Design creates pull on the back side, contributing to 40%+ wind
conversion efficiencies; doesn't kill birds; runs more quietly; and
doesn't need to be installed as high, blending better with landscape.
Generating costs estimated at 3.5 cents per kilowatt-hour, surpassing
conventional energy sources.

by Sterling D. Allan
Open Source Energy News - Exclusive Interview

http://opensourceenergy.org/txtlstvw...d-2a44417a564b

CHEYENNE, WYOMING, USA -- 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.

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.

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" .

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 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.

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. TMA's latest vertical turbine performs eight times better than
their first.


The energy generation cost is 3 cents /k h, 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.

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 doesn't think that the TMA turbine will require a tax credit in
order to be competitive, especially in higher wind areas.

The optimal speed for harvesting wind energy is between 28 and 33 mph.

It 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.

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 centrifugal forces which
the props are not designed to handle. The diameter of the rotating
vertical axis turbine is much less than of the propeller design.

The TMA vertical axis design, on the other hand, doesn't have to be
braked to a stop. 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.

Taylor said the TMA turbine will begin to spin with winds of around 5
mph, at which point it is just free-wheeling. It begins powering a
trickle charge as the gearing system engages when the wind speeds reach
between 8 and 10 mph.

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.

Effing Google splodging the damn posts all over the damned place!