I have very little knowledge about this subject but was wondering if e-bike rear hub motors would work? ever hear of anyone using one? I modified one to be oil cooled and could run 3500watts through it continuous to power a bike.
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I just picked up a treadmill motor as they are dc permanent magnet motors with encoders for another project.
I wanted to throw it out there as an idea namely because the motor isn’t attached to the bearing, kind of like a drum brake. The also output AC current which is more efficient like an alternator and you are able to run AC longer distances without as thick of a cable because of the resistance differences. (Pulsed dc current is similar which is used in high voltage dc power lines.) however it is 3-phase output so you need extra wires.
This site actually goes through the rewiring, rectifying and such of the motors.
http://www.yourgreendream.com/diy_fisher_paykel.php
In the end, Obtanium always wins. 
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Chris K. in Luxembourg did this video in 2012.
also check out his recumbent bike videos. A bit on the wild side, but good clean fun! 
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Obtanium is great for saving $$. Practicalium is another option for ensuring you get useful power. It utilizes a wealth of published data that is available. Practicalium has good characteristics that have been tested with predictable results. It is more resistant to those unstable isotopeslike “nevergotitdunium” or “Whatheheckisthatium”
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Interesting topic. I would like to submit this information for consideration.
I like the idea of wind power, but the information provided by this outfit that deals in wind power generation is hard to dispute. I would still give it a go, but it seems to be a marginal power source. It could fit a power generation scheme as a supplement (wind may blow at night, or when it’s cloudy), but for most applications it isn’t going to perform very well. Also, blade geometry, high wind furling and overspeed protection, maintenance access, and lightning protection make for complications.
If there’s access to any amount of flowing water, the same generator will provide far more. I could get by well on 100w constant power, versus an occasional 1000w peak.
Solar electric, and direct solar thermal are probably the most practical for most situations.
Ceiling fan motors converted to generators are the other practical approach, (though I want to get my hands on some of the Paykel type motors), and will have the same advantage of ac transmission. I don’t think there’s a cheaper, or more available generator for low rpm power.
Regards,
Garry Tait, Manitoba
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A savonius style Vawt out of a 55 gallon drum works at lower wind speeds closer to the ground and handle changing wind directions easily. They aren’t as efficient but work more often. I haven’t figured out what you need to use for bearings, but Obtanium for the rest of it is pretty straight forward.
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Car wheel bearings seem ideal to me since they are good for side thrust and axial loads. I agree that for many of us the old savonius rotor is good. It is not as effiecient, but the payback time is minimal. you can just add a few more of them if you need more power.
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I used to think that vertical turbines would have the advantage, the same as your logic. But, there’s an inherent loss of efficiency, because the blades / buckets have to come back against the wind. The wind coming from different directions also had me sold for a while, but as that link describes, wildly varying wind just indicates turbulence, and you will never get efficient power from turbulent air. The article also makes a strong case that start up wind speed isn’t really significant, as the power at low speeds is negligible, average wind speed in clear air is the key for power.
The main attraction I can see with a VAWT would be that it could drive a vertical shaft down to ground level, making for fewer maintenance headaches, and less weight on top of a tower. The tower, erection, and periodic lowering for bearing maintenance will still be headaches. Grease lines with grease nipples at the base would be handy. A VAWT on top of a tower would also need some kind of centrifugal brake for safety, as there’s no simple way to furl it in over speed winds.
It would still be nice to see one spinning.
I agree with Andrew about the stub axle / salvaged axle.
Regards,
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Right they are max around 10% efficient vs like 30+% for a 3 prop turbines as you run into a similar problem with interference with more props. The key differences are the windspeed only needs to be 4-5mph before the savonius starts producing vs like 10-15mph winds for the turbine.
The need for a 100w continuous current as being useful (ghost loads, lights?) along with the low cost and ease of construction is why I mentioned it. It is just going to produce power more often but less of it which is a closer simulation of continuous power.
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I have thought about building a wind turbine but where I live there is not enough reliable wind. So I have considered inhancing air movement by building a large chimney to get the up draft efect.
In the big old smoke stacks there always seemed to have a large volume of air rushing in and up. If it Is sunny the air could be heated at the base to inhance air flow also if a the top was designed to utilize wind flow to create more air movement in the chimney. I am thinking a turbine or squirrel cage installed in the base for easy servicing. Am thinking water tanks welded together to get a good size for volume and maybe 50 -60ft to get a good lift. Any thoughts.
A friend who has done work on powerplants tells me that there have been workmen sucked half way up those huge chimneys by the draft.
I also remember an article in an old popular science about using a chimney effect to spin a turbine.
I’ve thought of trying just what you suggest, but hasn’t happend yet. I’m not sure how big of a chimney would be required to get a useful amount of power.
I had thought too, of adding a venturi to speed up the air as it passes the impeller.
If you try it, be sure to let us know the results, good or bad.
Something like this?
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Yes I will. I have moved to eastern Wa and now getting settled in. So I am going to startcolecting materials for it and many other projects I want to do. I am thinking about building a vortex impeller so it won’t need the high speed.
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Several YouTube’s on “Tower Electric Generators”. All a little different. One said it was to be built on the Mexican boarder of Arizona and be completed in 2015. Later I will have to see what I can find on it and if it ever happened.
Barstow Calif has a tower with a field of individual reflectors, all continuously moving the direct the sun raze to the top of the tower. At the top is a structure full of water that turns to steam and the steam is piped to turbines on the ground.
With all of these bright ideas, why isn’t anything really taking off? I have thought about getting electricity from the tide in the ocean. Obama has been pushing this stuff for 8 years and yes we have some wind turbines but not near enough to replace our coal and atomic plants. TomC
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If I had to guess it’s part storage problem and part fear of stranded assets. If you have a power plant that is at half life you will do anything in your power to see it to end of life to realise it’s full profit potential. The change is coming and accelerating. Distributed power systems, feed in systems, better insulation better appliances it’s going to come… when though, who knows.
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Chris I’ll be up your way picking up a M 1080 a 6 Wheel Drive military truck on Friday. And yes I am thinking about how I can put a gasifier on it
at 7 miles to the gallon , you have to I will need an entire forest to drive this thing Brit lol
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A company in northern Colorado builds large wind turbines. Each blade is an over size load on a truck. When going south on I 25 they stop over night near me. Sense I would like to build a much smaller one and am just curious I stopped to see how theres were shaped. Two things suprised me. One was how thick the blades were. The ratio of thickness to with was about 1 in 3 or 2’ thick to 6’ wide. The other was the inner end, near the hub was cupped on the flat side near the trailing edge, like flaps on a aircraft wing. Since the center moves much slower that should give the blades more tork. Hope this helps if some one trys to build one. Will I hope know more next summer when I can cement in my tower and get one up. It will have to be tall because I don’t want to cut all my trees.
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I think that the solar tower idea forgot something when the computer modeling looked like a cinch.
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