Six of our year 9 pupils at School have just won the east midlands finals with their science and engineering project which is absolutely fantastic, considering the competition they were up against. We being a local comp and the rest mainly from selective and private schools.

However, as a result they now go forward to the national finals in London next year. This means they have to take their project to the next level.(They get 3 days in London fully paid for, and possibly me as well.)

As part of the next stage they will have to make a working wind turbine that will power a pump. This pump will then irrigate the schools organic Veg garden.

I now need some ideas of how to make the wind turbine…Was thinking along the lines of an Alternator being used to charge a car battery. This could then be used to power the pump.

All parts have to be recycled, so old car alternator and Battery would fit.

Any Ideas Or Help Welcome..

Paul

These guys are all but next door to us, always lots of bits laid about, pretty close to you also may be worth a call/visit ? May have some useful pointers particularly on the blade to use, dunno ?

their are plans around to make turbine blades for generators out of drain pipe by cutting em in a certain way.
a permanent magnet generator (dynamo?) would work better as car alternators need power to them to work, so if the battery goes flat itll never get rechared.

why bother with power though? a mechanical pump feeding an elevated reservoir with a drip system would be more efficient.

You'd have to gear the alternator appropriately as they don't produce until about 1400rpm minimum really.

In a car they are 1:3 stepped up approximately - for average cars (it does change with max rpm of the engine, high revvers are geared lower so the max alt speed is circa 18000, above which, all sorts happens inside them and they sieze )

HTH
Stott

[Edited on 8/7/10 by Stott]

saw a really good website with homemade turbine using plastic guttering. gave reasonable power too i remember.

Could you take electrics out the equation, drive a pump directly. fill a tank on stilts and let gravity do the work from then on? just a thought

edit: too slowww again

[Edited on 8/7/10 by dinosaurjuice]

Has to invole power as the first stage of their project was to put the idea forward and build a wind generator that would light an LED to show the principal. Now it has to do its job.

a bicycle hub dynamo would be ideal.

why not build your own dynamo then? that would be impressive! i have no idea how btw. probably involves magnets and coils of wire somehow.


Russ.

What about if you just use the rotary motion of the turbine to drive a shaft thru a bevel gear then belt drive to a waterpump? Might be easier than the electrical solution. Mind you might get more points for combining technologies.

try www.instructables.com for ideas?

Mike

[Edited on 8/7/10 by Guinness]

Best way is purely mechanical ---- crank connected via long co rod to a cross head connected to the piston of a double acting reciprocating pump.

[Edited on 8/7/10 by britishtrident]

Not sure how to do the link:

http://autospeed.com/cms/A_111296/article.html

Homemade bicycle dynamo using an old stepper motor.

OMG! it worked!

The first thing you need to do is work out how much power you need so you can size the windmill appropriately. Bear in mind that a bike wheel dyno might be rated at around 5watts but you won't see that very often.

I have built a few windmills and you might want to look at something like a rewound Lucas AC11 alternator that you can drive direct so no gearbox losses so that you get enough energy (maybe around 125watts at 12volts (10Amp) IIRC)when the wind is blowing to maintain the battery charge and run a small irrigation pump! You will only see an average of around 25watts I expect. PM me if I can be of any help to you!

EDIT

I probably still have the plans for the AC11 mill inc. Jigs for the rewinding of the coils. I know I have enough of the correct wire left to wind at least one more alternator too!

[Edited on 8/7/10 by Strontium Dog]

[Edited on 8/7/10 by Strontium Dog]

How about an electric pump to fill a water tower style system. That way you have stored energy/pressure when the wind isn't blowing. A simple ball cock style switch could stop the pump when the tank is full.

Steve

Nice project.

I think charging a battery is a good way to go, it means you can water on a hot day.

You could add some control circuitry using one of the cheap micro-controllers that are so easily available now.

Something like, measuring the temperature and watering on hot days, watering at night, not over watering, not running the pump when the battery is low, or when there is no water to pump.


I suspect these things would all appeal to a judging panel and are easy to implement. Look for example at
http://www.coolcomponents.co.uk/catalog/product_info.php?products_id=335&gclid=CN3I3afk3KICFYGX2AodzUjgYw

The Arduino boards are amazingly cheap and easy to use.

Matt

I have some stepper motors if you want to try that method or if you want magnets I can supply you with either samarium cobalt (very powerful) or Neodymium (most powerful). I also believe we have a coil winding machine at work but I've never used it.

drop me a U2U if you want anything

quote:

---

Originally posted by matt_gsxr
Nice project.

I think charging a battery is a good way to go, it means you can water on a hot day.

---

must say, including a microcontroller would add a level of excellence to the project - worthwhile if you can do it. Maybe just to control the pump switch to have the tank full first, battery full second.

A tip though, keep the water tank as close to the height of the plant pots as possible to minimise how much work the pump needs to do!

you need the motors from an old real to real tape deck


[Edited on 8/7/10 by graememk]

A year ago I saw a program on Discovery were they built a piston pump for irrigation and drinking water for cows.

If I remember correctly the used a piston pump. Purely mechanical.




The driving rod was connected to the wind turbine with a simple crankshaft mechanism to convert circular movement to linear movement and it worked quite well !

The blades were made of aluminum sheet. Possibly you can also pump the water to a higher positioned tank so you can still irrigate when there is no wind.

I've a photocopy of a project called called "Scrapyard Windpower".
Can recopy it for you.

I also think converting movement to electricity and back is a bit of a waste. Makes more sense to just power a pump via bevel gears.

Now the genius way to water stuff is to use a clack valve. That's plain crazy.

Ummm shouldnt the kids be thinking up ideas? I guess the paid invite doesnt extend to any of us???!!!

I saw a hotel on one of the Cayes in Belize where it was purely powered by a wind turbine which was home made.

He used the tail rotor off a helicopter coupled to a 90amp alternator (off a FFR Landrover) this then charged a bank of batteries and everything in the hotel was either 12 or 24 volts, very clever and not that expensive to set up as he got everything from the dump at the British camp .

A good few years ago, I took the kids to wales for a holiday (wait for it ). We went to this place which was all about green, organic etc.

They had a wind pump which was so effective it could lift a couple of people sitting on a seat attached to the pump arm. Looked a bit like those things with lots of wind vanes scattered across the USA. Can't remember the name of the place but I'll try and find it.

No need to worry about batteries/charging etc.

Just a thought....

JB

http://www.southcom.com.au/~windmill/info.htm

Hugh

A squirrel cage fan type rotor is less dependent on wind direction.

Hi

Isn't a squirrel cage type a non self starter?

Regards Mick

Thanks fort all the replies. Will have a think and get back to some of you..

Cheers

Paul

Without any guidance the Kids have evaluated thier options after dsicussing the needs of the garden with its manager. THEY have decided that they will work on a wind generator that powers a growth lamp during the winter months and a pump during the summer.

So I am just keeping ahead of them so that when the ask for parts I can provide them.