New more efficient wind power on the way

[His Divine Shadow]

http://opensourceenergy.org/txtlstvw.as ... 44417a564b

Terra Moya Aqua Inc. (TMA) is ready to go into production of a new vertical-axis wind turbine design that resolves some of the shortcomings that have plagued the traditional propeller design.

While many of the new design features are superior to the familiar propeller, Ron Taylor, who is the inventor of the new vertical design, as well as founder, Chief Operations Officer, and chairman of the board for Terra Moya Aqua Inc., is modest in his approach. He does not see his vertical turbine supplanting the existing propeller infrastructure, but rather views it as supplementing the field.

Ten years in the making, with seven iterations, and countless hours in a wind tunnel being tested by a premier wind engineering firm, as well as years of data collected from prototypes installed just outside of Cheyenne (one of the more windy locations in the U.S.), the TMA design is now ready for commercialization.

While the various propeller designs now in use harness from 20 to 28% of the wind’s power, with some newer designs edging to between 30% and 40%, Taylor says that TMA's design captures over 40% of the wind’s power, all across the profile, from low- to very high-speed winds. Depending on the harsh Wyoming weather, a production prototype is expected to be completed in 5-7 months, at which time they will then launch full-scale manufacturing.


Power from Push and Pull

Perhaps the most fascinating feature of this new design is the fact that it not only gathers energy from the push on the front side, but actually is pulled forward on the back side through a lift effect, similar to the principle that causes lift on a wing. "The back pressure creates a vortex that pulls it around, turning drag into lift," says Taylor.

The result is that the turbine spins just slightly faster than the wind speed -- 1/100ths faster on average, beginning with winds of about 5 miles per hour.

This facet is the "technology breakthrough" that makes it unique, according to Taylor.

This is the crux of their design, and of the approximate sixty claims between the two U.S. patents awarded and a third pending, and numerous international patents secured as well. "We have received notice of the acceptance of the 2nd USA Patent from our attorney but have yet to receive the printed version with the number," said Taylor. "Our patent attorney is very pleased with how broad our patent protection is."


Trial and Error

Earlier designs had 7-8 rotors on them, but in wind tunnel testing, they found that the wind tended actually to blow around the turbine – much as water flows a rock in a stream – rather than through it. This is a case, the inventor confirms, in which “less is more.” Their present design has only two rotor blades with three directional foils.

The independent Fort Collins wind-engineering company, Cermak Peterka, Perterson, Inc., that tested TMA's various design iterations, is considered one of the most competent in the world. For example, the company’s track record includes running the wind analysis on the WTC Twin Towers prior to their construction. TMA also used some of the same software used by large automobile and airline manufacturers such as G.M. or Boeing, for data collection on materials stress and wind flow.

As a result of implementing changes based on these professional analyses, TMA's latest vertical turbine performs eight times better than their first.


Ready to Come out of the Chute

Ronald J. Taylor
Inventor of the design, as well as founder, Chief Operations Officer, and chairman of the board for Terra Moya Aqua Inc.

Taylor said that his company has taken a very low-key approach in the development of their technology. "We would rather under-promise and over-deliver [than the other way around],” he said. Now they are ready for the spotlight, which has landed on them since a story that was released on Friday by the Casper Star Tribune was immediately picked up by the Associated Press. Their phone has been ringing non-stop.


Cost is Below Conventional Energy

Taylor says that the energy generation cost for their turbine comes in at around 2.5 to 3.5 cents per kilowatt hour, depending on the regimen, comparable to the most efficient propeller designs available. He arrives at this figure by taking into consideration the power curves, cost of construction, and all testing and design work. However, he might be overly modest in saying that. Just this year wind power reached the benchmark of becoming competitive with conventional energy generation, which is in the range of 4-6 cents/kw-h -- nearly twice as expensive as the number Taylor gave.

Taylor said that were it not for the production tax credits that wind turbines receive, there would not be nearly as many built, and they would not be as competitive with commercial generation systems. He doesn't think that the TMA turbine will require a tax credit in order to be competitive, especially in higher wind areas.


Handles High Wind Speeds

The optimal speed for harvesting wind energy, between 28 and 33 mph, is the same in both the traditional propeller design and the TMA design. However, TMA's vertical axis design can generate electricity from winds as high as 70 mph, while the propeller designs typically can only generate energy into the low 50's. This means that the TMA design can go into areas of stronger winds beyond the tolerances of the propeller designs.

In propeller turbines, the pitch of the blades must be changed depending on the wind speed. At lower speeds, the blades are more flat, and become more angled with higher winds, catching less of the wind’s capacity. Once the wind speed surpasses a propeller's top speed, it is designed to be braked to a stop. This eliminates damage from outward-thrusting centripetal forces which the props are not designed to handle.

The TMA vertical axis design, on the other hand, doesn't have to be braked to a stop. "We do not have to change the angle of our rotors," said Taylor. He said their fixed configuration works equally well at low and high speeds. Once the wind goes above 70 mph, the rotor is disengaged from the generator and gear box so as to not damage them, and is left spinning freely and harmlessly at close to the speed of the wind.

The TMA design is rated by structural engineers to handle winds of 156 mph without any damage to the structure. This is just below a category "F3" tornado wind speed. (Ref) Subjected to winds of 180 - 212 in early testing under controlled conditions, an earlier prototype withstood this force, with the only consequence being that a lock collar loosened by 1/8 of an inch.

In the 1960's, 108 mph winds wrecked an array of propeller turbines in Spain. TMA's prototype near Cheyenne was recently subjected to winds of 104 mph and "kept on going," said Taylor. "We do not take down he turbine in storm conditions as it is designed to handle nearly any situation. Obviously a hurricane or direct hit from a major tornado will do damage to anything man can build, but we are satisfied with the durability of the TMA turbine in most extreme wind conditions."

The ability of the TMA turbines to generate electricity during stronger winds offers a tremendous power advantage. The physics of wind power is such that for every doubling of wind speed, there is an eight-fold increase in the amount of wind power. Given the wind-speed limitations in presently-available horizontal-turbine technologies, the region of mid 50 mph to 70 mph will essentially be held exclusively by the TMA technology. This is double the 28-33 mph optimal range for prop turbines, and offers the promise of eight times the power output capacity in windier regions.


Kind to the Birds; More Quiet

One of the primary environmental drawbacks of the propeller wind turbines is that they kill birds. The tips of the blades spin much faster than the wind speed, chopping through the air sometimes at speeds of 200 mph. The birds generally just don't see them coming.

The TMA vertical axis design flows with the wind, at the speed of the wind. "It looks like a building to the bird," said Taylor. "We've never seen a dead bird at our test site." Likely this is because birds don’t normally fly into solid walls.

He notes that his company has been able to secure permission to install their turbine in several California counties where propeller turbines are banned because of the known bird carnage.

Also, because of their lower speed, the TMA turbines produce much less noise than the propeller counterpart.


Blends Better into the Environment

Another advantage of spinning at the speed of the wind, is that the damage to the TMA vertical axis rotors from particulates carried by moving air is negligible. A side benefit from this, which is very important to many people, is that the device can be painted to better blend in with its environment. Not being chipped by wind-driven sand or other small fragments of matter, the paint will last longer. Because it stands much shorter, about half the height of a comparable propeller design, the TMA’s visible impact on the landscape is much smaller as well.


Serviceability and EMF


An advantage of vertical-axis wind turbines in general is that the generator can be situated on the ground for ease of access and service. It is also can be protected better from the elements that can wear on the gears and generator.

Some other advantages of the TMA system, as listed on the company website are

* no field of magnetic resonance
* no interference with aircraft navigation or communication
* no ground resonance

In other words, there is "no electronic, magnetic or radar interference for aircraft navigation equipment."


Scalability

Finally, Taylor says the TMA design scales very well, performing "proportionately better." Still, he does not see a need to go to a huge size, but intends to design these turbines for output of between 1 kilowatt and 1 megawatt. A 1 kW turbine would stand around 18' feet high, including the control systems under the rotor area. This is in the low range to handle home power supplementation, and is small enough to be permitted in most residential zoned areas. The municipal-grade 1 MW turbine would be about 220 feet high, half the size of a comparable propeller system. The production prototype will be a 25 kW machine and stand approximately 34 feet tall.

Now that the hard work of research and development is over, and the process of production commenced, Taylor calls this project an "overnight success story. It only took us ten years to get there."

Assuming this is all as good as it's reported to be I still don't see it making a difference, powersupply will still be dependant on weather conditions.

[Ariphaos]

Wind is always blowing -somewhere- on Earth.

Or as some people up here tend to say

"Never been to the Dakotas, have you?"

[tumbletom]

Could this thing take hurricane level winds?

[Braedley]

Could this thing take hurricane level winds?

From what I read at slashdot, it's only limited by the strength of the support structure

[drachefly]

At those winds, it would disconnect the turbine from the generator to keep it from burning out and reduce stress on the frame... and hope not to be destroyed.