to be closely spaced, you're not trying to keep out kid's fingers after all, but it would need to be sturdy enough to withstand moderate hail storms.

        It wouldn't be effective at all. Modern wind turbines have a diameter of 40-90 metres. A wire cage, sturdy enough to block bird and bat entry, survive hail and storm, would block off a significant portion of the wind. You would probably get
    • 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.

    • Comment removed based on user account deletion
    • by bwcbwc ( 601780 )

      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.

      Better yet, lets work on some turbine designs that don't involve large blades sweeping through the air. With this "transmission" design, it should be possible to build some wind generators that can work efficiently without requiring the amount of torque that is needed to make the current desig

    • Ugly? If I owned a farm or some such I'd love to have a few turbines on them. I think they look fucking awesome and besides, what kind of person would I be if I advocated looks over environmental consideration?
    • 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?

    • by bwcbwc ( 601780 )

      WOOT! Assuming it isn't just BS to get VC funding. The theory sounds reasonable, though.

    • Other applications (Score:4, Informative)

      by Jabbrwokk ( 1015725 ) <grant...j...warkentin@@@gmail...com> on Tuesday November 18, 2008 @03:01PM (#25807047) Homepage Journal

      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.

      • I think it's an adaptation of certain kinds of motor drives that have already been in use for some time, where changing the "gear" means changing which taps are powered on the motor.

    • Re: (Score:3, Insightful)

      by mcgrew ( 92797 ) *

      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.

    • by jhol13 ( 1087781 )

      Hydroelectric turbines are already extremely efficient (over 80% if not 90%), there cannot be much improvements any more. Besides they are completely different.

      For the wind turbines ... I suspect this is apples to oranges comparision. Getting 100% power increase on low wind is not going to make big difference on a site when yearly output is calculated - unless the place is not very good for windmills in the first place.

      After all the energy of the wind is proportional to the cube of the speed.

      You should stil

      • 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.

    • 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!

      Yeah...right after you have a full scale working prototype.

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

      No point in that. This thing (if it works) makes the generator work more efficiently over a wider range of excitation by varying resistance. Hydro generators run optimally at a single point and they can already control that with water flow. The only benefit this thing has is for sources where your input energy varies.

    • Re: (Score:2, Informative)

      by x1n933k ( 966581 )

      Indeed, I think we've had this sort of thing for a while in Record players, they call it Direct Drive. http://en.wikipedia.org/wiki/Technics_SL-1200 [wikipedia.org]

  • 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.

    • by lupine ( 100665 ) *

      Individual coils on the generator can be activated as needed. It doesnt need a transmission, that's the whole point.

      What you should be asking is: Would this design work in electric car motors? The Tesla currently uses a 2 speed transmission. How much extra would they pay for a motor that doesn't need any transmission(or only needed a simple gear reduction)? Would it improve engine efficiency or regenerative braking efficiency so that they wouldn't need such a costly battery pack?

      Future electric car dealers

      • Re: (Score:3, Informative)

        by jacquesm ( 154384 )

        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.
         

    • Re: (Score:2, Insightful)

      by Cyner ( 267154 )

      The biggest problem with CVT technology is that currently it's pretty weak. CVTs in cars can only handle about 300HP (~230KW); a 5KW+ turbine would snap that like a matchstick. And one big enough to handle that turbine would sap quite a bit of efficiency.

      • 5kW is 6.7HP, so why would a CVT sized for 300HP "snap that like a matchstick"?

        Did you mean 5MW?

  • 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.

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

    • 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

  • by Anonymous Coward

    somebody is telling a stretcher here. Power goes as the cube of the wind speed. There's no point in trying to squeeze a few more percent at the low end of the range. There's just no power down there to squeeze out.

    for example, at 1/2 top speed, you're getting 1/8 or 12.5% of full power at best. If it's actually 8% due to slow generator speed, no big deal. Another 4% is not worth spending much on.

    • Re: (Score:2, Insightful)

      by tristanreid ( 182859 )

      What if the wind blows at X 80% of the time, and gusts above X 20% of the time?

      You're assuming that they're trying to squeeze more energy from the low end of the range, I think they're actually trying to catch the period gusts that are above the normal range. Increasing the resistance will make the windmill safer (and more effective) to operate at higher speeds, until a certain limit is reached where it just has to be shut down for safety.

      -t.

    • With magnetos the voltage goes up with the RPM. In a simple direct drive mill with no pitch adjustment the RPM (for a given efficiency) goes with the wind speed. Operating above the ideal RPM cuts your torque, too far below it also looses you torque by causing the blades to go into aerodynamic stall.

      In a battery charging application there is no current, and no load torque, on the blades until the RPM is high enough that the voltage from the genny is above "cutin", the sum of the battery voltage and the di

  • 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.

  • OK, a little off topic here, but question for anyone who can actually answer knowledgeably:

    If the wind is turning these turbines, it's obviously taking some energy out of the wind. If wind farms become massively deployed, couldn't that change weather patterns as we alter wind energies? Or, is the difference so negligible that the amount of turbines constructed for our energy needs would only be a fraction of what is necessary to cause such a disruption?

    Not that I'm against wind energy, mind you. However,
    • Re: (Score:3, Insightful)

      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 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)
    Wind turbines do not work that way.

In practice, failures in system development, like unemployment in Russia, happens a lot despite official propaganda to the contrary. -- Paul Licker

Working...