Author Topic: Artesian Well Generator (Read 20747 times)

Ken · « **on:** March 17, 2005, 04:32:56 PM »

Hi

I have an artesian well with .1333-.26 L/sec (2-4 Gallon/min) flow and a Head of approx 50 Meters (160 ft). I am looking to build/buy a Pelton wheel or (Similar) to get approximately 50W-100W of power.

I don't have a clue as to what I need in th way of

a) Motor/Windings/RPM specifications

b) Adapter size (Water flow)

c) Where to get a pelton wheel (Or build one cheap)

d) Power shunt (What kind of controller/shunt is required and where can I get the specifications for a design ?

The output pipe has already been run

(1.5 " Flexible Plastic, high pressure piping (Blue))

Alot of questions I know...

First Posting ... Anxious about the potential....

Ken

Gary D · « **Reply #1 on:** March 17, 2005, 09:45:57 AM »

Perhaps a link....

http://www.harrishydro.com/determine.htm

Gary D · « **Reply #2 on:** March 17, 2005, 10:14:14 AM »

Obviously you'll need to make a homebrew becouse none offered will produce at your flowrate and static head. His generators are 30 to 70% effecient (and 2"piping for less friction working head). Perhaps one of the numbercrunchers here can advise... Gary D.

Ken · « **Reply #3 on:** March 17, 2005, 01:09:17 PM »

Yup. I already look at the harris pelton stuff but needs too much flow.

The only thing I could find so far was a 300 watt generator from a company in Rainbow Power Corp in Australia (Water Baby)

http://www.rpc.com.au/products/hydropower/HYD-200-Manual.pdf.

They have a unit that will run on as little as .1333 l/sec (Exactly what I have now...). Unfortunately well over my price range for a 50 watt generator.

I am willing to make a homebrew if someone can point me in the right direction for the specifications I need.

Flux · « **Reply #4 on:** March 17, 2005, 03:36:21 PM »

Not that easy to make a pelton unless you can get the buckets cast. I think you would do better with a rotor much larger than the Harris say 12" diameter. The lower speed would enable you to couple it to a very efficient dual rotor air gap alternator.

You have little power to spare so I would not use iron in the alternator.

You may manage to get a Banki to work well enough but your head is rather high. It would be much easier to make than a pelton. I couldn't say how well it would work under these conditions but it would be fairly easy to make. It may even work with the nozzle positioned on the inside directed outwards so it is only one stage, something like a radial flow turgo.

Flux

Ungrounded Lightning Rod · « **Reply #5 on:** March 17, 2005, 03:52:46 PM »

A Banki/Mitchell crossflow turbine is a LOT easier to construct than a pelton wheel. A Banki is just curved blades between two disks on a shaft, inside a housing you can bend and weld up from sheet metal. Easy to design, easy to fab, easy to balance. Wide inlet and outlet openings and flow guides, so flow is pretty unrestricted. The pelton has a jet (more clog risk) and buckets with compound curves (which you pretty much have to cast).

The pelton's efficiency is about 90% and pretty flat at flows from maybe 20% of design flow to max. A banki is about 80% efficient from about half to full flow, but slopes down a bit below half the design flow.

With an artesian well your flow should be pretty stable and trash-free. If you don't feel like making your own rotor you might be able to use a small squirrelcage fan's rotor as a ready-made approximation of the right structure.

I don't have the rules handy but I'd guess that at 2-4 GMP the turbine ought to be significantly smaller than a soup can. (Small is good because you get high RPM.) You can get a hysterical amount of energy from a very small water turbine.

Note that if a water turbine is sealed well it can work below atmospheric pressure. This means you can mount it somewhat (a few feet) above the output of an outlet tube, with the tube below a water surface to prevent air coming in and breaking the suction, and still get the advantage of the head down to the output water surface.

Hank · « **Reply #6 on:** March 17, 2005, 04:41:39 PM »

With 4 gal/min and a 160 ft head you may only be able to extract about 15 watts of power.

HAve fun,

Hank

Peppyy · « **Reply #7 on:** March 17, 2005, 05:11:38 PM »

Even though it is only 4/gpm if you have 150 feet of head I would think you would be able to build a lot of pressure. If that pressure was released by a 1'4 inch nozzel the resulting stream would be really strong. I heard somewhere of a high speed turbine that didn't need a lot of volume but used high pressure.

I am most likely way off on this but I know that a garden hose nozzel at 40psi can really spin things. It is a thought anyway.

Hank · « **Reply #8 on:** March 17, 2005, 07:17:59 PM »

Oops,

Stand corrected should be 50 - 70 watts.

Running 24/7 may be worth it or at least fun trying.

Hank

healerenergy · « **Reply #9 on:** March 17, 2005, 07:29:06 PM »

Mother earth news had a home made hydro in one of its artical some time back might be worth a look.

jimovonz · « **Reply #10 on:** March 18, 2005, 01:29:00 AM »

I purchased pelton cups from www.ecoinn.co.nz and they work fine. Freight may make these too expensive for you. You have to size the nozzle you use to match the flow/head you have. If your nozle is too small you loose water out the top of your collector, if its too big your water level drops in your pipe and you loose head. Here is a table for working out nozzle flow: http://www.mayflowertrading.com/hydro_5.gif. Once you determine the nozzle size you can work out the speed of the water leaving the nozzle - flowrate in l/s divided by nozzle area in mm2 times 100 will give you m/s. Max efficiency is reached when the pelton cups are running at 1/2 the speed of the water jet. I would recomend that you build an alt first so that you can size the pelton wheel to match this speed. Once you know the power curve of the alt you can calculate the diameter wheel required to make the desired amount of power while keeping the cup speed at 1/2 nozzle velocity. I would work on an overall efficiency of 50%. As an example I will assume that you have 0.2 l/s with a 50m head:

Expected Power: H(ead) x F(low) x G(ravity) x E(efficiency) = 50x0.2*9.8*0.5=49w

Static Pressure:5 Bar (73psi)

Nozzle Size:2.9mm (extrapolated from table)

Nozzle Velocity: 0.2/(3.14159*(2.9/2)^2)*100=3.03m/s

Say our home brew alt makes 50w into a 12v battery at 180rpm (3 rev per sec):

Optimum wheel tip speed: 1/2x3.03=1.5m/s

Optimum wheel diameter: 1.5/3/3.14159 = 159mm

The wheel diameter is measured at the centre of the cup (where the jet hits). In your example you can practicaly ignore friction loss in the pipe as you have relatively low flow in a large pipe. The loss is around 0.05psi/100ft pipe

I can't be much help for the alt as I have never made one with a view to optimising it for 50w. I would definately go for an air core, dual rotor. Take a look through the board at the various setups and power figures. As for a controller, I presume you are going to be charging a relatively small battery and are looking to prevent overcharging. There are plenty of charge controllers around that would do this for you or it would be quite simple to make up a circuit that disconnected the battery over a preset voltage. The turbine won't care wether the load is connected or not, though it may become rather inefficient if it is loaded down too much (depends on your alt). If you really wanted to get the most from the turbine you could use/build a max power point tracker. A really simple way of getting into building a controller yourself would be to look at the picaxe micro at www.picaxe.co.uk

I found making the turbine reasonably straight forward and great fun! I have 1 l/s flow and a 30m head. I get good efficiency (~80%) as I direct drive a pump (very efficient hydracell G-03 www.hydracell.com) I started out generating electricity using a smartdrive motor but it was going to cost too much ($ + efficiency) to get the power to the house 1500ft away. It would have been fine if the house was closer

Gary D · « **Reply #11 on:** March 18, 2005, 07:26:20 AM »

Ken, not sure of your location, but you might look at a place out of Utah for pelton parts (wheel and such). I've never done business with them. If you are up to experimenting with a

homebrew alt. this might be one place to get parts. If you are in Australia, I'd try the site you posted a link to(may sell the wheel and shaft separately).

Anyways, always neat to look around a microhydro site ;-)

Good luck, Gary D.

http://www.h-hydro.com

DERFMOOSE · « **Reply #12 on:** March 18, 2005, 11:29:45 AM »

I saw a articale where they used spoons for wheel cups

don't know how well it worked but you can have fun tryin

derF

Flux · « **Reply #13 on:** March 19, 2005, 01:02:54 AM »

Had similar thoughts myself, they are about the right size for this one.

Flux

Ken · « **Reply #14 on:** March 19, 2005, 09:10:35 AM »

Thanks

I finally found a site that offer a formula to calculate optimum Wheel sizes for Pelton/Turgo wheels and also provides for optimum RPM calculations for the motor generators. http://h-hydro.com/impulse.xls

Thanks for pointing me to the site for Pelton wheels !

So, from the site feedback and a review of this chart it appears that my ideal #s would be

Nozzle diameter 2.3 mm
9 cm Diameter pelton/turgo wheel

RPM 1806

Peak Power Jet 31.3 m/s

Runner Velocity 15 m/sec

These figures are off by a factor of 10 to those supplied earlier.

I am assuming the spreadsheet I found above is correct and the figures supplied were a simple numberical calculation error.

OK So all I need now is how to build/find a motor that has these power specifications ?

I/E. 50 Watt @ 1800 RPM

Looks like a pelton/turgo can be purchased @ http://www.h-hydro.com/ if I select a 17 spoon 155.3 mm diameter wheel. for $240.00 (Ouch !!)

It should result in a Effective RPM of 1812 (Within 6 RPMs of optimum....)

Note: This works to 30 REVS/SEC so I don't think the plastic spoon home build plans will be applicable.

Anoyone point me in the direction of this motor ?

TO purchase or to make ...

If someone could also verify these specs it would be great !

Hank · « **Reply #15 on:** March 19, 2005, 10:09:44 AM »

Kind of a tiny nozzle. One grain of sand and you're out of business.

Perhaps you may want to consider a PM dc motor driven by your turbine to produce power.

You are only talking about 1/16 hp.

Just a thought,

Hank

Flux · « **Reply #16 on:** March 19, 2005, 11:18:24 AM »

Turbine figures look reasonable, I did it my way and came up with 1600 rpm for a 6" runner. Don't expect these figures to be more than a ball park figure, water doesn't work that way.

To give you something to start from, if you use 8 magnets 3/4" x 3/4" x 1/2" on a nominal 6" disc and another disc rotating but with no magnets on it, with coils about 5/16" thick you are looking at about 30 turns per coil with 2 coils in series per phase.( 6 coils total).At a guess 2 parallel 1mm dia wires should be ok and easier to wind than a single thicker one.

At that speed you will have to place the magnets accurately for balance and make a good job of sticking them on and pot them well to prevent corrosion in the wet conditions. Make provision to alter the gap between the magnet and the plate to get its load right for the turbine.

You may also be able to find a suitable dc permanent magnet motor such as an amtek but I have no idea of their efficiency.

Flux

Ken · « **Reply #17 on:** March 19, 2005, 11:22:03 AM »

http://shop.emotorstore.com/estore/product_dcm.asp?pf%5Fid=6976&dept%5Fid=6042&

Found this motor but not sure how well it would work.

12-24 v DC 1700-4200 rpm.

Any feedback would be appreciated.

Note: What voltages/current would i expect to get from this motor @ 1800 rpm and 3600 rpm ?

Ken · « **Reply #18 on:** March 19, 2005, 11:26:42 AM »

http://shop.emotorstore.com/estore/product_dcm.asp?pf%5Fid=6976&dept%5Fid=6042&

This is a motor I found that I think migh make the bill...

Not really sure how I can relate my output to dc motor specifications.

I just tried to match them up 1-1 ?

As for the small 2.3 mm nozzle.... What are my alternatives ?

Any suggestions to reduce clogging likelyhood ?

My power originates from my head not the flow (Unfortunately..)

Hank · « **Reply #19 on:** March 19, 2005, 12:02:33 PM »

Ken,

I'm not sure about the efficiencis of these.

I would not expect you to get much more then 3-3.5 amps at 12 volts and half of that at 24 volts.

You only have about 50 watts of power available to you.

Now if you could increase your flow..........

Hank

Vernon · « **Reply #20 on:** March 19, 2005, 12:57:41 PM »

I would use an automotive alternator fan as a pelton turbine and have it drive an automotive alternator. I would simply turn the fan over and space it out so that it had some space between it and the alternator body, make a nozzle out of 3/8 inch steel brake line tubing, work out an optimum aim .. provide some sort of barrier to keep splash off the alternator and let it rip. 4 gallons is about 32 pounds of water a minute or .53 pounds per second and dropping through 160 feet is about 85 ft pounds per second, .15HP or around 115 Watts. Not much energy and the alternator field would use a chunk of that, since the energy is low it is not worth having a large capital investment in some fine tuned PMG based custom system. The best way would be to use cheap junkyard stuff and get a stock tank to store water at the well ... fill the tank, run the auto alternator in 700 watt bursts to make it worth applying the field then store that energy in a battery.

Ultimately you could weld small pieces of sheet metal on the "turbine" to box it in and increase efficiency ..... but it would work well enough as it is.

Peppyy · « **Reply #21 on:** March 19, 2005, 03:43:59 PM »

Let's look at this store and generate method.

If we say that in continous mode we get 60 watts with 4 gallons per min that works out to 15 watts per gallon right?

How many watts can you generate with 8 gallons per minute?

If you can make 200w at 8gpm you are now at an average of 100 watts continous

when you factor in a 50% run time.

I am not a math wiz so I am probably completly wrong.

Vernon · « **Reply #22 on:** March 19, 2005, 08:06:06 PM »

I am for the "duty cycle" method using a tank or 2 - 3 55 gallon drums to hold water. Given the same head doubling the flow rate would double the power. An automotive alternator with integral regulator can easily produce 700Watts at a nice constant 14.2V. With a PMG you need a custom one off design matched to the installation and it seems to be a lot of work and money ... you can get an alternator at "pick a part" for 20 bucks and mount it with a couple of bolts. It could be installed with the shaft vertical on top of a steel "water box", the inverted spaced alternator fan will work well enough as a prime mover and if you want max efficiency you can have a pelton wheel made at some point.

Ken · « **Reply #23 on:** March 20, 2005, 05:59:53 AM »

Fantastic Idea, to use the Alternator Cooling fan as a imitation Pelton !.

I think this idea has merit, and may work.

Unfortunatly, the storage tank idea doesn't apply in this scenario as the pressure comes from an artesian well not from being elevated and falling the "Pseudo 160 ft".

The storage tank (c.w. air bladder) would only create a buffer against momentary changes in pressure and flow to create a more stable pressure.

Would the alternator still function properly without a larger flow ?

What happens if the current draw for charging increases above the ~ 4 amps being generated by the alternator. Would this slow down and possibly stop the alternator from turning or would it simply continue to charge at the 4 amp rate ?

Note: Should I look for the samllest alternator possible ? I have seen some at a really cheap price $35.00 that provided a maximum of 35 amp charge rate ?

What would you recommend ?

Hank · « **Reply #24 on:** March 20, 2005, 07:03:45 AM »

Consider this,

Using the alternator fan to drive the alternator in all probability will yield a very low efficiency.

So that theoretical "4 amps" may fall down to 3 or less amps.

A car alternator needs external power to excite its field. Where is this power going to come from?

Either from a battery or from the power of the alternator. You may in fact find that you will need more power to excite the field then your system can produce.

If more current is needed more power is applied to the field and it will in all probability stall the alternator if using a standard regulator. Of course you could build some kind of regulator to compensate for all of this so it will only put out the available power.

On the other hand using a PM alternator does not require external power to be able to generate electricity.

Have fun,

Hank

Hank · « **Reply #25 on:** March 20, 2005, 07:10:40 AM »

Ken,

Might be a good site for you to review.

http://www.otherpower.com/otherpower_wind_alternators.html

Ken · « **Reply #26 on:** March 20, 2005, 08:40:06 AM »

Thanks Hank

What do you think of the idea of a squirrel cage to a DC motor like

http://www.surpluscenter.com/item.asp?UID=2005032008313450&item=16-1257&catname=electric

Its cheap, and in effect ready assembled.

I think I would only have to "reduced the width of the squirrel cage and vola, ready made !. Even made out of durable plastic....

Would this work ?

Ken · « **Reply #27 on:** March 20, 2005, 08:42:57 AM »

http://www.surpluscenter.com/item.asp?UID=2005032008313450&item=1623&catname=electric

One more to comment on.

Seems like better specs and only $6.

Hank · « **Reply #28 on:** March 20, 2005, 09:33:28 AM »

Ken,

This may be a better approach?

This will approach a Banki/Mitchell type of turbine but will probably not get the rpm's of a Pelton.

In the first blower/motor combination it calls for 3500 rpm at 12 volts. You will have to get about 4200 rpm to start charging a battery (you will need about 14.5+ volts for battery charging).

No rpm specs on the second one so I can't tell.

Perhaps using the squirrel cage set up with a different DC motor would be doable.

Threadmill motors are usually DC rated at about 100 volts at 4500 rpm. Using a motor like that it would start generating charging power at about 650 rpm. You can find these things at scrap yards (I have 3 of them). Perhaps Amtec motors would work out as well but I'm not familiar with them (check other posts).

Of course you could always build your own, that would probably be the best option but would require work on your side but you could match it to your conditions.

Check this site where one was built.

http://www.otherpower.com/otherpower_hydro.html

By the way you stated that the 150 ft head was not really a head but the equivallent? what do you mean by this? Do you have about 75 psi at the well source? What will you do with all the water? 4 gallons per min. is a lot of water over time. Make sure you don't run the well dry, especially if others are on the same vein.

Hope this helps and be carefull this stuff is very contagious,

Hank

Vernon · « **Reply #29 on:** March 20, 2005, 10:49:38 AM »

I was not aware of this being well pressure ! I had assumed that the water sprung from the side of a hill somewhere. The large sealed tank with compressed air would work but that is expensive for the energy available. I think you need at least 300 watts of mechanical power to make an auto alternator worthwhile because of the field energy required. A PMG has to be carefully matched to the system to take advantage of all the theoretical gain of field loss elimination. Car alternators are cheap enough so I would try that first and figure out a way to build a cheap hydraulic accumulator so you can run the thing in "spurts". Perhaps a few vertical 10 foot legnths of 6" PVC pipe would work. While the water was off air would be compressed in the top of the pipe and that energy would be released when the water valve opened.

The car alternator needs maybe 30 to 40 watts to excite the field so is very inefficient if you only get 100 watts total, the 35 AMP unit you mention should be better in that regard, I was thinking 50 AMPS. In pulsing the unit the field would be turned on only when water was flowing and high power generated.

Another thing to consider would be a tape drive motor (if you can find one)or some other surplus permanent magnet motor that will produce 12V (8-10A) at around 1500 RPM and an alternator fan as a turbine.

Ken · « **Reply #30 on:** March 20, 2005, 12:47:04 PM »

All of our neighbours have artesian wells, (Last 30 years) all sourced from the same aquifer. I assume is is being supplied by the up river dam (1.5 miles) upstream. It's a hydro quebec power dam and it is about 100 ft high.

I don't think there is any worry about running dry as it comes from the ottawa river (200km long) and .5 miles wide...

Still trying to think of a way to harness the river (Slow flowing (Negligeable head) but HUGE flow)) .5 miles wide and 150 ft deep.

That going to be a new listing....

I'll see if I can source another motor a little closer to the specs you mentioned..

Nando · « **Reply #31 on:** March 20, 2005, 07:28:33 PM »

Ken:

Your site may produce 0.133 * 50 * 6 = 40 watts - expect 30 to 60 watts or 0.72 to 1.44 KW H. ( 0.133 to 0.26 l/s )

Where are you located ?.

I have a small Turgo made by RPC that may be used there, and just using a small PMG generator.

If you are interested let me know

Nando

Ken · « **Reply #32 on:** March 21, 2005, 09:23:51 AM »

Hi Nando

I am located near Montreal, Quebec Canada.

News:

Author Topic: Artesian Well Generator (Read 20747 times)