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Old July 17th 08, 02:36 AM posted to rec.aviation.homebuilt
clare at snyder dot ontario dot canada
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Posts: 56
Default Generators that use Wind power.

On Wed, 16 Jul 2008 07:01:50 -0700, Joe Brophy
wrote:

On Sun, 13 Jul 2008 00:44:12 -0700, "a" wrote:

I will be reading the comments in this newsgroup for the next few days and
learning from those that are positive and helpful.

I know that this is an out of topic posting to this newsgroup. That is a
reason that I am posting here. I want to learn from people that are not in
the business of cogenerating energy. I want to read in this newsgroup
valuable comments from a fresh perspective. By off topic posting to random
newsgroups, herein I may gain an honest response.

There are definition links for you to read. There is physics data, and NASA
data that is referenced. I would like your honest opinion. I would like to
read logical responses. Childish screaming about commercial posting or out
of topic posting to this newsgroup will not slow my quest to find logical
and valuable responses. Someone on this newsgroup will be able to think for
themselves and will give me an honest and logical response that I may learn
from and potentially use. I look forward to your opinion.

www.reasonablepower.com

Topic: WIND POWERED GENERATORS.

I would like to introduce you to a new wind powered generator company.

These are specifically for LOW wind speeds. These are affordable sized for
the average (non-city) U.S. homeowner.

This is a very small company. These are being built one at a time.

The page is at ReasonablePower.com

http://www.reasonablepower.com

Please take the time to look at the page.

If you have a valuable response whereby I may learn and do better as I build
this company, please post your response to this newsgroup. I will be reading
postings herein for a while.

Thank you.


Got a picture of your blades?



OK, I'll bite.
To a point you are right. HOWEVER.
An airfoil can turn faster than the wind passing it. This is due to
the lift. Three blade turbines are designed to turn slowly. They are
designed to do this so the tip speeds do not get too high. Due to
their size, tip speed is a definite factor. They make them BIG because
they are , as you stated, levers. The forces exerted at the end of a
long blade impart a LOT more torque than the forces neer the root. The
taperes blades distribute the torque load across the whole blade.
Blades with big paddles at the end put excessive loads on the blades,
as well as more drag. The blades need to have a twist in them so the
angle of attack of the blade is relatively even across the blade (they
have the same "bite" for the length of the blade)

The old farm windmill (most good ones) ALSO used an airfoil. Granted,
it was a single sided foil - convex on one side and concave on the
other. This also enabled the turbine to spin faster than the wind. The
"aermotor" designs were high speed low torque devices, and had a
gearbox on the turbine that reduced the speed and increased the torque
to operate the water pumps.They were, IIRC, about a 16:1 ratio (two
stages, 4:1 each). Most could also be "shifted" from long stroke to
short stroke. SHort stroke could pump water with less wind, but pumped
slower - and could also pump higher.(more mechanical advantage).

These devices have historically not worked well for generators.
There are reasons the large diameter 3 pladers are used extensively



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