Choosing A Bore Pump
What Size Bore Pump Do I Need?
At Australian Bore Pumps, we are experts at designing and installing bore pump systems for a wide range of different applications. From a small outback farms to larger agricultural industry applications, we can help design a system to meet your application and bore size
When choosing a solar pump, you need to consider two important factors.
1/ How much water do you want/ what is the size of your bore
2/ What head pressure is required/ how deep is your bore
1/ Flow Rate
Considering the first point – how much water do you need, the usual answer is “As much as I can get”
“Whiskey is for drinking and water is for fighting over”
In the case of a solar bore pump, you may be limited by the bores ability to supply or replenish itself.
When installing a reasonable size solar pump system on a new bore, we recommend that you test the bore first.
Drillers measurements are usually good estimates over a short period of time of testing.
A single- phase submersible running on a generator for a few days will put you in a better position to make a valued decision on what size pump is required, quality of the water and volume available
All our AC pump systems have variable pump speed control and dry run protection.
Another point to consider is the sun does not shine everyday – but stock do drink every day. All our systems accept AC input from a generator or mains / grid. Storage tanks are a good idea – but burst pipes require empty tanks to be filled quickly or overnight. Smaller systems up to 1 HP can be run 24 Hours using batteries (larger systems if you want to spend the money) – this will allow the pump to pump 24 hours a day and in the case of bores a little over a longer period yields the best results. The only issue with this is batteries are not cheap – well good ones anyway.
2/ Head Pressure
When pumping from a bore, the head pressure is determined by the ‘standing water level’. Noting this level can fall when the bore is being pumped (this is why a test pump is a good idea).
When transferring water or irrigating is the intention, the static head and the dynamic head should be considered.
Basically, the volume of water, the diameter of the pipe and the distance to be pumped are the key factors.
We have installed solar pumps which have transferred water a distance of 42KM – with a daily output in excess of 60,000 litres per day, servicing 14 watering points / tanks – over this distance.
Once the volume of water and the required head pressure is known, we can determine the size and type of pump required. Our most common submersible pump for most sheep and cattle stations is a 4” – 25 stage 3HP pump, for water transfer a 16 stage 2HP vertical multi staged pump is very popular. Both these have 240V AC single phase input – back up.
When the pump size has been determined the solar system can be designed.
As a rough rule of thumb – a fixed solar array system, you should install twice the KW (HP) of the pump motor. For example, a 1 KW pump motor requires 2 KW of solar power, for a good result.
With a tracker the requirement is lower, 1.5 times motor power works well. Our standard trackers are designed to suit 2HP, 3HP, 4HP and 5.5HP pump motors – this we find covers more than 90% of our customers requirements. We have powered pump motors exceeding 185KW (250HP) with solar.
On our larger AC system’s, we do not use or recommend cheaper solar panels for solar pump applications. You get what you pay for with the cheaper Chinese imported solar panels – we have tested them many times.
I hope the above helps you in selecting the right solar pump system for you. I have not tried to complicate this advice, and given you some food for thought in making the right decision and selection of a Solar Pump system.
If you would like more help with choosing a submersible pump, please use the contact from below or try out our helpful questionnaire on our shop page here
BSc. Mech. Engineer