water pump & equipment for 30M deep borehole, well

[notrub]

This is about drilling a borehole / well on the 30 rai of land that the family owns outside our village.  There is no electricity now.  I looked at a solar solution and the panels would be like having 3 sheets of plywood erected and protected from the elements and theft.  Plus the cost.

 

The water is not required except when there is no rain.  That will be perhaps a couple of times a year.  I have decided to go for a 220 volt AC pump down the hole and a generator which could be taken to the fields 5km away and start it and pump all day and then take it home at night.  They also have a pond already but it is not near the road and the well will not be near to it.

 

I have been told that a 2 or 3 KW generator is not big enough as there is a surge when the pump comes on.  The generator has to be powerful enough for the job but preferably small enough to be loaded onto the 3 wheeler, not a truck.  Or, if it is a big generator a pump house would have to be built to protect the generator from theft.  I am looking at a down the hole pump and it does not matter about not switching off on its own except when the water runs out, perhaps.  Old Dad can sit in the field for as long as it takes.

 

I was also thinking of a series of pipes to irrigate different fields that are separated in the normal way with earth banks/walkways.

 

There is a huge variety of pumps and generators so I am looking for some guidance on pumps - size and brands names. Same for generators, power and brands please.  I am on a budget so if I could get away with 8,000 for a pump and 10 to 15,000 for a generator that would be great.  The water pump can be slow in volume and low pressure at the surface.   The drilling is 9,500 for 35 meters done by the local guy who does all the wells in the area and is a good person. 

 

Thanks in advance for any help.

[farmerjo]

The diameter of the borehole will probably determine pump size.

Best to asked the contractor as he will be able to give you a flowrate of the bore's capability.

Then you could purchase a pump,since he will probably test for you,you could use his generator for initial test and check how many kw's it pulls on start up to decide the required size is.

If i did mine again i would use 10mm wire cable to suspend the pump in the hole and ldpe poly pipe up the bore rather than pvc for ease if have to remove pump.

[John P Ryke]

what is the height that the pump has to suction lift........what I mean is the distance from the ground level to the water below

[John P Ryke]

if it less than 25 feet roughly 8 metres you may be able to get away with a centrifugal firefighter linked to a 5hp petrol motor.....this is a much cheaper option that talking about submersibles.....

one of the advantages of a petrol driven centrifugal is they are very mobile......you simply disconnect the suction pipe and discharge pipe and put it in your car to store in a safe place.....if you interested in this the Honda has always been the no1 pump in this category. they are not a low output pump but at the pump with no pipe friction deliver nearly 450 litres a minute......these pumps have a max discharge lift of around 100 feet but this is not what the have been designed for.......

 

in other words you cannot get away with using much less than 2 inch poly if you have a bit of a distance to where you want the water. 

a problem you might encounter is the amount of water that these pumps discharge .......use 200 litres a minute as an example has to be able to have this capacity in the bore.....otherwise you will simply be running a dry pump.......a few minutes is ok but doesn't take long to do big damage to the pump....   

 

hope this helps

[notrub]

Thanks for your comments.  Events have moved on and I had a well drilled 35 M deep with the top 8 M sleeved with 150 mm PVC pipe.  I went for an AC 1 1/2 HP pump and a 5 KW generator.  Works a treat.  Now, however, after 3 /4 days I am on my way down to buy some solar panels and a DC pump.  I have spent about 3000 baht in the last 36 or 48 hours on fuel plus going to the fields 2x + per day as the pump runs for 11 hours on a 25 L tank of gas.    AND only one of 12 fields is damp all over.  Damp being a key word.  I can use the pump at home and the pipe will be used for the new system so I am out 'only' 20,000 baht for a 5 KW generator and gasoline costs.  It will come in handy one day, I suppose.

 

BTW.  The drilling contractor used 1 1/2'' pipe and glued threaded connectors to each and teflon taped them all.  As the pump went down he screwed the pipes together.  Far better solution than trying to glue pipes whilst lowering the pump.  (done that, hard to do correctly) Not much extra cost for a much better job.  Also, now changing the pump will be much easier.

[farmerjo]

On 6/25/2019 at 8:14 AM, notrub said:

Thanks for your comments.  Events have moved on and I had a well drilled 35 M deep with the top 8 M sleeved with 150 mm PVC pipe.  I went for an AC 1 1/2 HP pump and a 5 KW generator.  Works a treat.  Now, however, after 3 /4 days I am on my way down to buy some solar panels and a DC pump.  I have spent about 3000 baht in the last 36 or 48 hours on fuel plus going to the fields 2x + per day as the pump runs for 11 hours on a 25 L tank of gas.    AND only one of 12 fields is damp all over.  Damp being a key word.  I can use the pump at home and the pipe will be used for the new system so I am out 'only' 20,000 baht for a 5 KW generator and gasoline costs.  It will come in handy one day, I suppose.

 

BTW.  The drilling contractor used 1 1/2'' pipe and glued threaded connectors to each and teflon taped them all.  As the pump went down he screwed the pipes together.  Far better solution than trying to glue pipes whilst lowering the pump.  (done that, hard to do correctly) Not much extra cost for a much better job.  Also, now changing the pump will be much easier.

Please let us know how you got on with the solar package.

[notrub]

The solar has one big problem for me.  How can I protect it from being stolen from its remote location.

 

I will post a list of equipment and costs as soon as I can.  The short answer is that it is just great. High end panels work even on cloudy days and the pump is the best available.

 

It cost 23,000 for everything solar.  The pipe, borehole and establishing the well head was another 11 or 12,000.  Also 100 M of flat 1 1/2 hose roll 1,700 baht.   From now on, water is free.

 

Will post name and contact details of the supplier who is knowledgeable and honest. 

 

Burton

 

 

[farmerjo]