How to choose the pump, inverter and solar panels for PV irrigation system?

It is depended on which kind of inverter you puchase.

Take INVT GD100-PV series solar pump inverter as an example.

Type 1: Pump(3AC380V, work 6 hours per day)

1. Check pump rated specification(7.5kW/380V/18A);

2. Inverter current = pump current*1.4(18A*1.4A=25.2A);

3. Check inverter rated output current(GD100-PV catalogue Page7 show GD100-011G-4-PV current is 25A);

4. Solar panel power = inverter power*1.4 (11kW*1.4=15.4kW);

5. Solar panel quantity = total solar panel power ÷ solar panel unit power(15.4kW÷300W≈51pcs);

6. Make solar panel Open-circuit Voltage(Voc 45V) less than 800V, make Max-power Voltage (Vmp 37V) near 550V or more than 550V.(51pcs = 17*3, Voc 45V*17=765＜800V, Vmp 37V*17=629＞550V);

Type 2：Pump(1AC220V, work 6 hours per day)

1. Check pump rated specification(0.75kW/220V/7A);

2 . current = pump current* 1.4(7A*1.4A=9.8A);

3 . Check inverter rated output current(GD100-PV catalogue Page7 show GD100-1R5G-SS2-PV current is 10.2A);

4 . Solar panel power = inverter power * 1.4 (1.5kW*1.4=2.1kW);

5 . Solar panel quantity = total solar panel power ÷ solar panel unit power(2.1kW÷300W≈7pcs);

6 . With boost module, make solar panel work in series and total Vmp more than 80V(Vmp 37V*7=259＞80V);

7 . Without boost module we have to make total Vmp around 330V. Then we need 11pcs solar panel(330V÷Vmp 37V = 9pcs);

Conclusion

1. Sometimes customers will complain solar panel is too many. But we should tell them, this is for 6 hours per day and working without fault.

2. If we don't know pump current, we will make inverter power one level higher than pump power. We calculate current because some pump have different current.

water pump inverter 15kw