Note the motor’s depth in feet, its size and its daily running hours. A quote should show all three.
Measurements for quotes
- Note your water source: borewell, open well, pond or canal.
- Measure the dry-season water level while pumping at the flow you want.
- Or measure the still water depth and add the drop (count the drop once).
- Note how much water the source can give steadily.
- Measure the height from the water to the highest outlet or tank water level.
- Note the suction and delivery pipes’ length, inside width, material and fittings.
- Note the pressure you need at the outlet for drip or sprinklers.
- Note the water you need on your busiest day, in litres a day.
- Note the hours you can pump.
Total head
Total head is the sum of three parts:
- the lift from the pumping water level to the outlet;
- the loss in pipes and fittings at the flow you want;
- the pressure you need at the outlet.
Panels by motor size
Each figure is a count of 550 W panels for a borewell motor.
| Example | 4 hours a day | 6 hours a day | 8 hours a day |
|---|---|---|---|
| 1 HP | 2 | 3 | 4 |
| 2 HP | 4 | 6 | 8 |
| 3 HP | 6 | 9 | 12 |
| 5 HP | 10 | 15 | 20 |
| 7.5 HP | 15 | 22 | 29 |
These examples assume no drawdown or pipe loss.
These figures use PVGIS data for Hyderabad’s weakest month.
What a quote should show
- The installer should state the flow and total head they assumed.
- The quote should include the pump’s performance curve and the pump type.
Farm subsidies
PM-KUSUM is the farm solar pump scheme, separate from the home rooftop scheme.
The central subsidy is up to 30% of the cost. With the state’s share, the subsidy is up to 60%.
New sanctions are limited to projects with agreements issued by 31 Dec 2025. Work must be finished by 31 Mar 2027.
Its successor, PM-KUSUM 2.0, is at the proposal stage.
Sources and tools
- IWMI, Solar Irrigation Pump Sizing Tool, beta user manual, March 2022 (free Excel tool).
- MNRE, updated specification for solar water pumping systems (listed 21 Apr 2023).
Source: MNRE, official PM-KUSUM portal ↗