System design:
Here is a water pumping system design example, for a customer from Pakistan who needed three models of pumps:
1. 12 gallons/min, 10 hours/day = 7200 gallons=27.2 M3
2. 22 gallons/min, 10 hours/day=13200 gallons=50 M3
3. 32 gallons/min, 10 hours/day=19200 gallons=73 M3
The well is within 80 feet=24.38M of the system outlet. After the water is lifted from the well, we need a tank to store the water. Assume the tank is 5 meter high, so the total lift is 30 M.
Selecting an AC pump:
Referring to our pump data sheet, we can find:
1. 27.2 M3 at 30M, it is 5.44 M3/h for 5 hours. R95-VC-09 is selected, with 1”1/2 outlet, 4” max diameter of the pump.
Power is 0.75KW.
2. 50 M3, it is 10 M3/h for 5 hours. R95-DF-08 is selected.
With 2” outlet, 4” max diameter, 1.5KW.
3. 73 M3, it is 14.6 M3/h for 5 hours. R95-MA-10 is selected.
With 2” outlet, 4” max diameter, 2.2KW.
Selecting solar panels to power the pump:
1. 0.75KW pump needs 1425Wp, which is 9 pcs of 160Wp
panels in series.
2. 1.5KW pump needs 2700Wp, which is 9 pcs of 150Wp
panels in series, and two series in parallel.
3. 2.2KW pump needs 3520Wp, which is 16 pcs of 220Wp
panels in series.
Selecting the frequency variable inverter size:
1. 0.75KW pump needs a 1.5KW FV
inverter.
2. 1.5KW pump needs a 2.2KW FV
inverter.
3. 2.2KW pump needs a 3.7KW three phase inverter.
After the water is pumped out, it is recommended that the farmers
build a tank to hold some of the water. Otherwise, the water could just flow to the farms directly.
