Power Unit Converter
Convert power units between different measurement systems
| Name | Symbol | Result |
|---|---|---|
| Watt (Base unit of power in SI system) | W | 0,00 |
| Kilowatt (Unit used for larger power (1000 W)) | kW | 0,00 |
| Megawatt (Unit used in power engineering (1000 kW)) | MW | 0,00 |
| Gigawatt (Unit for large power stations (1000 MW)) | GW | 0,00 |
| Horsepower (Unit used in automotive industry (745.7 W)) | hp | 0,00 |
| Metric horsepower (Continental European horsepower (735.5 W)) | PS | 0,00 |
| BTU per hour (British thermal unit of power) | BTU/h | 0,00 |
| Kilocalorie per hour (Thermal power unit (1.163 W)) | kcal/h | 0,00 |
Power Units – Overview and Applications
Power is one of the key concepts in physics and engineering. It defines how quickly work is performed or how fast energy is transferred or converted. Various units of power are used in different fields of life and technology, adapted to specific contexts. Below we discuss the most important ones.
Watt (W)
Watt (W) is the basic unit of power in the SI system (International System of Units). It is defined as one joule of energy per second:
- 1 W = 1 J/s
The watt is commonly used in science, industry, and everyday life, such as for labeling the power of electrical devices (e.g., light bulbs, computers, motors).
Kilowatt (kW)
Kilowatt (kW) equals one thousand watts:
- 1 kW = 1000 W
This unit is often used where watts would be too small for practical purposes. Power of cars, heating systems, power plants, and industrial equipment is often expressed in kilowatts.
Example: The power of an average passenger car is about 70–150 kW.
Megawatt (MW)
Megawatt (MW) equals one million watts:
- 1 MW = 1,000,000 W
Megawatts are mainly used in the energy industry, for example to describe the power of large generators, power plants, or wind turbines.
Example: A nuclear power plant may have a capacity of several thousand megawatts.
Gigawatt (GW)
Gigawatt (GW) equals one billion watts:
- 1 GW = 1,000,000,000 W
This unit describes the capacity of very large energy installations.
Example: The Three Gorges Dam in China has a capacity of over 22 GW.
Horsepower (hp)
Horsepower (hp) is a historical unit introduced by James Watt in the 18th century to describe the output of steam engines compared to the work of horses.
- 1 hp ≈ 745.7 W
Today, horsepower is mainly used in Anglo-Saxon countries to describe the power of cars and machines.
Metric Horsepower (PS or KM)
Metric Horsepower (KM or PS), used in continental Europe, differs slightly from the imperial horsepower:
- 1 KM ≈ 735.5 W
In many countries, car engine power is often given in metric horsepower (KM).
Example: An engine with 100 KM has a power output of approximately 73.55 kW.
BTU per hour (BTU/h)
BTU per hour (British Thermal Unit per hour) is mainly used in the U.S., particularly for air conditioning and heating systems.
- 1 BTU/h ≈ 0.293 W
One BTU measures the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit. In the context of power, BTU/h indicates the rate of energy delivery.
Example: A typical home air conditioner may have a capacity of 5,000 to 15,000 BTU/h.
Kilocalorie per hour (kcal/h)
Kilocalorie per hour (kcal/h) is used in dietetics and in some heating devices.
- 1 kcal/h ≈ 1.163 W
Although less commonly used in modern technology, it remains relevant in medicine and sports science to measure human energy expenditure.
Example: During a leisurely walk, a person may burn around 200–300 kcal/h.