With this tool you can convert kW to HP (Horsepower) or from Hp to kW automatically, easily, quickly and free.
For greater ease we explain the formula from kW to Hp, some examples of kW to Hp, how to do the conversion, a table of equivalences and show the most common efficiency values in the motors.
Formulas to convert, calculate, transform from kW to Hp:
- kW: Kilowatts or 1000Watts
- Hp: Horsepower or horse power
- E: Engine efficiency.
How to convert from kW to Hp in 1 only step:
Step 1:
There are three types of Hp, the most used is the electric Hp therefore to convert from electric kW to Hp you must use the formula: kWxE / 0,746 and then replace the variables in the formula. As follows: you have an electric generator of 38.5kW, with an efficiency of 84%, to know the equivalence in Hp, you must multiply 38.5kWx0.84 (84%) and divide the result by 0.746, resulting in: 43.35Hp.
Examples of conversions from kW to Hp:
Example 1:
An industrial engine has a power of 21.6kW and 82% efficiency how many hp has the engine ?.
Answer: // First you must multiply the kW by 82% (0.82) and finally divide this result by 0.746, as follows: (21.6 × 0.82) / 0.746 = 23.74kW.
Example 2:
An electric motor of a fan is 18.8kW, with an efficiency of 89.3% (0.89), how many Hp has the motor?
Answer: // You must multiply 18 × 0.89 (It is 0.89 in decimals), and then divide the result by 0.746. Which will result in: 21.47Hp.
Example 3:
A motor of a compressor has a power of 84kW, how much power in Hp will the motor have?
Answer: // To move from mechanical kW to Hp you simply have to divide the kW by the constant 0.745699, which will result in: 2.609kW.
Common efficiencies for engines:
Electric motors built according to NEMA Design B must meet the following efficiencies:
| Hp | Minimum Nominal Efficiency 1) |
| 1 – 4 | 78.8% |
| 5 – 9 | 84.0% |
| 10 – 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.
kW to Hp, table for conversion, equivalence, transformation:
Equivalence of kW to Hp for three-phase motors:
| How many kW are: | Equivalence in Hp: |
| How many are 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 | Equivalent to 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 of kW to Hp for single-phase motors:
| How many kW are: | Equivalence in Hp: |
| How many are 0.07 kW 0.1 kW 0.12 kW 0.18 kW 0.25 kW 0.37 kW 0.56 kW 0.75 kW | Equivalent to 1/12 1/8 1/6 1/4 1/3 1/2 3/4 1 |
| 1.1 kW 1.5 kW 2.2 kW 3 kW 3.7 kW 4 kW 5.5 kW 7.5 kW | 1.5 2 3 4 5 5.5 7.5 10 |
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 kW to HP: [kkstarratings]