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http://www.wind-works.org/articles/Mag-WindPyramidalPower.html

Mag-Wind Pyramidal Power
July 13, 2007

by Paul Gipe


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As of July 12, 2007 no performance data--of any kind--has been provided by Mag-Wind or any other person.


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On February 2, 2007, a subscriber to the list serve awea-wind-home posted a message titled Mag Wind MW1100 Report. In the post the subscriber discusses an alleged FBI investigation of one alleged Mag-Wind dealer. Please see the posting for further details.


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Mag-Wind telephoned September 10, 2006 to say they will provide me with performance data when tests of their prototypes are complete. When, or if, they do, I'll report the results here. Mag-Wind's spokesman, J. Rowan, said that I under-reported the turbine's size and that it was bigger than I reported. Rowan said that the turbine is 6 feet (1.8 m) tall not the 4 feet tall listed on what claims to be a Mag-Wind brochure. This change increases swept area 50%. This reduces Mag-Wind's outlandish claims by a proportional amount. In other words, the claims are still outlandish, just less so. For example, specific yield drops from 8,900 kWh/m²/yr to 5,900 kWh/m²/yr.


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The pyramids have always been thought to contain some magical power. Maybe they do. Maybe Mag-Wind has found a way to tap into this magical power, because they certainly are not going to get much electrical power from this contraption.

They themselves say it's "much smaller than other wind turbines" that should be a tip off that they will follow this with outlandish claims. Mag-Wind doesn't disappoint. They deliver-on the wild claims. Some of the wildest I've yet to see.

They also add that it is "much more efficient than the old-fashioned windmill". Indeed it might be, but is it more efficient than a modern, highly efficient wind turbine? Doubtful.

Let's look at some of Mag-Wind's claims.

To begin, let's simply forget that it's conical shaped and assume that it's your garden variety vertical axis wind turbine. This is to Mag-Wind's advantage-and they need every advantage to meet their claims as explained.

Mag-Wind asserts, first off, that it can generate 13,200 kWh/yr in an average wind speed of 13 mph (5.8 m/s). Ok, that seems like an awful lot for a windmill that will be setting on your roof as shown in their ad.

Their windmill is 4 ft (1.22 m) high by 4 ft (1. ) in diameter at its widest point. The rotor sweeps a paltry 1.5 m².

Mag-Wind claims their turbine produces an average annual specific yield of 8,876 kWh/m²/yr! Yes, you read that right.

How does that compare with other wind turbines? Well, let's put it this way, the most productive wind turbine in the world--a real one--produces 1,500 kWh/m²/yr. Let's say that we find a super wind turbine at a super place, that is with a lot more wind than 5.8 m/s, and it generates 2,000 kWh/m²/yr then Mag-Wind is more than four times more productive than this imaginary wind turbine.

Ok, let's take another approach. Mag-Wind says its wind turbine will produce 5 kW at a rated speed of 28 mph (12.5 m/s). To produce that much power at that wind speed it would need to be 281% efficient! Yee ha. That's some windmill. Modern wind turbines, at best, can deliver 40% of the energy in the wind at any specific wind speed.

This turbine has a specific rotor loading of 3,360 W/m² of rotor area. Let's compare that to the over rated AirX. The AirX is somewhat smaller so we won't compare actual production, just rotor loading. Remember, the AirX doesn't even deliver what is promised. The specific rotor load for the AirX is about 400 W/m². The Mag-Wind claims to produce from its rotor almost ten times more power than the AirX which can't even meet its performance claims.

Ouch. I've never seen such outlandish claims before-and I've seen a lot of them.

Summary

This contraption doesn't even deserve the time I've spent to write this up.

Will it do what it claims? No. Not on this planet.

Would I buy one? No way!

Would I take one if it was given to me? No way.

What is it good for then? A roof vent or a lawn ornament. It could make a nice lawn ornament. It's not a windmill.

-End-


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