Author Topic: Options for Wind-Electric Water Pumping  (Read 10382 times)

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cslarson

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Options for Wind-Electric Water Pumping
« on: March 12, 2008, 04:27:06 PM »
(This posting is somewhat of a follow-up to a 2005 posting: http://www.fieldlines.com/story/2005/7/30/563/12423)


The well depth is 150m with a reservoir 20m above that on a hill. The location of this well is a land-reallocation site for returning refugees in Afghanistan (450 homes). The ngo installing the pump is planning to power it with a diesel generator at a cost of approximately $12,000/year. They are offering to pay the first year, after which the Afghan government is supposed to provide fuel. The likelihood that that will occur is almost nil.


We have developed a wind turbine with a 4-meter diameter rotor. These units will eventually be sold for somewhere between $1500-1800.


A company called AeroVironment sells a "Universal Solar Pump Controller", the USPC-5000. I've received a quote of $5500 for this device. They state that it is a "variable speed motor controller" so I think it must be some kind of specialized vfd (variable frequency drive, ac drive). It can drive standard AC water pumps up to 5kW in size. Would it be possible to combine the rectified output from a number of these 4-meter wind turbines to power a water pump for this well with this unit? Are there any similar competing products available?


Other than batteries+inverter what other options might be suggested? I have not found dc water pumps larger than about 2kW.


Could a standard variable frequency drive somehow be employed if the dc buss was accessible and the combined output of the wind turbines could be made to reach the dc buss voltage?


I believe an affordable water pumping solution could have a great impact here. Any suggestions are much appreciated.






Photos would not display so I clipped them out to clean up the post.

« Last Edit: March 12, 2008, 04:27:06 PM by (unknown) »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #1 on: March 12, 2008, 10:39:18 AM »







i apologize for the photos not working in the original post.

« Last Edit: March 12, 2008, 10:39:18 AM by cslarson »

feral air

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Re: Options for Wind-Electric Water Pumping
« Reply #2 on: March 12, 2008, 02:51:43 PM »
Instead of (or as well as) wind, you might look into growing an oil crop. If they're getting the water free for the first year then maybe some could be used to grow the fuel that'll be needed next year.


I know that's not the answer you were looking for but it's a thought. take it easy

« Last Edit: March 12, 2008, 02:51:43 PM by feral air »

wdyasq

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Re: Options for Wind-Electric Water Pumping
« Reply #3 on: March 12, 2008, 04:22:59 PM »
I 'think' a 5kW VFD should work - IF it is supplied sufficient power. I 'THINK' one could use inexpensive inverter(s) to boost a battery bank to proper voltage and use a 'hacked' VFD unit.


Good Luck,


Ron

« Last Edit: March 12, 2008, 04:22:59 PM by wdyasq »
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oztules

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Re: Options for Wind-Electric Water Pumping
« Reply #4 on: March 12, 2008, 04:36:25 PM »
Cheapest way would be with a ebay 3phase ups such as this little 30kw unit in Texas....


http://cgi.ebay.com.au/Liebert-AP340-UPS-System-30KVA-3-Phase_W0QQitemZ380004102694QQihZ025QQcategor
yZ44963QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


......oztules

« Last Edit: March 12, 2008, 04:36:25 PM by oztules »
Flinders Island Australia

Drives

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Re: Options for Wind-Electric Water Pumping
« Reply #5 on: March 12, 2008, 06:56:00 PM »
Ron's option is one of 2 that will work.


The VFD (another label is AC Drive)  needs a stable DC source to feed the DC Bus inside of it.  


The output of the wind turbine fluxuates in voltage ultimately based off wind speed.  

To create a stable DC source, one would need to feed a battery bank with the turbine output, then connect an inverter to the battery bank.  The inverter would feed the stable AC input voltage to the VFD.  The VFD would drive the pump.  The obvious problem is all the conversions of voltage,AC to DC to AC to DC to AC causes much waste.


The best solution is to have an unconventional wind turbine that generates a high voltage DC.  In the example above, it was assumed the wind turbine was a typical 48VDC unit.  

For the best solution, we would need to connect the turbine directly to the battery bank, and connect that directly to the DC bus of the VFD.  The difficulty is the fact that for a 208 VAC VFD the DC bus must be a stable 294 VDC.  The formula to convert 3 phase AC to DC is


VAC ave times the square root of 2 = VDC


I have done something similar when we made an electric car and used 24 qty 12 VDC batteries connected in series to feed a VFD controlling an AC motor.


And yes, most 5KW VFDs (round up to the next size HP...7.5HP) do have the DC bus terminals available for direct connection.

« Last Edit: March 12, 2008, 06:56:00 PM by Drives »

Drives

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Re: Options for Wind-Electric Water Pumping
« Reply #6 on: March 12, 2008, 09:41:34 PM »
I thought of another possible solution, but I have not tried it before.


The 3 phase pump motor needs the voltage and frequency ratio to match as you change speed.  Meaning if you have a 208VAC motor rated at 60Hz and you wanted to run at half speed, you would feed the pump motor 104VAC at 30 Hz.  At 1Hz you would feed the motor 3.47VAC.  


Why not design the wind turbine to provide this exact ratio of voltage to frequency directly to the pump motor.  If the wind speed is slow, you may have problems pumping against such a large head.  However, if the wind was blowing hard the pump would have all the power the turbine could provide with no loss in any voltage conversions.


Because you do not want to "store" water rather than electric power this may be a way to not need the VFD or batteries all together.


Just an idea to try.

« Last Edit: March 12, 2008, 09:41:34 PM by Drives »

Drives

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Re: Options for Wind-Electric Water Pumping
« Reply #7 on: March 12, 2008, 09:50:30 PM »
That last sentence should read "because you DO want to store water rather than electric power, this may be a way that does not need a VFD or batteries"

I'll go back to sleep now.  LOL
« Last Edit: March 12, 2008, 09:50:30 PM by Drives »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #8 on: March 12, 2008, 10:42:24 PM »
Thanks for your comments. Because of your previous posts, I was hoping to get your input. I think the last solution would be ideal. The Agricultural Research Service of the USDA has done some work with this type of solution and I've included a few links below. LIke you suggested, a controller is needed to ensure a constant V/f ratio and control some on/off points for the motor. I have not found, though, any controller like this that is commercially available. I did get part way into developing my own, but have since taken a break from it to finish the prototype 4-meter wind turbine (also, my electrical engineering skills are severely limited). The problem with this approach, though, is that the wind turbines we're producing are too small independently the water needed from that depth. If I were to use these turbines I would need to combine the output from a few of them.


I think we can rewire the alternators to achieve higher voltages as needed. I am interested in your #2 option (turbine>battery bank>dc bus of vfd). These would need to be deep cycle batteries? If there was a way to configure the vfd to only use the amount of power that the wind turbines were putting into the bank then maybe the expensive deep cycle batteries would not be needed. Or maybe at least not as high Ah ratings. I mean, only power the pump when power is coming in, and then, only to match (slightly under) what is coming in. How would I regulate this? I guess I had been sizing the battery bank for the pump like you might size one for any other appliance, giving sufficient Ah capacity to ensure power is provided for some time when the wind isn't blowing. But there is a large reservoir for the water. Much, much less might be spent on the batteries if the pump were only to be powered when the turbine is producing, and hopefully, somehow, to match that output. That may have been obvious to everyone else!


Cheers.


1996 A Smart Controller for Wind Electric Water Pumping Systems


2000 Development and Testing of a 2-Kilowatt Wind Turbine for Water Pumping

« Last Edit: March 12, 2008, 10:42:24 PM by cslarson »

Flux

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Re: Options for Wind-Electric Water Pumping
« Reply #9 on: March 13, 2008, 01:59:46 AM »
I think much will depend on the type of pump as you are lifting the water a long way.


If this is some form of positive displacement pump then you have a far better chance. If it is a high lift centrifugal then you may not be able to reduce the speed much before it fails to deliver against the head. This would impose serious problems with other than full wind days.


Assuming that you have a positive displacement pump then the idea of matching the frequency of the turbine to directly drive a motor is the ideal one but it does cause you serious problems if you want to use more than one turbine feeding the motor, I seriously doubt that they could be held in synchronism.


Feeding dc to a vfd seems simple in theory but you would need a fair bit of circuitry to hold the volts within limits. You will also need a supply for the drive control circuits.


It is likely that you will be forced to use a standard unit and modify it. Otherwise starting from scratch I think a vfd could be produced to accept a dc rail that rises with the motor speed just as the motor will accept raw ac as long as it varies in voltage and frequency in the correct ratio ( which it does in this case).


Unless you can interest someone with considerable knowledge I suspect you are going to struggle. Going the battery and inverter then vfd route will work but the losses are going to be high and the cost penalty of the batteries probably makes it not viable.


Seriously worth thinking about using more smaller dc pumps but again this could be impossible with a bore hole.


Flux

« Last Edit: March 13, 2008, 01:59:46 AM by Flux »

dinges

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Re: Options for Wind-Electric Water Pumping
« Reply #10 on: March 13, 2008, 02:13:47 AM »
"I believe an affordable water pumping solution could have a great impact here. Any suggestions are much appreciated."


Have you considered using a water-pumping windmill ? As used to be common in the countryside in the USA and Australia ? The many bladed slow runner variety.


I'm not familiar with them and don't know if they can pump water up 150+ (170+) m, but it sounds like a much more elegant, simple solution to me than electric pumps, batteries, inverters, VFDs, etc. No electrons involved. 'Simple' technology like this may mean it continues to work, be maintained and repaired by the locals after the NGOs leave...





Peter

« Last Edit: March 13, 2008, 02:13:47 AM by dinges »
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ruddycrazy

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Re: Options for Wind-Electric Water Pumping
« Reply #11 on: March 13, 2008, 04:06:29 AM »
As an alternate approach why not use compressed air to raise the water. I've read on previous research the air lift system designed properly can raise water 500' at a reasonable rate. If your interested I can upload the documents I have onhand here to my website for a short time so you can download them. I modiefied an old lawnmower motor into a compressor and I reckon a 44 gallon drum savvy genny would power it nicely. Something of this nature could be scaled up or alternately store the power of the wind gennies in a batterybank and use an inverter to power an air compressor.


Cheers Bryan

« Last Edit: March 13, 2008, 04:06:29 AM by ruddycrazy »

zeusmorg

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Re: Options for Wind-Electric Water Pumping
« Reply #12 on: March 13, 2008, 05:03:48 AM »
  It is probably a problem based on how much volume of water you do need to pump, which you don't state.


  Grundfos makes a helical rotor deep well pump capable of delivering 2 GPM. It's their sqf-3 model. I believe it's around 1,500 usd.


  A windmill based solution is possible. Aeromotor has a 16' system that is capable of pumping 4 gpm in 15-20 mph winds. I am not sure of what the total costs of their windmill/pump/ tower combination would set you back though.


  I just see that AeroVironment as pricey, and it looks like it's geared towards PV applications, also.

« Last Edit: March 13, 2008, 05:03:48 AM by zeusmorg »

oztules

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Re: Options for Wind-Electric Water Pumping
« Reply #13 on: March 13, 2008, 05:42:18 AM »
You have the proper solution Peter


Here is the required device. http://www.turbex.co.za/Documents/Turn_Pump.htm


240m lift no problem.

even from their smallest unit in 20k breeze they can push 1000 l/hr over a distance of 15km through 40mm pipe.


Very impressive. At least the locals will be able to keep this going. I think that the electrical solution smacks of idiocy. Unless you can find Afghan electrical engineers to look after it out in the paddock, 2 years from now..... will not be working.


The Turbex also has power generating facilities.... up to 20kw. It is designed for African remote use...

http://www.turbex.co.za/Documents/WindGenerator.html

and can be set up for both power and water.... interesting.


It runs very slow, and seems to require limited maintenance.


.......oztules

« Last Edit: March 13, 2008, 05:42:18 AM by oztules »
Flinders Island Australia

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #14 on: March 13, 2008, 05:49:19 AM »
Thanks for the comment on the AeroVironment. I have no idea how well it would work with wind rather than PV. I think they will not guarantee it if I do use it with wind, though.


I should have mentioned the volume:



  1. homes @ 7 people/home = 3150 people
  2. liters/day min water/person * 3150 people = 63,000 liters/day or 63 m^3/day


That's on the low end, and the system should be scalable.


This site is not currently without water. There are number of hand water pumps at shallower depths, though some are too difficult to use.

« Last Edit: March 13, 2008, 05:49:19 AM by cslarson »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #15 on: March 13, 2008, 06:23:40 AM »
The following graph is found on the Turbex website. These figures are for a site with an average 5.5m/s windspeed. According to this, their largest unit, with a 7.8m wheel will pump approximately 1200 L/h at 170m, or 28.8 m^3/day (less than half what is needed). The system would cost US$19,000 (head) + $9,000  (smallest tower for that head) = US$28,000.


The question of sustainability is an important one. The wind-electric turbines would be produced in Afghanistan, and the installations would be by Afghans, and backed by private enterprise. I think the wind-electric systems are more versatile, and also seem to be cheaper.


(Let me know if I've gotten something wrong with my numbers.)




« Last Edit: March 13, 2008, 06:23:40 AM by cslarson »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #16 on: March 13, 2008, 06:42:06 AM »
some potentially relevant photos. my friend is blurred out. this work has all been initiated by the ngo who is proposing the diesel generator scheme for the pump.










« Last Edit: March 13, 2008, 06:42:06 AM by cslarson »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #17 on: March 13, 2008, 07:12:45 AM »
DC Pumps:


Lorentz has a solar controller unit called the PS1200. They have a few pumps that might operate at the 150-170m depth that would pump between 0.5-0.8m^3/hour (the HR-03H and HR-04H models). The combination controller + dc pump looks to be about $1500. An AC power pack is available (though a bit pricey at $600 i think) so that pumps could be powered via a generator.


Two of the pictures in the above posting show the well. The pipe that is currently there is pretty big (~12inches?). The drop pipe for the Lorentz pumps is 1 1/4". Could a few of these be put down that large pipe? At slightly staggered depths?


If that would work it might be quite cheap @~$3500/turbine+controller+pump+accessories. The additional benefit is that the same controller/pump system would be used on smaller wells. No batteries!


Flux, I think this is along the lines of what you were suggesting?

« Last Edit: March 13, 2008, 07:12:45 AM by cslarson »

zeusmorg

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Re: Options for Wind-Electric Water Pumping
« Reply #18 on: March 13, 2008, 08:41:01 AM »
  I've never seen multiple pumps put down one bore, but i can think of a couple of possible problems, which may be overcome easily.


  When a pump kicks on, it does have a tendency to twist, and could possibly tangle up on another pump/line so there would have to be some method of separation?


  I do like the idea of several separate setups, vs one huge one since it means simpler controls & electronics and if one does go out, you have the capacity of the others to hold you through.

« Last Edit: March 13, 2008, 08:41:01 AM by zeusmorg »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #19 on: March 13, 2008, 09:07:02 AM »
Great, thanks for the response. What other problems might we encounter?
« Last Edit: March 13, 2008, 09:07:02 AM by cslarson »

oztules

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Re: Options for Wind-Electric Water Pumping
« Reply #20 on: March 13, 2008, 09:24:49 AM »
If you check the releigh wind distribution, you will probably find 2 units would do the job. You will require at least this much blade exposed to the wind to do it electrically anyway... at least this is direct drive with no other losses.


I'm not selling/wouldn't know about Turbex, but you can bet they are slow and last just like the old pumpers did... 50 years on they still are running. I'm finally doing some maintenance on some 60 year old ones. They still pump every day in a marine environment..... even the fencing wire doesn't last this long.


Electrical systems are bad enough in remote places, electronic systems are to be avoided if possible.


If you could get reliable water for 3000 people for $70,000, and have no ongoing upkeep or problems or down time.... then this is an extremely cheap system...

If you have a messy system which is not instantly understood by a person sent to fix it, it won't be fixed. You may start with the right personal in place to get it to run, but people move, or die, and if no replacement is there to tend the network of small windmills and electrical and electronic gadgetry, then there is no future in it.


And yes I am currently designing a 3ph motor drive system, so am in favour of your idea from an experimental perspective, but not in the lives of simple folk who just want reliable drinking water, and don't much care how they get it.


The wind power over a year (if you can store it succesfully) is well in excess of the average wind speed x windmill output figures. The cube law for airspeed/power shows that the power from above average winds is much much larger than the power in the below average wind speeds.... which all go to makeup the average.


So the pumping figures you show are below what we should expect for that average site..... if you can use it all as it comes in.

So if you get a decent blow that pumps 3 days worth of water in a day, the big pumper will do it. How will the network of smaller ones with fixed upper boundaries do.

eg. If we pump a days water at 5ms on an "average day", and your system is designed around this.. next day when we get 10m/s, the pumper might pump 8 days of water, because it can utilise the 8 times the power in the twice average speed.

What will the electrical system do.

If in the next month we get a day of three times average speed 15m/s we can expect to pump 3x3x3=27 days of water. What will the electrical system be doing with this unusual extra wind?... and there will probably be a few days of it with a weather pattern of this type. In the real world, the figures would no be so nicely extrapolated, but you get the idea.


Any system that requires dump loads and furling to protect the alternators, will not take advantage of this fact. Strong winds will be dumping or the mill will be furling. The water pumper just pumps more water, (will furl in extremes), but not just strong winds that would furl a small wind generator. In other words the pumper can more likely take advantage of the strong winds where the real power is, general rule is that the small electrical mills will all be in furl and/or dumping if the batt bank is small.


I only use smaller(5'-8') wind pumpers, so this may all be nonsense in the bigger machines, but I'm sure a call to Turbex will get some info, and I notice they publish customer names to contact.... might be a worthwile exercise.


But thats how it works for us.


..........oztules

« Last Edit: March 13, 2008, 09:24:49 AM by oztules »
Flinders Island Australia

feral air

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Re: Options for Wind-Electric Water Pumping
« Reply #21 on: March 13, 2008, 09:43:37 AM »
An airlift pump is a pretty good idea. Maybe this could be tested/used on the wells that are currently being hand-pumped.


It looks like the deep well pipe is too large for airlift - I could be wrong though. If it would work with the large pipe I have a feeling you would need high power blowers (a dozen leaf blowers?) and then back-pressure on the blowers could be a problem.


It's probably worth researching a bit, anyway. take it easy

« Last Edit: March 13, 2008, 09:43:37 AM by feral air »

Electron Skipper

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Re: Options for Wind-Electric Water Pumping
« Reply #22 on: March 13, 2008, 10:23:30 AM »
I like the idea of the staggered pumps.  You would have to bracket them together as one assembly to limit the torsionsal effects already mentioned.


One other option for the pumps to simplify things once you have achieved about the 65 Meter depth is a low voltage well pump available from Shurflo.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200332019_200332019  Is just one vendor, posted because the specs are there.


The aspect of running well pumps from an efficient inverter system is a specific aspect of a book I have been working on that has taken the most time.  the block diagram is easy and simple, but finding a simple low frequency oscilator with a sine wave output that has excellent stabillity....  With the discontinuation of availability of the "MAX038" chip, the solution is not so easy, and as time has been at a premium for me these days....  


BUT the matter is not insurmountable, but would be very useful right now if I had finished this portion of my book.  A solution may be ultimately as simple as/ or to be found in the schematic of one of the newer energy efficient frontload washing machines for concept- they use a 3 phase motor with PWM and a bit of variable frequency to ramp up the speed, and ramp it down.  Having scrapped out one of mine already for mechanical failure, I may take a look at those parts for a better answer.  Hysteresis losses (internal heat) are not as great when doing this with a three phase pump motor- Electrolux is using just PWM square wave as the drive method for their washing machines. I may be giving away part of my book here, but such schematics can be gleaned and adapted from simple motor control devices covered in Industrial electronics books.  


From the sounds of what is available over in Afghanistan from this thread so far, they may have to build the circuitry they need, which is why I raise this.


At the simplest description I can think of- consider an AM transmitter where the "audio portion" is power MOSFETs firing, and the exciter is a 50Hz or 60 Hz sine wave.  Variable from "0" to the rated frequency for ramping up and ramping down.  Yes, this the dreaded "modified Sine wave" but remember your motor is immersed in water- constantly drawing away heat.  You Class "D" audio amplifiers use this method for creating major amounts of audio power with less than logical heat sinking.  The real killer of well pumps is the "on/off" nature of their service.

« Last Edit: March 13, 2008, 10:23:30 AM by Electron Skipper »

Electron Skipper

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Re: Options for Wind-Electric Water Pumping
« Reply #23 on: March 13, 2008, 10:38:25 AM »
I forgot to add- if output voltage regulation feed to the pump motor is deemed important- you have no real choice but to rely on inverters.  Most motors however  are quite forgiving in this aspect within reason.  If your voltage is low, you have to compensate with more current.  This may be repeating something you know, but others reading this may not.


Within the inverter, you can regulate your low voltage " frequency signal" prior to waveshaping with 2 simple linear voltage regulators set up as is shown in the National Semiconductor Application sheet for the LM117/317 regulator.  This allows you a means to trim your AC current potentials as needed.

« Last Edit: March 13, 2008, 10:38:25 AM by Electron Skipper »

jacobs

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Re: Options for Wind-Electric Water Pumping
« Reply #24 on: March 13, 2008, 06:24:14 PM »
You might want to consider an Iron Man windmill that's made in China. The owner of the company is an American engineer and the windmills are an exact copy of the old tried and true Ameriean made Chicago Aremotor. The website is http://www.ironmanwindmill.com/
« Last Edit: March 13, 2008, 06:24:14 PM by jacobs »

jacobs

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Re: Options for Wind-Electric Water Pumping
« Reply #25 on: March 13, 2008, 06:30:29 PM »
Bowjon made airlift water pumping systems a few years back but went out of business due to numerous failures of their compressors. They were not dependable but did work well for awhile. I would think twice before considering this type of system.
« Last Edit: March 13, 2008, 06:30:29 PM by jacobs »

jacobs

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Re: Options for Wind-Electric Water Pumping
« Reply #26 on: March 13, 2008, 06:34:16 PM »
Sorry...ment to say American made Chicago Aermotor.
« Last Edit: March 13, 2008, 06:34:16 PM by jacobs »

Drives

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Re: Options for Wind-Electric Water Pumping
« Reply #27 on: March 13, 2008, 08:15:43 PM »
A few comments.


Flux is clearly correct on all accounts.  


I would not even consider a centrifugal pump for 170 meters of head.  Positive displacement only makes sense.


Also correct is the problem of directly connecting a 4 meter wind turbine to a 5-7.5HP pump.  (Side question, did you check to be sure 5.5KW is big enough?)

My limited understanding of wind turbines shows that 4 meters is too small for that size pump.  Unless you can increase wind turbine size, I agree with Flux that connecting 2+ turbines to syncronize AC outputs is doubtful.


"Feeding dc to a vfd seems simple in theory but you would need a fair bit of circuitry to hold the volts within limits. You will also need a supply for the drive control circuits."


This is spot on.  The circuitry to regulate the DC Bus voltage is tricky but doable.  The key would be its speed of response.


"It is likely that you will be forced to use a standard unit and modify it. Otherwise starting from scratch I think a vfd could be produced to accept a dc rail that rises with the motor speed just as the motor will accept raw ac as long as it varies in voltage and frequency in the correct ratio ( which it does in this case)."


15 years ago we had VFD's that had a DC Bus voltage which varied in amplitude and we regulated the output frequency to the motor based off this voltage....sadly I filled dumpsters with many of them.  I haven't seen one in 8 years.  They were called PAM (Pulse Amplitude Modulated) drives verses todays PWM's.


My opinion, but if you want to stay simple, and electric, then FLUX's suggestion is the perfect solution "Seriously worth thinking about using more smaller dc pumps"


You could rectify the output of all your wind turbines, connect them in parallel, and feed it down to a Positive Displacement DC well pump(s).  No inverters, no batteries...simple solution.

Remember the wind turbine works off the affinity laws just like the pump does...sounds like a perfect match.


I also agree with Oztules & Dinges posts, water pumper mills are proven, and easier to maintain by most people.


I think the DC pump system would also be easy to maintain.


Interesting discussion.

« Last Edit: March 13, 2008, 08:15:43 PM by Drives »

cslarson

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Re: Options for Wind-Electric Water Pumping
« Reply #28 on: March 14, 2008, 08:24:31 AM »
I just wanted to say thanks to all those who commented on this posting. The diverse ideas that have been presented have fascinated me. Additionally, it looks like further exploration is warranted for a solution I had not previously considered, that of using multiple dc pumps fitted down the larger bore hole.


I'll keep you all posted.

« Last Edit: March 14, 2008, 08:24:31 AM by cslarson »

thefinis

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Re: Options for Wind-Electric Water Pumping
« Reply #29 on: March 15, 2008, 08:30:40 AM »
Having been around windmills water pumpers all my life I think that it is the solution that is needed here. Technology is great if you have the support available to back it up. While I think that they could take care of old style water pumper windmills it is rather doubtful that they will have the expertise or the supplies or the money to keep the proposed diesel or electric wind system going. A 16 foot diameter windmill with a 4 inch cylinder would pump quite a bit of water even at that depth but a better solution to start with might be to setup smaller windmills with tanks on the shallower wells closer to town if the water quality is suitable. The diesel or wind electric system is probably a step or two down the road after the town has been setup and established for a while.


If electricity is available in town they make a submersible that attaches below the check valve in the pumping cylinder that could be turned on in times of no wind. This might even work as a combined system for the big well above town. A solar or wind system even the diesel system as a backup for when the wind isn't blowing.


check out this website for aremotor windmills and various pumping solutions.


http://www.aermotorwindmills.com/index.htm


I am not promoting or recommending this company and suggest that it be used as a starting point for what is available @ what cost and then find the supplier closest with the best backup to your location.


It would be easier to calculate what is needed if resources, well data and water needs were available.


Good luck

Finis

« Last Edit: March 15, 2008, 08:30:40 AM by thefinis »

finnsawyer

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Re: Options for Wind-Electric Water Pumping
« Reply #30 on: March 15, 2008, 09:19:05 AM »
Makes you wonder about these aid programs.  If I had that 12 inch pipe with a good water source sticking out of the field behind my house, I could put in a housing development and make big bucks.  Where it is, it may be overkill.  Like you say, why couldn't they have tapped into the existing wells?
« Last Edit: March 15, 2008, 09:19:05 AM by finnsawyer »

feral air

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Re: Options for Wind-Electric Water Pumping
« Reply #31 on: March 15, 2008, 03:05:47 PM »
If 600 people donated $20 each, the fuel cost could be covered for a year. If I could give via paypal, I've got $20 on it - an honest pledge, scout's honor.


Maybe fieldlines could get in on the act...set up a donation box on the front page so giving is easy, maybe as part of a new poll...


Some of the other sites I frequent have donation boxes for various things, from "we need a new server" to cancer research. Some sites run multiple drives so if you don't feel like giving to one cause, maybe you'll give to another.


It may not be the best solution but it might be able to lift the burden for another year. take it easy

« Last Edit: March 15, 2008, 03:05:47 PM by feral air »

TomW

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Re: Options for Wind-Electric Water Pumping
« Reply #32 on: March 15, 2008, 04:45:35 PM »
feral;


It is nice that you want to help, but.


What does this do about getting them self sufficient and pumping water with wind?


I do not think tossing short term "fix" cash at these type problems will be much long term help.


I pretty much think they are making a simple thing overly complex by going wind to electricity then to pumping power.


Water pumper mills have a long and proven history in real world use with little to no maintenance. Some oiling and a change of leathers is about all they need and can pump water from extreme depths very reliably for decades in extreme conditions.


That same 12 grand would go a long ways towards a setup to do the job.


Just seems silly to make a restrictive set of requirements rather than just starting with "We need to pump water from X depth and would like to use wind as a driving force".


Anyway, just don't think this question is a tough one at all if you remove the prerequisite of wind>>electric>>pumping power.


However, Local conditions vary so much it is difficult to know what will truly be "best" over an extended period.


TomW

« Last Edit: March 15, 2008, 04:45:35 PM by TomW »