Slashdot Mirror
New Generator Boosts Wind Turbine Efficiency 50%
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.
Wind energy is a lot like politics and advertising. The more it blows, the more spin you see.
-=Bang Bang=-
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.
I claim first use of "Error No. 0B" - or "No. 0B error." It'll be the new ID 10T!
"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.
The enemies of Democracy are
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!
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?
#fuckbeta #iamslashdot #dicemustdie
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.
You can never go home again... but I guess you can shop there.
...how something like a CVT would work for a wind turbine.
bork bork bork!
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.
Check out JoshJitsu.info for Brazilian Ji
According to the company's website, 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, which will create over 1,000 megawatts of new electricity in the next few years in British Columbia alone.
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.
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!
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.
MP3 Search Engine
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.
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.
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?
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...
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.
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.
The enemies of Democracy are
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.