Small Windmills
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Dean,
Hey from Santa Cruz. Been reading all the information here for a few weeks now... 2 words, THANK YOU. Great find here, you guys and gals to an awesome job here.
Now, onto your question. While I have not seen the show you speak of there is another wind turbine I have been following since seeing it back in 2005 on Beyond Tomorrow. I would seriously take a look at the Turby. There is a small translator on the top left for english. AMAZING unit to say the least.
If you do find the ground based one, I would love to read more about it. Hope this helps.
Regards,
Mike
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I posted up an article on Wind Power where I not only listed Vertical Axis wind generators, but actually showed some pictures of them.
Vertical axis are MUCH less efficient than horizontal axis machines, but the make sense for places that don't allow tall towers.
Most places won't allow or insurance companies won't insure your property unless you have at LEAST 150% the height of the tower to your property line.
That's VERY impractical for city applications.
If I remember the show correctly (been a couple of months since I saw it) Hagman had super strong wind resources, So an inefficient turbine design wasn't an issue for him.
You wouldn't believe how stupid the building restrictions are for stuff like towers in some real estate markets!
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I noticed from Pacwind's website that tower heights of most of their generators were shorter than most conventional wind generator tower. Does a VAWT not need as tall of a tower? That would be a big plus if they can produce more usable power from shorter towers in turbulent wind. I know any generator would be more efficient higher up, but you have to look at the return on your investment. The tower is usually the biggest cost of a wind turbine. I like the low maintenance aspect of Pacwind if it's not all sales hype.
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Horizontal windmill is like the giant ones you see off shore all the time, and they are up to about 2 megawatts right now...
But getting bigger every day...
Vertical windmills are only sustainable in high wind areas, since verticals take more wind to produce any current.
(that's why you don't see them very much)
The problem there is I don't have 2 million to get one like that!
I have to stick with little generators that are mostly just rewound car alternators!
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Vertical axis are normally used on buildings and such where you CAN'T have a tall tower, that's why they are vertical instead of horizontal axis on a tall tower...
Vertical axis on short towers never get up into the 'Clean' airflow, so they are less efficient for that,
AND,
The vertical design it's self is less efficient, so they don't put out as much for the wind they do get.
It's not a perfect solution, but it's chipping away at the problem of fossil fuel usage when you can, and were you can!
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Bladed types need to be away from stuff like trees , buildings , and from the slopes of hills ,otherwise they wont work to their optimum efficiency.
This is essentially because of negative turbulence that structures or land masses like these interupt the gusts to some degree.
VAWTS seem impervious to this because they essentially take the gust from whatever direction and if the blades are helical , draw the gust(no matter which direction it comes from) , upwards giving the blade a certain amount of lift also.(bit like them chimmneys that have screw - thread like veins on the outside of them - they keep them upright in high winds ! )
IMHO if your on a stealth bug out area , VAWTS will give you a less of a profile above the land, bladed ones need to be an apreciably lot higher in the air thus more susceptible to detection.
Cheers , Thomas ,North Wales , UK
This is essentially because of negative turbulence that structures or land masses like these interupt the gusts to some degree.
VAWTS seem impervious to this because they essentially take the gust from whatever direction and if the blades are helical , draw the gust(no matter which direction it comes from) , upwards giving the blade a certain amount of lift also.(bit like them chimmneys that have screw - thread like veins on the outside of them - they keep them upright in high winds ! )
IMHO if your on a stealth bug out area , VAWTS will give you a less of a profile above the land, bladed ones need to be an apreciably lot higher in the air thus more susceptible to detection.
Cheers , Thomas ,North Wales , UK
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'NEGATIVE TURBULENCE'?Bladed types need to be away from stuff like trees , buildings , and from the slopes of hills ,otherwise they wont work to their optimum efficiency.
This is essentially because of negative turbulence that structures or land masses like these interupt the gusts to some degree.
Isn't that like saying, "Ain't Not Got No More"?
ANY disruption (Turbulence) in the air flow is 'Negative' to production!
SO, just say 'Turbulence'!
Blowing on the NON PRODUCING blades makes for resistance and drag that limit the output power of the Vertical Axis mills...VAWTS seem impervious to this because they essentially take the gust from whatever direction and if the blades are helical , draw the gust(no matter which direction it comes from) , upwards giving the blade a certain amount of lift also.(bit like them chimmneys that have screw - thread like veins on the outside of them - they keep them upright in high winds ! )
That and they really don't lend themselves well to being on tall towers that can get up into clean air flows...
With Horizontal Axis mills with blades, all the fan surface is producing torque to turn the generator,
AND,
The design lends it's self well to being on TALL TOWERS where the air flow is much cleaner and has less 'Turbulence'...
Not necessarily true...IMHO if your on a stealth bug out area , VAWTS will give you a less of a profile above the land, bladed ones need to be an apreciably lot higher in the air thus more susceptible to detection.
The bladed windmill can be on a low mount, like a roof top, but it's MUCH less efficient than it would be on a taller tower, that's why you put them on tall towers!
Verticals are used on buildings because in most places, you MUST have 150% the heights of your mill to the property line...
So if the mill goes over, it won't get into the neighbors yards!
Jay Leno and the like use Verticals in the city for this reason... A tall tower would require buying stupid expensive LA land from the tower, to 1.5 Times the distance to the top of the rig in a radius out from that point!
The Verticals are not 'Towers' and not subject to the laws (Yet) and as long as they land on their own buildings, they are legal (for now).
They didn't use verticals because they are more efficient!
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Don't get me wrong, I think Verticals, Horizontal Drum, bladed towers, are ALL GOOD!
ANY Renewable Power you make is GOOD beyond belief!
And ANY GOOD you can do is much appreciated!
Just don't get roped into the advertising hype and believe that the verticals are more efficient than the bladed types!
If vertical 'Drum' types were more efficient, they would be in the huge fields of wind farms, not bladed types!
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"You say Tomayto ,I say Tomato..." LOL
Its a question of semantics right??:
The wind arriving in the front of the turbine blades must be stronger than the turbulence behind the blades, ( Turbulence equates to less speed , there fore less potential energy converted) this turbulence can be derived from nearby buildings . trees , landmasses , or anything that act as a braking effect on the backside of the blades - whichever position they have turned to. This is known as The Wake Effect.
Because of this effect , high level turbines are more often than not , placed between 3 and 5 times the tip to tip length AWAY from each other for this very reason.How many buildings do you see among the giant wind farms now found on most plains and coastal areas, you very rarely seen to have wind farms in amongst built up areas.
Disregarding local planning law ,(Im in UK ) The physics still hold true -universally.
If it is the case that you were merely correcting my questionable double negative then I concur, negative turbulence is a tad confusing but was merely typed to indicate that any turbulence is bad to the newcomer to this technology.
The "stealth" option of Vawts was merely a way of elucidating on the smaller more compact and less visually intrusive signature that a pole and a turbine has.Nothing more....
Next time Ill pack my Thesaurus and Nomex suit I add my 2c to a thread
Nice one Jeeps
Thomas , North Wales , UK........and surrounded by wind turbines !
Its a question of semantics right??:
The wind arriving in the front of the turbine blades must be stronger than the turbulence behind the blades, ( Turbulence equates to less speed , there fore less potential energy converted) this turbulence can be derived from nearby buildings . trees , landmasses , or anything that act as a braking effect on the backside of the blades - whichever position they have turned to. This is known as The Wake Effect.
Because of this effect , high level turbines are more often than not , placed between 3 and 5 times the tip to tip length AWAY from each other for this very reason.How many buildings do you see among the giant wind farms now found on most plains and coastal areas, you very rarely seen to have wind farms in amongst built up areas.
Disregarding local planning law ,(Im in UK ) The physics still hold true -universally.
If it is the case that you were merely correcting my questionable double negative then I concur, negative turbulence is a tad confusing but was merely typed to indicate that any turbulence is bad to the newcomer to this technology.
The "stealth" option of Vawts was merely a way of elucidating on the smaller more compact and less visually intrusive signature that a pole and a turbine has.Nothing more....
Next time Ill pack my Thesaurus and Nomex suit I add my 2c to a thread
Nice one Jeeps
Thomas , North Wales , UK........and surrounded by wind turbines !
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have any of you checked out the M.A.R.S. wind generators? they seem to be very inexpensive for the amount of power they potentially can produce, but you pretty much have to be in the middle of nowhere with tons of land (it seems to me) to have one...
Magenn Power Inc.
Magenn Power Inc.
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vawt
The wind doesn't blow in straight lines...especially withing 100 foot of the ground. Topography as well as trees, structures and other influences cause the wind to roll like an under tow current when that close to the ground. It causes up wind horizontal turbines to whip back and forth trying to stay pointed into the wind. Vertical axis machines don't need to turn up wind in order to take advantage of wind energy, but they are less efficient. Watch a flag someday and see how it lifts, turns, drops and changes direction constantly and you'll see why horizontal machines take such a beating. They are, however the most efficient units out there and less costly and difficult to build. I know a lot of "home brew" wind energy folks would argue, but to generate comparable levels of electricity the vertical axis machines need to be huge and well built. Balancing is the key issue or they'll vibrate themselves apart.
The wind doesn't blow in straight lines...especially withing 100 foot of the ground. Topography as well as trees, structures and other influences cause the wind to roll like an under tow current when that close to the ground. It causes up wind horizontal turbines to whip back and forth trying to stay pointed into the wind. Vertical axis machines don't need to turn up wind in order to take advantage of wind energy, but they are less efficient. Watch a flag someday and see how it lifts, turns, drops and changes direction constantly and you'll see why horizontal machines take such a beating. They are, however the most efficient units out there and less costly and difficult to build. I know a lot of "home brew" wind energy folks would argue, but to generate comparable levels of electricity the vertical axis machines need to be huge and well built. Balancing is the key issue or they'll vibrate themselves apart.
Wind power
Pacwind - home I didn,t see what Larry Hagman has for a wind turbine but Jay Leno has a Pac Mill on his studio. Here is the web site. Phil
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