A kilowatt (kW) is a unit of power defined by the International System of Units (SI). The basic unit of the kilowatt is the watt (W), named after the Scottish inventor James Watt. The prefix kilo means one kilowatt is one thousand watts or joules per second.

What does a kilowatt (kW) mean?

Kilowatts are used worldwide primarily to express the power of motors, tools, machines, and heaters. The European Union defines kilowatts (kW) as the official unit for engine power, but even so, horsepower is preferred in common communication.

What does kWh mean?

Electricity used in a home is usually measured in kilowatt-hours or kWh, which means 1000 watts are used in one hour. Megawatt or gigawatt hours, on the other hand, are used in large buildings or industries.

A horsepower is a unit of measurement of power. One horsepower (HP) corresponds to the force needed to lift 550 pounds one foot in one second or 33,000 pounds one foot in one minute.

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Horsepower: What is it, and why is it important?

The horsepower used in the US (SAE standard) and metric horsepower (PS - Pferdestärke) used in Europe are different. Metric horsepower (DIN standard) is 98.6% of one HP or the other way round — 1.4% less than the SAE horsepower. Simply put 1 Imperial horsepower = 1.014 Metric horsepower.

Electrical Horsepower

One horsepower equals 746 watts (W)or 0.746 kilowatts (kW) in SI (International System of Units). There is no difference between electrical and mechanical horsepower. To calculate horsepower from watts, multiply the value in watts by 0.00134. On the other hand, to get watts, multiply the horsepower value by 746.

The history of horsepower

Horsepower was first coined by Scottish inventor James Watt in the late 18th century to help market his improved steam engine. At the time, it made sense to measure the output of a steam engine in horsepower because the value meant the number of horses the engine could replace. This made it very easy for potential buyers to understand the performance of the engine.