With this tool you can convert HP to kW automatically, easily, quickly and for free.
For greater ease we explain that formula is used for the calculation, how convert from Hp to kW in 1 step , besides some examples and a table with the main conversions from HP to kW
We also show the most common efficiency values in the engines.
Formulas to convert, calculate, transform from Hp to kW:
- kW: Kilowatts or 1000Watts
- Hp: Horsepower or horse power
- E: Motor efficiency.
How to convert from Hp to kW in 1 single step:
Step 1:
In general there are three types of Hp, however the most used is the electric Hp therefore to convert from electric Hp to kW you must use the formula: H.px0,746 / E and simply replace the variables in this formula.
By example, you have an electric motor of 40Hp, with an efficiency of 88.5%, to know the equivalence in kW, you must multiply 40Hpx0,746 and divide the result between 88.5% giving as result: 33.5kW.
Examples of conversions from Hp to kW:
Example 1:
Four motors of 1.5 Hp and 80% efficiency are connected to a transformer, how many kW in total have the motors ?.
Answer: // First you must add the Hp of all the engines, which will result in 6Hp, then multiply the Hp by 0.746 and finally divide this result by 80% efficiency, as follows: (6 × 0.746) / 0.8 = 5.6kW.
Example 2:
An electric motor is 14Hp, with an efficiency of 86%, how many kW does the motor have?
Answer: // It’s easy to multiply 14 × 0.746, and then divide the result by 0.86 (It’s 86% in decimals). Which will give as a result: 12,14kW.
Example 3:
An engine has a power of 3.5Hp mechanical, how much power in kW will the engine?
Answer: // To move from mechanical Hp to kW simply multiply the Hp by the constant 0.745699, which will result in: 2.609kW.
Common efficiencies for motor:
Electric motors built according to NEMA Design B must meet the following efficiencies:
| Power (Hp) | Minimum Nominal Efficiency 1) |
| 1-abr | 78.8% |
| 5-sep | 84.0% |
| oct-19 | 85.5% |
| 20 – 49 | 88.5% |
| 50 – 99 | 90.2% |
| 100 – 124 | 91.7% |
| > 125 | 92.4% |
1) Design NEMA B, individual speed 1200, 1800, 3600 RPM. Open drip-proof (ODP) or fully enclosed fan-cooled (TEFC) 1 hp and larger motors that operate more than 500 hours per year.
Hp to kW, table for conversion, equivalence, transformation :
Equivalence of Hp to kW for three-phase motors:
| How many Hp are: | Equivalence en kW |
| 1/8 1/6 1/4 1/3 1/2 3/4 1 1.5 2 3 4 5 5.5 7.5 10 12.5 13.5 15 20 25 30 40 50 60 75 100 125 150 175 200 | Equivalence to 0.1 kW 0.12 kW 0.18 kW 0.25 kW 0.37 kW 0.56 kW 0.75 kW 1.1 kW 1.5 kW 2.2 kW 3.0 kW 3.7 kW 4.0 kW 5.5 kW 7.5 kW 9.3 kW 10 kW 11 kW 15 kW 18 kW 22 kW 30 kW 37 kW 45 kW 55 kW 75 kW 90 kW 110 kW 130 kW 150 kW |
Equivalence of Hp to kW for single-phase motors:
| How many Hp are: | Equivalence en kW |
| 1/12 1/8 1/6 1/4 1/3 1/2 3/4 1 | Equivalence to 0.07 kW 0.1 kW 0.12 kW 0.18 kW 0.25 kW 0.37 kW 0.56 kW 0.75 kW |
| 1.5 2 3 4 5 5.5 7.5 10 | 1.1 kW 1.5 kW 2.2 kW 3 kW 3.7 kW 4 kW 5.5 kW 7.5 kW |
The tables are based on engines of approximately 1450rpm efficiency and average power factor.
Wide variations of these tables can arise, especially in single-phase motors, therefore engineers should, whenever possible, check the motor nameplate in each case.
Qualify calculator from Hp to kW: [kkstarratings]