A solar pump inverter fits drip irrigation well, because drip needs steady low flow at a steady pressure, and a solar pump inverter varies pump speed to match the sun. Size it from the drip system’s flow and pressure duty point, keep the pump inside its efficient range, and use a tank to cover cloudy hours.
What
Drip irrigation feeds water slowly through emitters at low pressure, over long hours, instead of flooding a field in a short burst. That duty suits solar pumping: the pump runs for many daylight hours at part speed, and the inverter follows the sun instead of cycling on and off.
Why
Flood irrigation wastes water and needs short bursts of high flow; drip uses less water and runs longer, which is exactly the shape of a solar day. A pump that starts and stops all day wears faster than one that runs steadily at part speed under inverter control.
When
Size for the peak-season daily water need, not the average week, because the dry season is when both the crop and the pump work hardest. Check the design before planting, and recheck the emitters each season, because clogged emitters change the duty point the inverter was sized for.
Where
Vineyards, vegetable plots, orchards and greenhouses all use drip, and the same logic fits any low-flow, long-hours duty. The agriculture irrigation article sets out the wider solar pumping picture, and the daily-output article shows how to turn hours of sun into litres per day.
How
- Work out the daily water need in litres, then divide by the sun hours to get the flow the pump must deliver.
- Find the pressure the drip lines need at the emitters, plus the lift from the source: together they are the pump duty point.
- Size the inverter from that duty point using the sizing article’s method, and keep the pump near its efficient range rather than far below it.
- Check the panel string sits inside the MPPT window, using the MPPT window article’s method, so the pump starts early and runs steadily.
- Add a tank buffer so cloudy hours are covered by stored water, sized from daily volume as the daily-output article sets out.
- Fit a filter before the emitters and a dry-run protection on the source, and check both at every seasonal maintenance visit.
Drip duty, what it asks of the pump
| Drip feature | Pump requirement |
|---|---|
| Low flow, long hours | Steady part-speed running, not start-stop cycling |
| Steady emitter pressure | A pump that holds pressure as the sun varies |
| Clogged emitters over a season | A duty point that is rechecked, not set once and forgotten |
| Cloudy hours | A tank buffer, or a hybrid path for night pumping |
Sizing inputs to send with an inquiry
| Input | Why it is needed |
|---|---|
| Daily water need in litres | Sets the flow the pump must deliver |
| Emitter pressure plus lift | Sets the pump duty point |
| Source type and depth | Sets the pump type and the dry-run protection |
| Sun hours in the dry season | Sets the array size and the tank buffer |
Frequently Asked Questions
Can a solar pump run drip lines directly?
Yes, when the pump duty point matches the drip pressure and flow, and the inverter varies speed with the sun.
Do I need a battery for drip irrigation?
Usually not: a tank stores water for cloudy hours more cheaply than a battery stores electricity, as the night-pumping article sets out.
What if the emitters clog?
Flow falls and pressure rises, which changes the duty point; clean or replace emitters and recheck the inverter’s running point.
Will a bigger pump water the crop faster?
No: drip lines take only their design flow, so a bigger pump raises pressure, wastes power, and risks blowing fittings, not faster watering.
How do I keep the pressure steady on a cloudy day?
A tank buffer holds the supply, and the inverter’s speed control follows the available sun; the cloudy-day article sets out the same logic.
To get a drip sizing check for the QB100 PV Solar Pump Inverter, send the daily water need, emitter pressure, lift and source details.