Understanding power units
Mechanical horsepower is approximately 745.699872 W; metric horsepower (PS) is 735.49875 W. They are not interchangeable. Power is a rate; multiply kW by hours to obtain kWh of energy.
Conversion method
For linear units, multiply the input by its factor to the base unit, then divide by the target factor. The table lists definitions where exact and approximate constants where applicable.
| Unit | 1 unit in base units | Definition |
|---|---|---|
| Watt (W) | 1 | Exact definition; display may be rounded |
| Kilowatt (kW) | 1,000 | Exact definition; display may be rounded |
| Megawatt (MW) | 1,000,000 | Exact definition; display may be rounded |
| Horsepower (mechanical) (hp) | 745.6998715823 | Approximate / conventional value |
| Metric horsepower (PS) | 735.49875 | Exact definition; display may be rounded |
| BTU per hour (BTU/h) | 0.2930710702 | Approximate / conventional value |
| Foot-pound per second (ft·lbf/s) | 1.3558179483 | Approximate / conventional value |
| Kilocalorie per hour (kcal/h) | 1.1622222222 | Exact definition; display may be rounded |
Worked example and common conversions
10 hp = 7.4569987158 kW. Keep full precision during conversion, then round the final result to the precision of your measurement.
| From | To |
|---|---|
| 10 hp | 7.4569987158 kW |
| 10 kW | 13.410220896 hp |
| 10 W | 34.1214163313 BTU/h |
| 10 BTU/h | 2.9307107017 W |
| 10 kW | 34,121.4163312794 BTU/h |