What formula does this calculator use?

The calculator uses kWh = hp × 0.74569987 × h, where hp is mechanical horsepower, 0.74569987 is the exact conversion factor (1 mechanical hp = 0.74569987 kW), and h is time in hours. Multiplying hp by the conversion factor gives kilowatts; multiplying by hours gives kilowatt-hours.

What type of horsepower is used?

This tool uses mechanical (imperial) horsepower, defined as exactly 550 foot-pounds per second or approximately 745.7 watts. Metric horsepower (PS, used in some European countries) is slightly different at 735.499 watts. For metric hp, multiply your result by 735.499/745.7 ≈ 0.9863.

What is a kilowatt-hour?

A kilowatt-hour (kWh) is a unit of energy equal to 1,000 watts consumed for one hour. It is the standard unit used by electricity utilities worldwide for billing. Converting horsepower to kWh lets you compare mechanical engine output with electrical energy costs.

How do I convert minutes to hours for the time field?

Divide minutes by 60 to get hours. For example, 90 minutes = 1.5 hours, 30 minutes = 0.5 hours, and 15 minutes = 0.25 hours.

How many kWh does a 100 hp motor use in 8 hours?

kWh = 100 × 0.74569987 × 8 = 596.56 kWh. At a typical electricity rate of $0.12/kWh, that would cost about $71.59 to run.

Can I use this for electric motors rated in horsepower?

Yes. Electric motors are often rated in horsepower on their nameplates, and this calculator converts that rating to kWh energy for any run time. Note that the result is shaft output energy; input electrical energy will be slightly higher depending on the motor efficiency (typically 90–95%).

Horsepower to Kilowatt Hours Calculator

Name: Horsepower to Kilowatt Hours Calculator
Availability: InStock
Author: Nham Vu

Enter power in horsepower and duration in hours to calculate the equivalent energy in kilowatt-hours (kWh).

Input Values

Power (hp) mechanical horsepower

Time (hours) e.g. 1.5 for 90 min

Result

Enter values and press Calculate

Formula

Energy Formula

kWh = hp × 0.74569987 × h

Intermediate — Power

kW = hp × 0.74569987

Conversion Factor

1 hp = 745.69987 W

Result copied!

Summary

Enter power in horsepower and duration in hours to calculate the equivalent energy in kilowatt-hours (kWh).

How it works

Enter the power output in horsepower (hp).
Enter the operating duration in hours (h).
Press Calculate to see the energy result in kilowatt-hours (kWh).
The breakdown panel shows kilowatts (kW) and the applied formula.
Use the Copy Result button to copy the kWh value to your clipboard.
Press Reset to clear all fields and start a new calculation.

Use cases

Estimate the electricity equivalent of an engine or motor rated in horsepower.
Calculate how many kWh a generator produces during a given run time.
Compare mechanical and electrical energy costs for industrial equipment.
Determine battery capacity needed to replace a gasoline engine of known horsepower.
Size power supply systems by converting motor horsepower to kilowatt demand.
Compute daily or monthly energy consumption of pumps and compressors.
Convert vehicle engine output to kWh for EV range equivalence studies.
Verify energy balance calculations in mechanical and electromechanical systems.

Frequently Asked Questions

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Amps To Kilowatt Hours Amps To Kilowatts Kilowatts To Amps

Last updated: 2026-05-23 · Reviewed by Nham Vu