Kilowatts to Horsepower Conversion

Kilowatts

One kilowatt is the power equal to 1,000 watts, or the energy consumption at a rate of 1,000 joules per second.

The kilowatt is a multiple of the watt, which is the SI derived unit for power. In the metric system, "kilo" is the prefix for 10³. Kilowatts can be abbreviated as kW; for example, 1 kilowatt can be written as 1 kW.

Horsepower

The term horsepower was adopted by Scottish inventor James Watt to measure the power output of his steam engine and to compare that power with that of horses horses.^[1] Horsepower were later used to measure the power output of piston and turbine engines and electrical motors.

There are now several different types of horsepower, including mechanical, electrical, metric, boiler, brake, and indicated, and they all have different applications in industry. Mechanical and electric are the most commonly used types.

Mechanical Horsepower

Mechanical horsepower is often used to measure the output of engines and motors in North America. One mechanical horsepower is equal to 745.69987158227022 watts.

The mechanical horsepower is a US customary and imperial unit of power. Mechanical horsepower can be abbreviated as hp(I); for example, 1 mechanical horsepower can be written as 1 hp(I).

Electric Horsepower

Electric horsepower is used to measure the output of electric motors and other electrical machines in the US. One electric horsepower is equal to exactly 746 watts.

The electric horsepower is a US customary and imperial unit of power. Electric horsepower can be abbreviated as hp(E); for example, 1 electric horsepower can be written as 1 hp(E).

Metric Horsepower

One metric horsepower is the power needed to one metric horsepower as the lift a 75 kilogram mass at at one meter per second.^[2] One metric horsepower is equal to 735.49875 watts.

The metric horsepower is a non-SI metric unit for power. Metric horsepower can be abbreviated as hp(M), and are also sometimes abbreviated as PS, cv, hk, pk, ks, or ch. For example, 1 metric horsepower can be written as 1 hp(M), 1 PS, 1 cv, 1 hk, 1 pk, 1 ks, or 1 ch.

Boiler Horsepower

Boiler horsepower is used to measure the power of a boiler to generate steam. One boiler horsepower is equal to the power needed to evaporate 34.5 pounds in one hour.^[3]

Boiler horsepower can be abbreviated as hp(S); for example, 1 boiler horsepower can be written as 1 hp(S).

Try our engine horsepower calculator to calculate the power of a motor.