Pump Power Calculator
Shaft power a pump needs for a given flow, head and efficiency.
Results
Power
2.919
kW
Power
2.043
kW
What this tool does
Hydraulic power is what reaches the liquid; shaft power is that divided by the pump efficiency. Real pumps sit between 55 and 85 percent depending on size and duty point.
Formula
P = ρ × g × Q × H ÷ η
Variables
| Symbol | Meaning | Unit |
|---|---|---|
q | Flow rate | m³/h |
h | Height | m |
d | Density | kg/m³ |
ef | Efficiency | % |
P | Power | kW |
PH | Power | kW |
Worked example
- Flow rate30 m³/h
- Height25 m
- Density1000 kg/m³
- Efficiency70 %
- Power2.919 kW
- Power2.043 kW
Limitations
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.