Domestic Wind Turbines Blog

Archive for the ‘VERTICAL WIND TURBINES’ Category

I kinda like both positions actually i have no real preference

I’m looking for the maker or designer of a vertical barrel type wind turbine that uses a barrel type cylinder with helical slots from top to bottom. There was an initial problem with the barrel(stator) being too heavy for the base causing friction and drag. However this was overcome by putting magnetic rings (reversing the poles) between the Barrel base and the generator base, this kept the barrel and base apart by magnetic forces thus eliminating the friction and drag, this allowed the unit to work in extremely low wind speeds. Also with the helical slots, the unit would rotate no matter what direction the wind was coming from. I am looking for this information as i would like to use it for generating electricity from wind power to reduce my dependence on municipality supplied electricity which is increasing in price at an alarming rate due to gross negligence and miss management of the state owned power stations

Hey William, Five Toze is correct, there are great photos of these devices on Youtube and other sites you can find doing a proper google search, but they will never develope more power than your flashlight uses. The reason for this is simply their wind conversion efficiency. The best wind turbines in the world operate in the 25 to 30 % efficiency range, meaning they convert about 1/4 of the wind power they are exposed to into useable energy. The barrel types and other "Darrieus" Rotor designs run from 2 to 5 %. You’ll see them on online videos spinning radically in even light winds, but that is because there is no generator attached yet, or the generator is spinning with no load connected. As soon as you start extracting torque from the barrel to make energy, it will simply slow down and stop. Trust me on this, we have a wind and solar powered home, and I’m on my 3rd wind turbine right now, the other two didn’t work out either. There is a theoretical limit on wind turbine efficiency called the Betz Limit, I think it’s around 39%, look for that at Wikipedia, or the AWEA website below to understand it more.

I’ll list some good sources below if you want to learn more about wind power before you go into any construction phases. Take care William, and good luck, Rudydoo

im working on Vertical wind turbine and thinking to carry out a CFD analysis but need to know the force acting on the turbine rotor to carry out the analysis .. assuming the wind speed avarage is 4.5 m/s

A CFD analysis should be able to tell you exactly what the wind force is, so I do not understand why you need the force in order to carry out the analysis.
However, an approximate answer can be derived from:
force = rate of change of momentum.
Incoming momentum per second = (mass of column of air hitting rotor per s) x speed
= (density of air) x (area of rotor) x 4.5 x 4.5 newtons
Net outgoing momentum per second would be zero if the air came to a complete stop and just dissipated radially- otherwise you need to estimate what the air does after hitting the rotor.
The difference between those two figures is the force.

I am building a wind turbine and cant figure out how to calculate a torque of the wind turbine. For power I use Power =0.5 x Swept Area x Air Density x Velocity3
And the average wind speed is 11mph or around 5 m/s.
Air Density = 1.23 kg/m3

Hey Spy, your other answers here are on the right track, if it s tourque you are trying to acquire, you can take the watts you are expecting, or HP, and divide out the RPM to convert power output to torque. My guess is you don’t know what power to expect, and this is how you are trying to determine that. I have to ask a question: What are you using the turbine for? I’m hoping it isn’t for power production. Vertical axis turbines are handy for lots of interesting things, like pond pumps and wind chimes, but the reason you don’t see the power companies putting them up is because of their horribly low efficiency. Most turbines operate today in the 25 – 30 % range. There is a theoretical limit of around 39%, called the Betz Limit that no turbine can operate beyond, but the vertical units, such as a, "Darrieus," rotor, generally run in the 5 – 8 % range. But you don’t need to take my word for for it, check out the source and read the articles and formulas yourself. Your formula does not seem to have an efficiency variable in it, they do at the American Wind Energy Association website. There is a great article by Mick Sagrillo at their website about the vertical axis rotors worth reading before you build one, I will list sources below. Good luck with the project, and take care, Rudydoo

Hey ST, I’m surprised nobody has responded to this yet. Actually, there are lots of places that manufacture and sell horizontal wind turbines, but very few vertical. The reason is the vertical units are horribly inefficient. Despite what you may have heard or seen, or people have said about them, they are handy for little water pumps in the garden, or to run a few small LED lights, but even a large one will never run anything of significance.

If you are really in the market for a wind turbine, my best suggestion is first to get a subscription to Home Power Magazine. It is inexpensive, they run articles on lots of things to do with making your own energy, including wind turbines. About every third issue or so they will pick one item, like wind turbines, and compare all the different commercially available ones with all the ratings, power curves, prices and so on, so you can really compare them. Then most of the vendors run advertisements in the magazine as well. We started subscribing 12 years ago, today our home is completely powered by the wind and sun. If you subscribe, you will have access to the archived articles on their website, and you can look back at the issues that rate all the different wind turbines as soon as your subscription is started. There are some other places to get info, I will list some below. Good luck, and take care, Rudydoo

Anyone know instructions for how to make a MODEL of a vertical wind turbine that actually works?

http://www.google.com/images?q=vertical+wind+turbine

you need the turbine, and a brushed DC motor with permanent magnets for the stator.
if it’s going to turn at any significant speed, you need to balance it, or it’ll tear itself apart.

I want to build one of these?

http://www.instructables.com/image/FK8998JFXETSUMO/Building-a-Vertical-Axis-Wind-Turbine-VAWT-.jpg

I used stove pipe finding out it is a bit on the heavy side. Do you think aluminum gutters to a house will work better in the wind? It turns fairly well using stove pipes, but still seems to be on the heavy side. I been using bicycle rims. I’m trying to build a wind generator, thanks.

Yes aluminum is the lightist metal . . . thats why thy make planes from it

In my country, the climate is very humid and very warm all year long. I haven’t been able to find real solution to Green Homes for this kind of climate and in 5 years time, i’m thinking of building my own house.

Can anyone point out where i can find resources (information and physical material) for Green Home design specifically for tropical climate?

I do have some ideas, but still need some pointers on application:
1. Dessicant dehumidifier.
2. Passive ventilation (i’m thinking of utilizing differential pressure like burrows).
3. Solar Panel (equatorial countries benefit greatly from this)
4. Vertical wind turbine (where can i get it in Malaysia?)
etc…

ok.

The common wind mills, Horizontal axis wind turbines, or Vertical axis wind turbines? If there’s like a site that you know of that would say so that would help as well.

Coal, Gas, Hydro, and Nuclear are all cheaper than any wind turbines, and a lot more reliable. They produce 100% of the time. Wind turbines produce only about 30% of the time in a pretty good location.

I am doing a science fair project in which I am going to create a wind turbine and make electrical energy off it. I am planning to create a vertical axis turbine. I have two questions before i started tho…

1. Is there a way to create a horizontal axis wind turbine? (Is there website (like the one shown below) which shows a step by step process to build a horizontal turbine with cheap materail?)

2. Is there a way for me to store the energy created by the turbine? I dont expect to create alot of energy, but is there a way i can store the small amounts of energy created by the turbine? (like many in a rechargebale battery?)

http://www.re-energy.ca/ridethewind/buildamodel-2.shtml

thank you for your help

Try to hook your turbine to an existing product, such as a bicycle generator or a hand-crank charger. You may have to gear it down which will be complex. Or you could turn some kind of paddle wheel that pumps water "up hill" which might qualify for storing energy.