DIY PM generator - Small Hydro system

[folens]

First of all, thanks for everyone who is posting his or her projects, it was very useful.

I'm planning to build a hydro system for our boy-scout camp in july here in Belgium. My goal is to build a system that can provide sufficient energy to load about 10 cell-phones Batteries for the gps, torches, radio, ... This mean something between 10 and 50W. 10 would be nice, 50 would be great...

I have a few concepts in mind, first of al a simple waterwheel with some bike-dynamo's on, depending on the power, I can switch on 1 up to 4 dynamo's, generating at their best 3 up to 12 W at their best.

The second idea is a waterwheel connected to a direct drive engine from a washing machine. The problem is finding such a motor.
Because finding a direct drive engine might be difficult, i have the idea to build an alternator myself.

I have access to a lasercutter where i can precisely cut plastic to make a rotor with neodymium magnets on and the stator for the coils. I found different construction, radial and axial, my preference goes to an axial generator because of the easier construction.
 
While searching online I calculated that 100RPM would be enough if I have 32 magnet poles. In the pics below you can see some of my first ideas, but i miss the basics. I don't know how to orient the magnets, the size of the coils, the height, the area of the coils. The space between the different magnets...

I there anybody who can help my find manuals of inform me with your own expertise? Any help would be great, keep in mind i have a small budget, the water wheel would only work 1 month a year so big investments are difficult.

https://www.dropbox.com/sh/n0iqhym0wqqw6nq/T4f61sVNxJ/01.jpg
magnet orientation 1
https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:02.jpg
magnet orientation 2
https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:04.jpg
magnets close to each other
https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:03.jpg
larger distance between the magnets.

https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:05.jpg
This is the creek i would put the waterwheel in, because of the distance i have no more information about flow and drop...


Thank you in advance for any help, advice, ...

J. Folens
Belgium

[hydrosun]

I can comment on the bike dynamo idea. My first hydro used a wood water wheel attached to a bike wheel and a dynamo running on the tire. It worked but I had to be carefull with the tension to keep from slowing it down too much. Because I was using the water from a one inch pipe at 15 psi I was able to change the setup to tiny buckets wrapped around the shaft of the dynamo itself. It lasted through the winter, but the bushing was very worn and wouldn't have made it through another season. These bike dynamos had only a oiled bushibg onstead of bearings because the hours of use on a bike is so low. On a hydro you would have to replace twice a year. My next try was with a low speed dc motor. It's week point was the brushes and commutator wearing out on two years. A hydro running 24 hours a day wears out anything dragging. I'm now using ceramic bearings to try to increase time between repairs in a damp long running situation.
Chris

[gww]

I don't know how much dynomos cost but the washing machine motors might be had for about $100 at a website called "randys workshop" and the voltage convertion info can be found at "the backshed" 
Hope this helps
gww

[ghurd]

Something I learned about small power output and motor conversions?
It is much more efficient to start with a big motor.  And that means it is a lot easier to get a few watts out of it.

Small motors have long tiny wires in the coils, and local motors for you will be worse because of the 220VAC grid (vs my 110VAC).
The high resistance coils waste MOST of the power before it gets out of the PMA.

It should be fairly easy to start with a 750W (1HP) 220V 3-phase 1000RPM at 50Hz (1200RPM at 60Hz) 6-pole motor.
Find the star point, cut, add 3 extensions to the 3 'new' wires.  Or find the 6 input wires.  Add 3 bridge rectifiers.
Then add 6 clusters of neos to the rotor.
G-

[electrondady1]

if it's for boy scouts, why don't you build some thing up out of magnets and bicycle parts some thing they could duplicate at home.

[hiker]

put those boys to work and just make a simple pedgen from a used treadmill motor and a old exersize bike..
my grandsons have a blast lighting up a 50 watt headlite--the oldest is in 2 grade youngest is in preschool...
seems to me you would have a endless amount of power..boy scouts !!
 just hook up a used auto flat  belt belt to the flywheel  down to the motor--and crank away..hook up a diode as well to the motor output so it wont be powered by the batt, your charging.....everything could be mounted on a piece of plywood--motor bolted down then put the bike on top of the plywood and slide it back for tension--body weight keeps it in place...... happy cranking...............................hiker.
ps...this would put out more than 50 watts--depending on the motor and strength of the person maybe 200 watts plus..........i hit 10  to 15 amps with my motorhome emergency start up pedgen...have funnnnnnnnnnnnn.

[folens]

thanks for the comments & info

https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:untitled.16.jpg
https://www.dropbox.com/sh/n0iqhym0wqqw6nq/-wqmLmLu5w#f:untitled.14.jpg

I draw the turbine & alternator as I see it right now. A plastic rotor & stator with 32 permanent Magnets (http://www.supermagnete.be/eng/Q-30-10-05-N) and 32 coils

on the same axis of the rotor i put a 340mm(13,4inch) turbine, 300mm(12inch) width

i know plastic isn't the ideal material for the rotor and stator due to its poor magnetic permeability but it is easy for me to laser-cut it.

i hope you can see the images, the idea is to hold everything together with 8 threaded rods & some alu profiles.
i'll put one bearing to the left and one to the right to hold the axis.

i the meantime i'm still searching for existing alternators, don't know yet what I will do

[folens]

I did some research on a Cross-flow turbine as i read here http://www.otherpower.com/scotthydro1.html
anybody who has experience with this system? I guess the capacity of the creek is about 500gallon/sec and the head is about 1-2 feet

because of the small difference in level i'm thinking to put the nozzle at about 4 o'clock as you can see in the image below



https://www.dropbox.com/s/os4c55q8g3doqvh/turbine.jpg

anyone with experience on this?

Thanks!

[folens]

any other information about number of vanes for the turbine or inclination of the vanes?

i have the feeling i have to make a lot of guesses, experience could help me.

[keithturtle]

any other information about number of vanes for the turbine or inclination of the vanes?

i have the feeling i have to make a lot of guesses, experience could help me.

There's a pdf with Banki construction specifics in this thread, well worth your time, helps you understand the details

http://www.fieldlines.com/index.php/topic,147388.msg1019031.html#msg1019031

Turtle

[folens]

thanks a lot for all the info, the project was a succes, 20Watt, enough for charging radio & phones,


www.youtube.com/embed/Wkh7St80I2A

grtz.
folens

[hiker]

nice vid.    all your dropbox links say--nothing here--
cool little hydro alt.

[bob g]

+1 for the pedgen idea!

what better way to get the attention of young boys as to the realities of electrical production and what it takes to do even the simplest of things like charging a cellphone or a flashlight/torch battery.

when you have to sit on a bike a pedal for maybe 10 minutes to make a 1 minute call, that becomes a life lesson that ought to be learned early on in my opinion.

this is also something that ought to be in their mental inventory anyway, as if the shtf again they would know how to scout up enough stuff to put together a simple pedal powered generator to recharge a cellphone which might be something that might save someone's life one day.

far better to know how to do that with pedal power than with hydro/wind/or solar in my opinion, as none of those resources are guaranteed in all places,  however old junk bicycles or similar can be found just about everywhere, and the generator part can be scavenged out of about any old junk car or similar.

bob g

[sailawayrb]

Late to this party and I have not been a member of this forum...at least not for a very long time...  However, I have been a long time member of the Lister Engine and Micro-Cogeneration forums.  I was also a Scout Master for many years (Boy Scout Troop 455, Renton, WA) and have two Eagle Scout sons.  Anyhow, if you are interested in DIY water work projects (e.g., cross flow turbines, hydraulic ram pumps, pipe/pump systems, water wheels, etc), you may want check out the free DIY design software on our website:
 
{link removed}
[While we appreciate the link and any possible help, our new member rules state no outside links, sorry. You are free to PM it to a member [perhaps Bob G] so they may repost. As a fellow scout I trust you'll understand the rules. Bruce S.]

 
We also have free DIY software for accomplishing building cooling/heat load analysis, engine isolation stand design, hydronic radiant floor heating design, passive solar heating design, pipe/pump system design, pulley system design, psychrometrics analysis and several other areas that may be of interest and value to members of this great forum.  Please be sure to carefully read the instructions for each specific DIY calculator that you intend to use.  If you still have questions, please feel free to use the Contact Us on our website, mention that you are from this forum, and someone will assist you.
 
Keithturtle, our cross flow turbine design software is largely based on C.A. Mockmore/Fred Merryfield, "The BankiWater Turbine", which we also reference in our software instructions.  We have refined the reference methodology to allow designing from a desired turbine speed.  We also added additional parameters to facilitate the fabrication process.
 
Hydrosun, relative to your bearing problems, we highly recommend using acetal plastic for water machine bearing shells in conjunction with SS shafts.  This will result in much longer life than the often recommended ceramic, nylon, or oil impregnated hard wood bearings. Acetal plastic is also a pleasure to machine.  Acetal plastic round can be obtained from OnlineMetals.com in several convenient diameters.
 
Bob G., hello and I trust all is well with you in Kansas!
 
I am very busy these days so I don't know that I will have as much time as would like to frequently hang out here.  So best regards everyone and enjoy!
 
Bob B.

[keithturtle]

we highly recommend using acetal plastic for water machine bearing shells in conjunction with SS shafts.  This will result in much longer life than the often recommended ceramic, nylon, or oil impregnated hard wood bearings. Acetal plastic is also a pleasure to machine.  Acetal plastic round can be obtained from OnlineMetals.com in several convenient diameters.

I have this material for the submerged bearing.   Have not put it into service yet as the dam was washed out in high flow

http://www.vesconite.com/   Don't yet have a report on its effectivness

Turtle

[sailawayrb]

Keithturtle, the vesconite material properties sound nearly identical to acetal material properties.  We have not used vesconite so we can't provide any experienced based comparisons.  However, we have used acetal for hundreds of water machine bearing applications and we have become quite impressed with acetal performcance.  You do of course need to properly size bearing shells based on the bearing material properties and on the water machine loading.

Bruce S, I am not sure what rules you are referring to and I haven't been able to find any posted rules on the site either?  I also see many posted links all over this site, so what exactly made the link to our free DIY water machine design software on our Borst Engineering & Construction website that I posted previously unacceptable? 

Thanks,
Bob B.

[gww]

bob b
I think you need 50 post before posting links and then I don't believe a link for your own commercial intrest is acceptable unless very long and accepted membership. 
Hope this helps
gww

[sailawayrb]

Thanks GWW.  I guess I didn't read the small print when I registered.  It also took four days for my registration request to get approved, so even if I did read it, I would have forgotten it by the time I posted…LOL.  I reckon the rule makers were not aware that the correlation between number of posts and subject matter expertise is strongly negative.  In other words, research has clearly shown that forum contributors with the most posts statistically have the least subject matter expertise.  Or maybe there is another reason for this sort of policy, e.g., protect some people's special interests.  No worries, I only stumbled across this thread and I just wanted to try to assist a fellow boy scouter.  Onward and outward as they say.

Bob B.

[DamonHD]

sailawayrb

I'm hot and tired and probably oversensitive, but I strongly object to the tone of your post.

I'd be astonished if it actually took 4 days to approve your membership; I usually check once or twice a day for new requests and we have to manually screen out the 95%+ of SPAM registration attempts that get though all our other filters.  For which we don't actually get paid big bux.  While taking time away from jobs that do.  For you.  Blech.

Further, the special interests slur is outrageous.  We have the 50 post guideline from some very bitter past experiences.  And actually we do try to bend it where we can, and we discuss most cases.  Indeed, guess what, there is one deliberately left open as a mod issue right now because we're not sure of the right thing to do...

And then, as I think I have one of the higher post counts on this site, you may wish to think what other rudenesses you casually flung around and which actual higher-post-count experts you are dissing.

If you want to come and help, don't p*ss all over the furniture in the communal areas while waiting please.

Rgds

Damon

[Bruce S]

To further what DamonHD has posted, I know very well you did not wait 4 days as I was the one who approved your request.
As a scout, you might want to go back and re-read the pledge. Then come back with a calmer attitude.
GWW, Thanks for the post and your spot on about the 50 posts.
That rule came from the days when dirt was clean, and commercial posts are normally verboten without prior approval from mods or above.

[JW]

Something also, we are not mind readers, even thou you think your user account is plan and simple, Damon is from the UK, so what you are saying is from an American accepted given. its really not and the forum is world wide.

I deleted many accounts for being "purplepasilty" and on other incomprehensible usernames let alone email.

In the past there have been dominate posters but in recently time they are absent. Basically the forum is under the control of the users themselves, rather than dominate users.

We couldn't be happier...

Bruce is in the US soooo...

JW

[XeonPony]

and I find the direct invers to the post count, the ones who have the better post count is becuase they have good working knowledge of the system, it is usualy the one hit wounders that are here to spam or ask a question and forget who they are and never come back, Arogence my friend will cuase many great falls in one's life!

[dave ames]

Thanks for the look folens. 20 watts from a hydro adds up real quickly 

Same problem here with your dropbox we just get the undecideable cube and 'nothing here' message.

Welcome aboard Bob B., Sorry for all the bashing...A pitty really with your impressive CV.

Thanks for those great interactive engineering calculators    nice work there.

Cheers, dave

[folens]

Hi,

previous links are not relevant anymore, i uploaded some new pics from the project that can be seen over here.

https://www.dropbox.com/sh/pl2ijv2m661oukc/fUY4C8wJAm

thanks for the info about plastic bearings but as it only had to work for about 2 weeks, rust was not really a problem.

greetings, folens

[ghurd]

Looks good!
I see you went with a Big motor.
Thanks for the update,
G-