Kw to Hp Conversion Formula and Examples

To convert kw to hp, you can use the following conversion factor:

1 kilowatt (kW) is approximately equal to 1.34102 horsepower (hp).

So, to convert kilowatts to horsepower, you can multiply the number of kilowatts by 1.34102. For example, if you have 100 kW, you can convert it to horsepower as follows:

100 kW × 1.34102 ≈ 134.102 hp

So, 100 kilowatts is approximately equal to 134.102 horsepower.

kw to hp converter online:

kw to hp conversion formula

Conversion from kW to hp:

  1. How many kilowatts are in 1 horsepower? The conversion factor is 1 hp = 0.746 kW.

  2. The formula for converting kW to hp: is HP = KW * 0.746

  3. To use the kW to hp formula:

    • Divide the KW value by 0.746.

Conversion from hp to kW:

  1. To convert from horsepower (hp) to kilowatts (kW), multiply the hp value by 0.746.

Examples of hp to kW conversion:

Example 1:

  • How many kW is a 1 hp motor?
  • Calculation: 1 hp = 1 * 0.746 = 0.746 kW.

Example 2:

  • How many kW is a 20 hp motor?
  • Calculation: 20 hp * 0.746 = 14.9 kW.

Example 3:

  • How many kW is a 100 hp motor?
  • Calculation: 100 hp * 0.746 = 74.6 kW.

Examples of kW to hp conversion:

Example 1:

  • An electrical motor with 15 kW, what is its power in horsepower?
  • Calculation: 15 kW / 0.746 = 20.1 hp.

Example 2:

  • An electrical load with a power of 100 kW, how many hp is it?
  • Calculation: 100 kW / 0.746 = 134.05 hp.

hp to kw 3 phase formula and example

The formula for converting horsepower (hp) to kilowatts (kW) is the same for both single-phase and three-phase systems.

The formula HP = KW * 0.746 is the general formula for converting hp to kW, and it applies to both single-phase and three-phase systems.

The standard conversion factor for this purpose is approximately 0.7457 for both single-phase and three-phase systems.

Example: Suppose you have a motor with a power rating of 15 horsepower (hp), and you want to convert the motor’s power to kilowatts (kW) without considering efficiency.

Using the formula:

kW=15 hp0.7457

  1. = 15 horsepower
  2. Conversion Factor = 0.7457

Now, plug these values into the formula:


Calculate the result:


So, the motor’s power is approximately 20.09 kW when considering only the conversion factor and not motor efficiency. This formula works for both single-phase and three-phase systems.

Electric motor Power consumption

Motor power consumption =  Motor power * Running hours.

Example 1

A 1 HP motor, means a 746 Watt power.

This motor will consume power in one hour equals 746 Watt Hour.

Example 2

How much power will A 5 HP motor consume in 20 minutes? 

Motor Power Consumption = Motor Power(in KW) * Operating Time

Converting 5 HP to KW = 5 *0.746 KW = 3.73KW

Motor consumption in 20 minutes = 3.73 * (20/60) – to convert minutes into hours =1.243KWH

Example 3

How much Power does a 25 hp motor use?

Motor Power Consumption = Motor Power * Time

Converting 25 HP to KW = 25 *0.746 KW = 18.65 KW

A 25 hp motor consumption in 1 hour = 18.65*1 =18.65 KWH

How to increase the power of an electric motor?

Increasing the power of an electric motor can be a complex process that may involve various engineering considerations.

The power of an electric motor is typically determined by its design, components, and operating conditions.

Here are some general guidelines and methods to consider when attempting to increase the power of an electric motor:

  1. Select a Higher-Rated Motor: The simplest way to increase motor power is to replace the existing motor with one that has a higher horsepower (hp) rating. This new motor should be compatible with the system and application requirements.

  2. Increase Voltage: Increasing the voltage supplied to the motor can increase its power output. However, this should only be done within the motor’s design voltage limits, and it may require modifications to the electrical supply system to accommodate the higher voltage.

  3. Upgrade to a Higher-Efficiency Motor: Motors with higher efficiency ratings can often deliver more power for the same input energy. Consider replacing older, less efficient motors with newer, more efficient models to achieve increased power while reducing energy consumption.

  4. Modify the Motor Windings: In some cases, it may be possible to modify the motor windings to increase power output. This should only be attempted by experienced professionals and may require specialized knowledge of motor design.

  5. Improve Cooling: Overheating can limit the power output of a motor. Enhancing the motor’s cooling system, such as adding additional fans or cooling fins, can help it handle higher power loads.

  6. Use Variable Frequency Drives (VFDs): VFDs allow you to control the speed and power output of a motor by adjusting the frequency of the electrical supply. By using a VFD, you can operate the motor at higher power levels when needed and at lower power levels when not in use, potentially increasing overall efficiency.

  7. Ensure Proper Maintenance: Regular maintenance, including cleaning, lubrication, and alignment, can optimize a motor’s performance. Neglected motors may not operate at their full potential.

  8. Check Mechanical Components: Inspect and maintain the mechanical components connected to the motor, such as belts, pulleys, and couplings. Replacing or upgrading these components can help transmit more power to the load.

  9. Consider Mechanical Gear Reduction: In some cases, adding a mechanical gear reduction system can increase the power output of a motor by trading off speed for torque.

  10. Consult a Professional: Increasing motor power can have safety and reliability implications. It’s essential to consult with a qualified electrical engineer or motor specialist before attempting any significant modifications to ensure that the modifications are safe, compliant with regulations, and will not damage the motor or the connected equipment.

Remember that modifying or increasing the power of an electric motor should be done with caution and expertise, as it can have implications for safety, motor lifespan, and system reliability.

Always follow the manufacturer’s recommendations and consult with professionals when making significant changes to motor systems.

Why do we convert motor power to kilowatts?

Converting motor power to kilowatts (kW) is a common practice because the kilowatt is a more universally recognized and scientifically consistent unit for measuring power when compared to other units like horsepower (hp). Here are several reasons why kW is often used for measuring motor power:

  1. Metric System Consistency: The kilowatt is a unit of power within the International System of Units (SI), which is the modern metric system used worldwide for scientific and engineering purposes. The SI system is based on standard, consistent units, making it easier for professionals in various countries to communicate and collaborate.

  2. Standardization: Kilowatts provide a standardized and consistent way to express power across different applications and industries. This consistency simplifies engineering calculations and allows for easy comparisons between motors and other electrical devices.

  3. Ease of Conversion: Converting between electrical power and other energy-related units is straightforward when using kilowatts. For example, 1 kilowatt-hour (kWh) is equal to 3.6 million joules, simplifying energy calculations.

  4. Global Compatibility: The use of kilowatts is compatible with international standards and regulations, making it easier for manufacturers to produce motors for a global market.

  5. Precision: Kilowatts are a more precise unit for measuring power compared to horsepower, which can vary slightly depending on the country and industry. Using kilowatts allows for more accurate power calculations.

  6. Energy Efficiency: Many countries and regions have energy efficiency regulations and standards that specify power ratings in kilowatts. This encourages the design and use of more energy-efficient motors and appliances.

  7. Electricity Billing: In many parts of the world, electricity consumption is billed in kilowatt-hours (kWh), which directly relates to the power of electrical devices in kilowatts. Using kilowatts for motor power ratings aligns with this billing system.

While kilowatts are widely used for motor power ratings, it’s worth noting that horsepower (hp) is still used in some regions, particularly in the United States, where imperial units are more common. However, even in these regions, kW ratings are often provided alongside hp ratings, especially for industrial and commercial equipment, to ensure compatibility with international standards and practices.

In summary, converting motor power to kilowatts is a practice that promotes consistency, precision, and compatibility with global standards, making it easier for professionals to work with motor specifications in various contexts.

Why does motor power in hp?

Motors are often rated in horsepower (hp) because this unit of measurement has historical significance in the context of mechanical power and engineering.

The use of horsepower to measure motor power can be traced back to the 18th century when the Scottish engineer James Watt developed the concept of horsepower as a way to market and compare the efficiency of steam engines, which were widely used during the Industrial Revolution.

Here are a few reasons why horsepower is traditionally used to rate motor power:

  1. Historical Significance: As mentioned, horsepower was popularized by James Watt and became widely accepted as a measure of power for engines during the early days of the Industrial Revolution. This historical context has led to its continued use.

  2. Familiarity: Many people, including engineers and consumers, are familiar with the concept of horsepower, and it provides a way to easily understand and compare the power of different motors and engines.

  3. Legacy Systems: Many industries and standards organizations have developed around the use of horsepower as a unit of power. This includes standards for motor efficiency, performance, and sizing.

  4. Consistency: Using horsepower provides a consistent unit of measurement for motor power, making it easier for manufacturers and consumers to communicate about motor specifications.

  5. Tradition: Over time, the use of horsepower has become deeply ingrained in engineering and industrial practices, and changing to a different unit of measurement would require a significant shift in industry standards and practices.

While the use of horsepower for motor ratings has a long history, it’s worth noting that in many countries, especially in Europe, the International System of Units (SI) is more commonly used, and motors may also be rated in kilowatts (kW) alongside or instead of horsepower.

Kilowatts are a more straightforward and scientifically consistent unit for measuring power, as they are based on the metric system.

However, horsepower remains in common use in the United States and some other countries with historical ties to imperial units.

To determine the horsepower (hp) rating of an electric motor, you can follow these steps:

  1. Check the Motor Nameplate: The most straightforward way to find the horsepower rating of an electric motor is to examine its nameplate or data plate. This plate is typically located on the motor housing and contains important information about the motor, including its horsepower rating.

  2. Read the Nameplate Data: Look for a section on the nameplate that specifies the motor’s power rating. It may be labeled as “HP” or “Horsepower.” The horsepower rating is usually provided in hp (e.g., 1 HP, 2 HP, 5 HP, etc.).

  3. Consult the Manufacturer’s Documentation: If you can’t find the horsepower rating on the nameplate or if the nameplate is damaged or illegible, refer to the manufacturer’s documentation for the motor. This documentation may include a datasheet or manual that provides detailed information about the motor’s specifications, including its horsepower rating.

  4. Use a Multimeter: If you have access to a multimeter and are comfortable with electrical measurements, you can estimate the horsepower of the motor by measuring its electrical characteristics. Keep in mind that this method may not provide the exact horsepower rating but can give you a rough estimate. Here’s how you can do it:

    • Measure the motor’s voltage (V) and current (I) while it is running.
    • Calculate the electrical power (P) using the formula: P (in watts) = V (in volts) × I (in amperes).
    • Convert the power from watts to kilowatts (kW) by dividing by 1,000 (since 1 kW = 1,000 watts).
    • To estimate horsepower, divide the power in kilowatts (kW) by 0.7457 (1 hp ≈ 0.7457 kW). For example, if the motor’s power is 5 kW, it’s approximately 6.71 hp (5 kW / 0.7457 ≈ 6.71 hp).
  5. Contact the Manufacturer or Supplier: If you are unable to determine the motor’s horsepower rating using the methods above, you can contact the manufacturer of the motor or the supplier from whom you purchased it. They should be able to provide you with the exact specifications, including horsepower.

It’s important to note that the nameplate or manufacturer’s documentation is the most reliable source for determining the motor’s horsepower rating, as it provides the manufacturer’s intended and certified specifications. Using other methods, especially if not done accurately, may result in an approximate value.

I have written a detailed article about motor nameplate understanding. I highly recommend reading it.

Hereunder is a 30 HP motor nameplate.
motor power in HP on the nameplate
motor power in HP on the nameplate