Testing My Experimental Wind Turbine (VAWT)

[denisetakahashi]

you know what?i dont comment most videos but this one you made explains very well to even retards.i know calculation electronic and stuff but the way you show it is a sample for anyone who wants to put video on youtube!!very well mr.!!vey well

[Mrinfoone]

can you send me the dimensions diagram off the wings and or diagrams? so i could build one thanks

[sjh7132]

@Mrinfoone The wings are simple ellipses 9" x 1/2" x 24" and they are mounted 8" from the center at an angle of 0 degrees measured at the center of the wing.

[elwood173]

Thank you. One of the best turbine videos I have been able to find. Good info.

[215alessio]

the best output power is when the amps equal the voltage forming a perfect square in the voltafe amps graphic

respecting the max output amperage of your coils ofcourse

[sjh7132]

@215alessio That's true if the the turbine has the power to push the alt to that point. In my case the turbine was too weak so the peak power point would be more determined by the characteristics of the turbine and not the alt.

[walkertongdee]

I waw wondering if the wings are an airfoil shape like an airplane wing, I cant really see them and if so how did you choose the angle of attack? Would it be a good idea to be able to rotate the wings to set the attack angle? Please respond..

[sjh7132]

@walkertongdee

In this video the wing is just an ellipse (squashed circle) and it's mounted with a mount angle of 0 degrees. (aoa generally is relative to the wind, which changes depending on where the wing is in it's rotation.) In other videos I use air foils. Many people build their turbines so they can adjust the angle, I never have.

[craftmatic2]

I think you'd get far more power using Solar to drive a small steam engine and run the alternator that way...and for a similar price....

See the Green Power Science guy, Dan Rojas....

[sjh7132]

@craftmatic2

Or just a plain old solar panel. I have 1000 watts of those running already. I'm just exploring other options.

[purplemutantas]

@craftmatic2 Solar is good. But solar only works during the day. It's also not ideal in places where you get less sun. A combination of wind and solar would be better.

Where I live it's frequently cloudy. So I am looking into wind generators to go along with solar.

[ed4ed]

AT 00:41 LOOK at the Damn CHEMTRAILS in the Background! AHHHHHHHHHHHHHH!!!!!!!!!!!!!!!

[sjh7132]

@ed4ed

Those are high tension electric wires with the sun glinting off of them.  Sheesh, I don't live on a rocket test range or anything like that.

[2tostado]

@ed4ed Thank God someone noticed the rails in the back, that aint no natural phenomena . Keep ur head up

[wordpresswidget]

You might want to check out the discussion here fieldlines(dot)com-board-index­.php topic 138783.0 it has the calculations (for the most part) needed to figure theoretical power output on a VAWT, which is very different than the calculation for HAWT; the swept area is figured differently.

[sjh7132]

@wordpresswidget

The poster claiming the 2/3rds factor has made many assumptions. The fact that he made one or two VAWTs and used a little calc doesn't make him an expert. There are many other experts that disagree. In fact we've seen VAWTs that would be breaking Betz if you applied that 2/3rds factor to the area.

[wordpresswidget]

@sjh7132 first, I really like the work you're doing and even liked your video. I'm just a stickler for accuracy.

So, your math in the video is wrong (ronded?). applying the standard HAWT to your VAWT would yield P = 37.6W .5 * .25 * 1 * 300.763

and

>> In fact we've seen VAWTs that would be breaking Betz if you applied that 2/3rds factor to the area<<

That's impossible unless you're using a different formula too. P decreases the same amount as Area , to 25.06/2 in this case.

[sjh7132]

@wordpresswidget Yes I rounded. I think at the time i was estimating in my head and approximated 6.7 as 7.

Yes, breaking Betz is impossible, that's what I'm saying. If I take the measured power of some lenz2 turbines and use the formula for area that you pointed me to, it would sometimes break Betz. If i use the full area (d * h) Its about 40% efficient.

[wordpresswidget]

@sjh7132 I think you missed a piece of the example.

If you use 2/3 of diameter you are correct. The example

shows using 2/3 of the radius (4/3)/2 = 2/3. there is no

way using 2/3 of the radius would result in a P larger

than that found using the HAWT formula.

Did some quick calcs and found an efficiency of 34%

relative to Betz (.593 * 25.06 = 14.86) yields an output

of P = 5.05 using the 2/3 factor and your provided numbers.

This is in line with the experiment in the video.

[TheTwistedGypsy]

damn ! nice wind mill, but the hell is up with all the *Chem Trails* were you live. Thats scary.

[sjh7132]

@TheTwistedGypsy

i think you are mistaking the sun's reflection off of some high tension electric wires for chem trails.

[TheTwistedGypsy]

@sjh7132 ya know....I think your right...hahahaha

I have to slow down on my Alex Jones intake ... lol :-)

[ak471966]

you have explained more in one short video than all of the wind power people have "period". i am glad you have given a basic foundation for us newbys to understand and apply.

[sjh7132]

@ak471966

thanks, if you are really interested there is a good discussion group at the vawts dot net site.

[ak471966]

thank you

[ak471966]

thank you

[danie1murphy]

Thanks, someone who actually tests their turbine. So many youtube videos say "of course it's efficient, it just goes like crazy."

[sjh7132]

@danie1murphy

Thanks. Yes it seems that many people don't realize that power and speed are two different things.

[ldelossant]

 Hi, I am a High School Math teacher in New York City. Would it be possilbe to see a video of how you built the turbine's blades. I have several projects including building a wind turbine in class by dfferent groups of students ( one group will build the stator, the other he turbine and another will do the calculations ) Your viedo is very instructive. Would you please made a viedo on how to shape and build the blades? Thanks.

[sjh7132]

@ldelossant

Those blades I hot wire cut by putting current through a wire to heat it up and pulling it through the foam. Later I built a machine to do it. (It's shown in one of my later videos). You might want to consider doing a HAWT because you can just cut those blades from PVC pipe. (in my next video) Also you might want to check out the vawts dot net site.

[pangavamanos]

Very nice job. Informative glad you took the time to show us how you did this test.

Windthot

[R225O]

Thanks! i want to try to make one myself now :D very inspiring

[future2501]

You geeks are badass.

[pandksigns]

You are the ONLY person I ve found doing systematic experiments on your ideas and coming up with results that are meaningful and to a degree, accurate. I hope to see more of these backyard inventors following suit. I love your work. I'll post some of my work as soon as i get a camera. You've inspired me.

[HeavyDemir]

Umm the sweep area u talk of? Is it the hight * breadth of the blades, or the circle they scribe on the ground ?

[sjh7132]

@HeavyDemir

It's Height * Diameter

[kaloresi333]

Where did you find the money for all that equipment.If I had that i finished my project.good luck dude

[sjh7132]

@kaloresi333

That equipment pays my bills because it's for my day job. :-)

[Zypkin]

Your power problem is not in the turbine... it's in the generator!

You are trying to get 20W out of a generator which resistance is 46ohm and spinning at 25V.

Now, you dont specify which Tension and Impedance you measured (phase or line), however given that P=V^2/R if you short the generator (no load) you have 25*25/46 = 13.6W ...it's the best you can get: with no load... adding any load would just increase the overall impedance thus reducing the current and consequently the power.

[Zypkin]

@Zypkin ...a good generator should blow the coils if you short it... meaning its own impedance shall be so low to generate lot of current.

To get a low impedance you need to use less copper (less turns in your coils) but since you shall keep the voltage high you must definitely reduce the air-gap stator/rotor and improve the overall design of the generator :)))

[sjh7132]

@Zypkin

Or use more copper in terms of thicker wire.

[Zypkin]

@sjh7132 ...right... but this wouldnt work because would also increase the thickness of the coil which, being coreless, would lose most of the magnetic field :)

[sjh7132]

@Zypkin

I'll admit the alternator is poor, but it was enough to bring the turbine to a crawl. I was only using one phase to test which was 46 ohms. Had the alt been the real problem, the turbine would have continued at nearly full speed. I was hoping to have to use all 3 phases to load the turbine, but it was so weak it wasn't necessary.

[Zypkin]

@sjh7132 ...46ohm looks to me a huge number for a device supposed to make power (let's be clear, it's not Urs only... it's a common range for coreless axial flux machines I saw around). As a matter of fact commercial generators have internal impedance less than 1ohm... and that's because you have to get the power out of the machine and not waste it in heat :)

Anyway, I'm just tyring to help... I'm working on a ferromagnetic core axial machine, I hope I'll post my results within the summer.

[sjh7132]

@Zypkin

You are correct. That alt will never produce any serious power. It was my first try, and I didn't run through the equations before I made it. Still is has been good enough to test all my small turbines so far. (I haven't had one that could overpower it.)

[itsandbits1]

youtube.com/watch?v=EMtbMRp8ao­w  take a look at this blade model

[Shalek]

Hey I was thinking, I heard that a problem with vertical wind turbines is that, because wind hits both halves of the wind turbine it causes it to slow down. Couldn't one place a ramp to block half of the wind turbine and/or direct that half's wind to the other half?

Just some thoughts.

Thanks.

[sjh7132]

@Shalek

That's only a problem for pure drag type turbines, and in that case a ramp or series of ramps (so it handles all wind directions) helps. Most modern blades use lift and still drive forward on most of the upwind side. See my video about the lenz blade Simulation watch?v=Mk49ZgBTX5A

[Porterjebazillanator]

I hope you understand that the power equation is the power available in the wind, not the power you can produce. You need to add in Betz limit (16/27 or 0.5926) to find the max power you can actually achieve. So really, your turbine should be able to optimally produce around 25 watts. With efficiency factored in, 50% efficiency will lead to maybe 12 watts. Then there is inherent loss from the circuitry, so you are really looking at closer to 10 watts. Just so you know. Good video and nice idea.

[sjh7132]

Yes, I was a little naive when I made this first video. :-) Although when I calculate efficiency of my turbines, I use % of the power in the wind, not of the Betz limit. So the highest I could ever see is 59%. Its a little misleading to calculate based on the Betz limit, isn't it? A good turbine is 30% efficient so 12 watts could be reasonable.

[johnjejo]

@sjh7132

I sincerely thank you for making this video because you went further than most people and went behind the spinning flashing lights and tried to apply it. It also echoes my own steps so it's nice to connect with you.

[dankazi]

Excellent Video. Thanks for all the tips... Time to start making mine own VAWT....

[awizardalso]

Greetings, thanks for going a little deeper than most. There's more to it than 'it produces 'x' number of volts'! If I remember correctly, the perfect load would be equal to the resistance of the alt coils for maximum power transfer. Are you using a homemade alt? To get better efficiency, I believe you need to lower the alt coil resistance. In any case, I appreciate your efforts here. I live in the city and limited to VAWT's and I'm just starting to seriously consider alternative power.

[sjh7132]

You are correct, a lower resistance would help, also being closer to the magnets (My stator is warped.) The 'prefect load' also depends on what the turbine can actually produce. If you pull too much current, then the turbine just stalls. One of my other videos shows the Alt I was using.

[planetdarwin]

Nice work. Real science and engineering. When you calculated the wind area of your turbine, did you estimate the entire cross-section of the turbine (height * diameter), or just the one half of it the wind is acting on (height * radius)?

[sjh7132]

I used the full area (height * diameter) because this type of blade should create power all the way around. (except for directly into and with the wind)

[Alvaround]

Hey!

Thanks for the first half of your video

The last half should not accept that 20 Watts is too low. Because you have 20 watts an hour. If the night is windy you can have 250 watts accumulated whit only one turbine.

With 10 cheap turbines like yours, you can have 2500 watts accumulating by night. With that power you can heat a room for many hours. One hundred turbines for one home.

[sjh7132]

Thanks, but I was hoping for 20 watts and only got 5. :-( Actually 20 was unreasonable to expect. You are also confusing watts and watt - hours. It's true I could build up a hundred watt hours in a day. But a 1KW heater will use that in 6 minutes.

[TK42138]

Great video and one of the best explained wind turbine videos on You Tube. It's good to see real-world calculations being carried out.

[henriquesimonsen]

Very nice video. Thank you very much.

I am about to start my own prototype of VAWT and I wanted to know what kind of alternator you used? As for the wings, I also don´t know what kind of profile I should use.

But thank you already for the very good description video!

[sjh7132]

You might check out the Lenz2 blade. It's fairly simple and many people have good luck with it.

My alt is one steel plate with magnets and coils on the other side. It's not very efficient and next time I'll go with magnets on both sides of the coils, even though its more dangerous to make.

[Tubeglowfun]

Yay! A DIY vertical axis turbine actually producing power! 5 watts is better then the 0 watts that is produced every other video I have seen. Good job.

[777strongcoffee]

Thank you! Amazing - you were doing actual experimentation and showing your calculations and results and didn't just wait for an extraordinarily windy day to show us something spinning, but doing nothing. This is one of the most thorough and informative videos on wind turbines I've seen. Great work!

[flaskofcoffee]

Very informative - especially the explanations of how to calculate expected output, etc.

Thank you.

[allnewjacked]

If you need a place to test larger VAWT or a design that may not be neighborhood friendly enough, let me know. I have 5 acres on I-70 about 30 miles east of downtown Denver and another 35 acres 7 miles south.

[sjh7132]

Thanks for the offer.  I don't have anything big currently planned but I'll keep you in mind.

[FreeMagneticEnergy]

Thank you!

[WSBToulouse]

Love your approach. Your video is very complete. I am still with optimizing, scaleing up of the turbine. Thanks for sharing this.

[Saranase]

Correct. The tip speed ratio being greater than 1 proves that. However the efficiency was pretty good considering the errors in the surfaces of the wings which are quite visible at 0:20 on in. I do like the elliptical wings because of the relative ease of construction. I think I'll try out this design and add a few tricks I've been thinking of to see what I can get out of it. I have a few ideas what I'll make it out of.

[sjh7132]

Yes, well I cut those wings by hand tracing a crude template. Since then I've made myself a computer controlled foam cutter. My next experiment is going to use NACA0025 foils.

[sjh7132]

Also since I did this turbine, I've done lots of computer simulations and calculations on this design. It turns out that it's very easy to stall it with a resistive load, and my measurement system may have been too crude to actually find the peak powerpoint. (The peak power point and the point where it stalls to very little power are very close.)

[Saranase]

Some things to consider. First your video is one of the most thorough that I've seen. You document your work well.

I was wondering how you derived your measurements (8", 9", 1/2", 2'). Also where did the idea for elliptical wing cross sections come from?

Your efficiency measurement I think needs adjustment. Only 1/2 of the VAWT counts for swept area, so the .25m becomes .125m. Power goes from 40 to 20watts @100%. 25% of 20 is 5 watts. And what did your turbine produce? 5 watts.

[sjh7132]

Thanks, I basically picked my initial designed based on what materials I had handy. I had read that an elliptical wing was a good place to start.

Actually the whole VAWT counts for swept area. The lift type blade is supposed to generate force all the way around. Drag types only do it on the downwind side.

[qqashtr]

Thanks for adding science to your experiments. Could you discribe your alternator in more detail? Do you have any steel in it to concentrate the flux? Is there any noticable cogging?

[sjh7132]

I go into more detail on that alternator in one of the other videos. Basically the magnets are on a steel plate and the coils are just backed by wood. Because of the warp in the stator it's not very efficient. Magnets on both sides is probably a better way to do it, but more complex and more dangerous. There is no cogging in this alt.

[qqashtr]

Thanks for your reply. I could not find the video. Could you give me more details like number of magnets and number of coils and number of turns per coil?

Does this blade (elliptical) design perform better than the Lentz of same size? Are there any starting problems?

[OceanportECP]

This is one of the best DIY videos on You Tube. Most videos lack a voiceover to explain what is going on and usually fail to show all the componentsof a complete system. Thanks for sharing your experience with a clearly well made video.

[GreenEngineer07]

Great Vid man. One additional comment though is you need to measure the inductance of the alternator. then you can calculate the power factor and find out how much of that power is real and how much is imaginary. Send me a message if you have more questions about this. Also I would like to invite you to contribute to a collaborative website, see my channel for details.

[gggatttorrr]

Excellent Video!!!! Great data. Way to approach from the math side and real world testing. Keep it up.

[DeanC993]

very nice setup! likr the anemometer, are u going to make any electricty out of it?

[sjh7132]

Eventually I will generate some power, but this is just a small test turbine to experiment with wing shapes. (The wings can be replaced by removing a few bolts.) Once I get it right, I might make a bigger one.

[sjh7132]

Dorry Dean, meant to reply and accidentally removed your last comment. Youtube gives no second chances! Anyway, voltage is all in the speed of the turbine, size of the magnets, and the number of turns in the coils. I'm using pretty big magnets, and about 175 turns * 3 coils per phase.

[DeanC993]

i have a motor so im not going to bust up and count coils but its 7 volts at 15 mph, i live in Nashville tennessee and we dont get much wind but its an experamentel model for me if you go to my profile you will see a picture of the motor with the blades on, thanks and are u going to make another video about your wind turbine? thanks

[Caleb6543]

Excellent video! Finally, a little engineering! I think you were optimistic with your expected power output. The Betz limit is 59%; meaning you could only hope for 59% of the available power. A Gyromill configuration operating at a low tip speed ratio will only have about 25% of maximum power. So if you get 10 watts, you'd be doing well!

[emagnets]

Safety First, i have used ring magnets on one of mine to act like top baerings and it works, but my turbine wiegh 45lbs.

anyway, good job, but now that you started you cant stop, look at me, so far i built 14 diffrent turbines and still have 3 unique ideas that i need to biuld.

keep up the good work.

[emagnets]

not bad vid...alot of info...you have a great view. good work.

dont you think Mass has anything to do with it??

[sjh7132]

Mass would help keep the speed (and power) more steady in a gusty wind, but on average it shouldn't make any difference. (Assuming it's not so heavy that the bearings are stressed.)

I made this light so that if it flew apart, it wouldn't kill anyone or damage my house.