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Invelox wind turbine claims 600% advantage in energy output

Invelox wind turbine claims 60...
SheerWind's Invelox wind power generation unit is said to increase energy output by 600 percent
SheerWind's Invelox wind power generation unit is said to increase energy output by 600 percent
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SheerWind's Invelox wind power generation unit is said to increase energy output by 600 percent
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SheerWind's Invelox wind power generation unit is said to increase energy output by 600 percent
Invelox doesn’t rely on high wind speeds to produce energy
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Invelox doesn’t rely on high wind speeds to produce energy

SheerWind, a wind power company from Minnesota, USA, has announced the results of tests it has carried out with its new Invelox wind power generation technology. The company says that during tests its turbine could generate six times more energy than the amount produced by traditional turbines mounted on towers. Besides, the costs of producing wind energy with Invelox are lower, delivering electricity with prices that can compete with natural gas and hydropower.

Invelox takes a novel approach to wind power generation as it doesn’t rely on high wind speeds. Instead, it captures wind at any speed, even a breeze, from a portal located above ground. The wind captured is then funneled through a duct where it will pick up speed. The resulting kinetic energy will drive the generator on the ground level. By bringing the airflow from the top of the tower, it’s possible to generate more power with smaller turbine blades, SheerWind says.

As to the sixfold output claim, as with many new technologies promising a performance breakthrough, it needs to be viewed with caution. SheerWind makes the claim based on its own comparative tests, the precise methodology of which is not entirely clear.

"We used the same turbine-generator (with a given load bank) and mounted it on a tower as is the case for traditional wind mills," SheerWind told Gizmag. "We measured wind speed and power output. Then we placed the same turbine-generator system (subjected to the same load), again we measured free stream wind speed, wind speed inside the INVELOX, and power. Then we used the power-speed relationship over 5 to 15 days (depending on the test), and calculated energy in kWh. Six hundred percent more energy was for one of the days. [...] The improvements in energy production ranged from 81 percent to 660 percent, with an average of about 314 percent more energy."

All else being equal, it would seem to be the latter category that is the most useful indicator.

Besides power performance and the fact it can operate at wind speeds as low as 1 mph, SheerWind says Invelox costs less than US$750 per kilowatt to install. It is also claimed that operating costs are significantly reduced compared to traditional turbine technology. Due to its reduced size, the system is supposedly safer for birds and other wildlife, concerns that also informed the designers of the Ewicon bladeless turbine. Finally, the system also makes it possible for multiple towers to network, that is, to get power from the same generator.

Utility-scale availability of Invelox is slated for 2014.

Source: SheerWind

26 comments
Udhaya Kumar
Wow...but 600% is not from a reliable source
BigGoofyGuy
I think this is way better than the normal wind turbines; assuming it does what they say it does. I can see it being safer for birds since the traditional wind turbines have that problem of 'whacking' flying feathered creatures.
Mike Barnard
Okay, this tech gets hits on at least four of my questions that trigger red flags about bogus wind tech. Like many people who pay attention to wind energy, I'm getting tired of claims like this being taken even moderately credulously.
http://barnardonwind.wordpress.com/2013/05/08/invest-carefully-wind-energy-innovations-are-rarely-kosher/
Michael Crumpton
This screams bogus science. A standard commercial windmill is roughly 40% efficient (the theoretical maximum is around 60%). If this claims that it its 300% + more efficient than that it is 120% efficient, generating 20% more power than was in the wind. Magic! Or bad science.
Also this canard about generating power from lower windspeeds is also nonsense. The amount of power available in winds below 5mph is not worth harvesting. Wind power increases with the cube of the wind speed. In other words: doubling the wind speed gives eight times the wind power. So the power difference between 5 and 10 mph winds is 800%! It makes sense to optimize for higher windspeeds, because 1 hour of 10mph is worth 8 hours of 5mph and 64 hours at 2.5mph and 512 hours at 1.25mph.
Finally, a windmill can only extract energy from the wind that contacts it, so to get the same amount of power as a 20' diameter windmill rotor, you would need a "funnel" of equivalent size. It is hard to imagine the economics of making giant massive funnels is going to be better than a slender tower and a few slender blades.
Noel Frothingham
Michaelc, that which we can't see might hold the answers. We can't see the turbines themselves or where the venturi inlets go. Stacked turbines, each with its own supply of air compressed as it enters the inlets, might be able to achieve the stated efficiency,
Arahant
As others have said its likely bogus or bad data, but i'm holding out hope that its real or even if the data is abit off that its still an approvment. Even if its the same as others but cheaper it would still be good.
I think its a common reaction when something that comes along that seems to good to be true, that it normaly is.
But sometimes not.
To the person who said that for it to correct there would have to be 20% more energy than whats in the wind, doesn't account for how this device uses a funnel to bring wind from a much larger area and increases the wind speed, which as he states himself multiplies the energy collected. Not saying that makes the original article right, only that i think there is room for this to theoretically be possible.
We will have to watch this and see.
BluGrass76
It is a mistake to use the same sized turbine for the comparison. A proper comparison would match the effective inlet area of the duct at the top of the Invelox tower to a conventional wind turbine's inlet area.
It is also a mistake to use the exact same turbine blades. The concentrated wind speed is higher than the free stream wind speed and properly designed turbines will have an airfoil shape that has been designed optimally for the average wind speed. Since the average wind speed is different in a conventional turbine vs. a concentrating turbine like Invelox, you cannot use the same exact airfoil for comparison.
These mistakes would be acceptable at an eighth grade science fair, but where investor dollars are at stake it feels downright criminal.
b@man
That someone would try to trash this idea sight unseen makes you wonder about their true motives. Looks like a great idea to me, even if it's the same efficiency.
Joe Blake
As it says in the article these figures need to be treated with caution. But a couple of ideas occur to me. One of the reasons it may be difficult to generate power from low wind speeds is inertia of the entire system needs to be overcome, and losses to turbulence might be more than can be generated at low speeds. But from looking at the photos, it could be that with the funnel design will increase the wind VELOCITY while not necessarily increasing the total volume of air passing through the system. It could be similar to exchanging volts for amps in electricity, where the same amount of power can be utilised in different ways. 12 volts won't jump a gap in a spark plug, but if the voltage is multiplied many times, the same amount of POWER can be used to make a spark.
Secondly, since the blades of the actual rotor would be smaller than a traditional wind turbine of equal surface area of capture, the lack of mass would mean that again, inertia would consume less of the windpower. Thus it may be theoretically possible to generate more power from the same amount of wind.
Thirdly, whilst the mouth(s) of the funnels don't move, this would mean that on "back" side of the turbine head there may be a reduction in air pressure, a vortex, which theoretically could be used to generate power by using a second generator which runs in reverse. Crudely, it might use "suck" wind instead of "blow" wind.
Whilst I treat the 600%, or even 300% figures with caution, I'll say that this device may have more going for it than appears at first glance. I'll wait and see.
Nantha
I live in a "Low Wind" country. This method of funneling the wind so that low wind speed can also be used to drive generators means that there is much more generating time available. I like it.