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New Generator Boosts Wind Turbine Efficiency 50%
Posted by
kdawson
on Tue Nov 18, 2008 03:30 PM
from the reap-the-whirlwind dept.
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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Same ole, same ole... (Score:5, Funny)
Even less dependency on foreign oil (Score:4, Insightful)
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:Even less dependency on foreign oil (Score:5, Informative)
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 And that was combining multiple worst-case factors, like an outdated scaffold design that encouraged raptors to nest on them, smaller fast-moving blades that are proven to be more difficult for birds to see and avoid, and a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.
Parent
Re:Even less dependency on foreign oil (Score:5, Funny)
"In fact the very worst wind farm ever, Altamont Pass, killed fewer birds per year than a typical 3-story office building."
Wow, just think of the bird killing machine we could make if we mounted these windmills on 3-story buildings. I for one welcome less poop on my Humvee. ~
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Re:Even less dependency on foreign oil (Score:4, Informative)
Spot on. The 'windmills kill birds' argument is just another way for the 'we're against everything' crowd to try to stop any kind of change, for better or worse.
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Re:Even less dependency on foreign oil (Score:5, Funny)
he 'windmills kill birds' argument is just another way for the 'we're against everything' crowd to try to stop any kind of change
Build absolutely nothing anywhere near anything
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Re:Even less dependency on foreign oil (Score:5, Funny)
We need to explore the effects/affects of what we do.
I agree. It's/its important not/knot to/two/too lose/loose sight/site of our/hour responsibility.
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Re:Even less dependency on foreign oil (Score:5, Insightful)
If the alternative is coal plants, then windmills are far less deadly to birds than the added carcinogens. A few extra dead birds hitting turbines can be easily replaced in the biosphere. Coal smoke is a more widespread problem.
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Re:Even less dependency on foreign oil (Score:5, Funny)
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.
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Re:Even less dependency on foreign oil (Score:5, Insightful)
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.
Parent
Nice work! (Score:4, Insightful)
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?
Other applications (Score:4, Informative)
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.
Parent
Re:Nice work! (Score:5, Insightful)
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.
Parent
I wonder... (Score:5, Interesting)
...how something like a CVT would work for a wind turbine.
Decent Summary, Thanks (Score:5, Interesting)
The first thing I wondered was "what makes this design different?"
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.
Re:This perpetual motion machine just keeps gettin (Score:5, Insightful)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Insightful)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Insightful)
"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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Insightful)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Informative)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Insightful)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Informative)
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.
Parent
Re:This perpetual motion machine just keeps gettin (Score:5, Informative)
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.
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Re:PICS OR GTFO (Score:4, Informative)
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!
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Re:PICS OR GTFO (Score:5, Interesting)
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.
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