Pelton Wheel

[Mark Segna]

Hello to all,

I am new to this so please bear with me. First, a little about me. My wife and I have a small home on 15 acres in the mountains of Westren North Caroline.
There is a nice creek that runs through our property that some time back ( 1991 to be exact) I decided to put it to work for us. I started looking at turbines of every type and decided on a pelton wheel. I could't find much info back then but then I ran across some plans I think came from an old Popular Mechanics magazine. Anyway, I built one with a few mods of my own.
It took me 2 years to to build the whole system and on Jan. 1993 I was up and running and off the grid. :D
I have 32 feet of fall from intake to turbine. ( don't ask how much flow. I don't know) All I can tell you is the intake is 6" pvc for the first 360 feet and then steps down to 4" for the next 190 feet with a 1 1/2" nozzle on the end.
I am using a 3phase PM brushless alternator. It's output is held between 150 & 200 volts AC. This is then rectified and sent to a switch mode regulator and charges the 12V battery bank. I can produce 30 amps DC 24/7/365
I've attached a few pictures of my system. First the wheel itself, then the whole unite running, and the load control I built that dumps excess power into a bank of light bulbs.
I've had a lot of fun building this and watching it work over the years. Hope to hear some feedback on this thing. Maybe some improvements?
I do have some questions on a new alternator to throw out to everyone.(maybe on my next post)
KEEP IT GREEN

Mark S.

[Rob Beckers]

Hi Mark,

Welcome to Green Power Talk!
Ah, the North Carolina mountains... I spent 12 years in Durham, NC, and visited the mountains many times. Beautiful area!

Great water turbine you have there. Being able to charge at 450W and do that 24-7 is pretty well the holy grail of RE (that makes around 10 kWh per day!). What are you using as an alternator? Is this home-made, or commercially available? You mention using a PWM regulator to charge the batteries, going straight from around 200V down to 12V; I wonder if a true buck controller would be more efficient. They use an inductor, which in essence transform the voltage down. If your controller works as I imagine it would essentially 'short' the alternator, rather than convert the voltage efficiently.

-RoB-

[Mark Segna]

Hello Rob,

Thanks for the compliment on my toy. As to your questions. The alternator is made by Thermo King. It is a 3 phase PM alternator 240 volt 60 Hz 3.7 KW. As far as I could find out it was built for a auxiliary power unit for trucks. I got it from a junk dealer in the area that didn't know what it was but then, neither did I. I have tried to find another one but with no luck at this time.
The armature in it is stationary and a drum with the magnets rotates around it. The shaft in the back is hollow where the wires from the windings come out. It had a 2 groove pulley on the front that I machined off and made an adapter to hold a 35 roller chain sprocket. The chain drive is 7.5 to 1 and runs in a inclosed mineral oil bath. The sprockets are hardened tooth. No signs of wear yet! I have another picture of the turbine showing the alternator at an angle. You can see the armature inside.
As for the controller, all it does is clamp the power coming from the alternator. It loads it down to keep the turbine from over speed. It turns on lamps in stages as the batteries reach full charge. The switch mode battery charger is self regulating and will accept either 120v AC or high 150v to 250v DC input. Hope the helps.

Mark S.

[Rob Beckers]

That alternator is quite a scoop! Those things are not easy to find, nor cheap. You mention overspeed: Isn't a Pelton wheel a drag device? So, it can't really overspeed because it'll move no faster than the water flow over it (?).

-RoB-

[Mark Segna]

Sorry about that Rob, I should have said keep the alternator from over speed. I don't know what kind of rpm the alternator can stand, but I like to keep the output down to 200v. Being that it has a 7.5 to 1 gear up If I were to completely unload it the rpm go out the roof. Also, I have filters on the DC side that are only rated at 250v. I don't want to push them any harder.

On the subject of alternators. Have you had any experience with the Fisher & Paykel washing machine motor? I came across a couple of these and I was considering trying one. My concern is that they are made of plastic and wondered if it could stand up to 24/7 operation. I have read that some guys are using them on wind turbines but the wind doesn't blow all the time. My understanding on this motor is that leaving the winding as they are, you can get 200v without real high rpm. If so, I could gear down and maybe get a little more HP out of my turbine. Any input would be greatly appreciated.

Keep It Green

Mark S.

[Dennis Buller]

I do not have any experiance with those types of generators, but this fellow seems to be the expert on it. He is in New Zealand.

http://www.ecoinnovation.co.nz/

[Mark Segna]

Thanks for the link Dennis.
Looks like this guy does a lot with this motor. I'm going to contact him soon and find out all I can about it.

Keep it Green

Mark S.