Pump hydraulic power
A compact explanation of hydraulic power, flow conversion and efficiency for preliminary water-pump sizing.
ENGINEERING PRINCIPLE
Hydraulic power is the rate at which a pump increases fluid potential energy; shaft input rises as efficiency falls.
Pinput = ρgQH/ηVariables and units
- ρ in kg/m³
- g in m/s²
- Q in m³/s
- H in m
- η as a decimal
Worked example
For water at Q = 0.015 m³/s, H = 30 m and η = 0.70, input power is approximately 6.31 kW.
Conditions and reference
Formula and displayed units independently checked for the stated conditions. This is not a code-compliance design method.
Source: Hydraulic-power relation derived from conservation of energy; use manufacturer curves for selection.