Borehole pump...

[Contadino]

Hello,

I live in southern Italy, off-grid as far as water is concerned.  We have a large rainwater catchment area routing into an 80,000 ltr underground cistern.  As we grow more produce on our land, our demand for water throughout summer increases, and I've been looking into two options for meeting this demand:

Option 1: A bore hole, which we would use to top up our cistern when required.  In our region, noone divines for water - the guys just bore down 250 to 300m and you have water.  Simple...?  Not quite.  They then sink a 3kw pump down the pipe, but our electricity supply is 1.5kw and we don't really want to upgrade it (cost, time & hassle make it pretty much prohibitive.)  A shame really, as we have wind and sun in abundance.  The pump pumps approx 250 ltr/hour, so it's not fast either.  Estimated cost for installation: EUR 5,000

Option 2: Another cistern.  We have sufficient catchment area for another 100,000 ltrs of capacity, which would keep us going for another couple of months (and then some) if need be.  There are potentially two catches: Firstly, we would ultimately still be reliant on rainfall, and secondly the new cistern would be 100m away from the house and 200m away from the vegetable plot and would need pumping.  Estimated cost of installation EUR 6,000 without the pump.

So my questions are:

1. My research for a 12v borehole pump hasn't come close to a 300m lift (but I didn't really expect it to.)  I think powering it from home produced AC (solar or wind) would knock it out of our price range.  Anyone gonna tell me otherwise and make my day?

2. Mechanical wind-powered pumps are not something I've looking into.  Should I, or would the bore-hole head be too high?

3. To pump from the new cistern could possibly be achieved with a ram.  Has anyone got any real world experience of these pumps, including the real cost to get them running?

Many thanks,

Jeremy.

[Ivan]

Navitron has a solar-powered well-pump, but it won't do 300metres. I will check with the supplier to find out if there is a 300m option.

Ivan
Navitron

[billi]

hi

my supplier connects solar pumps in series or in paralell to muliply the flowrate or the head....

do not know if that can be done in a tiny borehole....

but 300 m is deep , so i would think to pump it with solar and or wind will cost a lot

its hard to estimate how much water you can take out of your bore hole and how fast it refills ,
but i would think  the borehole will fill up to a  shallow level feeded by the water "venes" in the hole and their pressure
thats just estimating , our neighbours bore hole is allways overflowing , but thats because of the hills arround....
so perhaps a shallower pump with little constant flow could do as well...

most drill companies like to drill deep , because more monney and to supply a storage ...... of water in the hole

here is some info   http://www.builditsolar.com/Projects/WaterPumping/waterpumping.htm

250 l an hour for a 3 kw pump sounds not good performance , perhaps a stronger pump with a generator or direct engine driven pump could work as well as the air pressure pumps you can use with a windmill

but personally i like the water storage idea more.......