6 min read
2026-02-09
SI unit. 1 W = 1 J/s. Kilowatt (kW) = 1000 W. Megawatt (MW) = 1,000,000 W.
Metric: 1 HP = 735.499 W. Mechanical (HP): 1 HP = 745.7 W. Used for engines.
British thermal unit per hour. 1 BTU/h = 0.2931 W. Used for heating systems.
1 kcal/h = 1.163 W. Found in old reference books.
| Unit | In watts |
|---|---|
| 1 hp (metric) | 735.5 |
| 1 HP (mechanical) | 745.7 |
| 1 BTU/h | 0.2931 |
| 1 kcal/h | 1.163 |
| 1 kW | 1,000 |
LED bulb: 10 W
Microwave: 800–1200 W
Vacuum cleaner: 1500–2200 W
Car: 100–300 hp (73.5–220.6 kW)
Electric train: 4000–8000 kW
Nuclear power plant: 1000 MW
See also: Energy Converter, Pressure Converter, Fuel Converter