# Pump Energy Cost Calculator

> Pump Energy Cost: Hydraulic kW = ρ × g × Q × H ÷ 1,000. Methodology stated, your own inputs only.

Page: https://freecalculator.tech/tools/pump-energy-cost-calculator
Last reviewed: 2026-10-20

## Formula

Hydraulic kW = ρ × g × Q × H ÷ 1,000. Input kW = hydraulic ÷ (pump eff × motor eff). Cost = input × hours × price.

- Methodology: hydraulic power relationship from the U.S. DOE pumping system sourcebook; g = 9.80665 m/s².
- Pump efficiency comes from the pump curve at your duty point.
- Links: Pump Power and Pump Efficiency pages cover the power figures alone.
- Hydraulic kW = ρ × g × Q × H ÷ 1,000. Input kW = hydraulic ÷ (pump eff × motor eff). Cost = input × hours × price.
- Inputs used: Currency (symbol only, never converted), Flow rate, Total head, Fluid density (water ≈ 998 at 20 °C — enter yours), Pump efficiency (pump curve), Motor efficiency, Running hours, Your energy price per kWh (from your bill or a saved rate).

## Inputs

- Currency (symbol only, never converted)
- Flow rate
- Total head
- Fluid density (water ≈ 998 at 20 °C — enter yours)
- Pump efficiency (pump curve)
- Motor efficiency
- Running hours
- Your energy price per kWh (from your bill or a saved rate)

## Worked example: A cooling water pump

0.05 m³/s, 30 m head, water 1,000 kg/m³, 75% pump, 90% motor, 3,000 h at $0.10.
1. 1,000 × 9.80665 × 0.05 × 30 ÷ 1,000 = 14.71 kW.
2. 14.71 ÷ 0.75 ÷ 0.90 = 21.79 kW.
3. 21.79 × 3,000 × 0.10 = $6,537.77.

## Common questions

### Why isn't an electricity or fuel price filled in?

Prices differ by country, supplier, tariff and time of use, so there is no universal figure. Enter the rate from your bill or contract, or pick a dated saved rate if one is listed on the page.

### What is total head?

The static lift plus friction and pressure losses in metres of fluid, from your system curve. Check the formula, example, and limitations on this page before using the result for a real energy decision.

### Why enter density?

Fluids and temperatures differ; water is close to 998 kg/m³ at 20 °C but brines and oils are not. Check the formula, example, and limitations on this page before using the result for a real energy decision.

### How do I use the Pump Energy Cost Calculator?

Enter the required values for Currency (symbol only, never converted), Flow rate, Total head, Fluid density (water ≈ 998 at 20 °C — enter yours), Pump efficiency (pump curve), and the other fields shown. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.

### What formula does the Pump Energy Cost Calculator use?

Hydraulic kW = ρ × g × Q × H ÷ 1,000. Input kW = hydraulic ÷ (pump eff × motor eff). Cost = input × hours × price. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.

### Can the Pump Energy Cost Calculator be used for exact decisions?

Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.

## Limitations and assumptions

- Single steady duty point.
- Drive losses not included.
- Results are estimates built only from the figures you enter. No electricity, fuel or gas price, equipment efficiency or benchmark is built in — tariffs vary by supplier, region and time, and equipment data must come from the manufacturer. Designs and installations must be checked by a qualified professional.
- The result depends on the values you enter for this pump energy cost calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.

## Sources

- U.S. Department of Energy — https://www.energy.gov/eere/amo/articles/improving-pumping-system-performance-sourcebook-industry-second-edition

## Cite this page

- APA: Free Calculator. (2026, October 20). Pump Energy Cost Calculator. https://freecalculator.tech/tools/pump-energy-cost-calculator
- MLA: "Pump Energy Cost Calculator." Free Calculator, 20 Oct. 2026, https://freecalculator.tech/tools/pump-energy-cost-calculator.
- Link: Pump Energy Cost Calculator — Free Calculator, https://freecalculator.tech/tools/pump-energy-cost-calculator