Power Converter
Convert between different power units including Watts, Kilowatts, and Horsepower.
Result
1 Watt = 0.001 Kilowatt
Complete Guide to Power Conversion
Power conversion is essential across electrical engineering, mechanical systems, automotive industry, HVAC systems, and industrial applications. Whether you're calculating electrical power consumption, comparing engine horsepower ratings, sizing heating and cooling systems, or analyzing industrial machinery performance, our free online power converter makes it easy to convert between Watts, Kilowatts, Megawatts, Horsepower, BTU per hour, and other power units instantly. Understanding power units and conversions is crucial for accurate measurements in electrical engineering, mechanical engineering, automotive design, and thermal systems.
Understanding Power Measurement Units
Power is the rate at which energy is transferred or work is done. Different industries and applications use various power units, each suited to specific measurement scales and contexts. From tiny microwatts in electronics to massive terawatts in power plants, understanding these units helps bridge different engineering disciplines and applications.
SI Units (Metric System)
Watt (W) - The Base Unit
The Watt is the SI base unit for power, named after Scottish engineer James Watt. One Watt equals one Joule per second (1 W = 1 J/s). A 100-watt light bulb uses 100 joules of energy every second.
Watt Multiples
- Kilowatt (kW): 1,000 W - Common for appliances and small systems
- Megawatt (MW): 1,000,000 W - Power plants and large industrial facilities
- Gigawatt (GW): 1,000,000,000 W - Large power plants and national grids
- Terawatt (TW): 1,000,000,000,000 W - Global power consumption
Watt Submultiples
- Milliwatt (mW): 0.001 W - Small electronics and sensors
- Microwatt (µW): 0.000001 W - Low-power electronics
- Nanowatt (nW): 0.000000001 W - Ultra-low power devices
Mechanical Power Units
Horsepower (hp) Variants
- Mechanical Horsepower: 745.7 W - Used in US and UK
- Metric Horsepower (PS): 735.5 W - Used in Europe
- Electric Horsepower: 746 W - Electrical motors
- Boiler Horsepower: 9,812.5 W - Steam systems
Foot Pound-Force per Second
Traditional imperial unit: 1 ft·lbf/s = 1.356 W. Used in mechanical engineering for torque-based power calculations.
Thermal Power Units
BTU per Hour
Common in HVAC systems: 1 BTU/hr = 0.293 W. Used for furnaces, air conditioners, and heating equipment.
Kilocalorie per Hour
Metabolic power unit: 1 kcal/hr = 1.163 W. Used in nutrition and exercise science for metabolic rate calculations.
Electrical Power Units
Volt Ampere (VA)
Apparent power in AC circuits: 1 VA = 1 W for resistive loads. Important for power factor calculations in electrical engineering.
How to Convert Watt to Kilowatt
Converting Watts to Kilowatts is one of the most common power conversions, especially for electrical systems and appliances. To convert from Watts to Kilowatts, divide the Watt value by 1,000. This conversion factor comes from the definition: 1 kilowatt = 1,000 watts exactly. For example, 1,500 W ÷ 1,000 = 1.5 kW. This conversion is essential for understanding electrical power consumption on utility bills and appliance ratings.
Power vs Energy: Understanding the Difference
One of the most important concepts in power conversion is understanding the difference between power and energy:
- Power: The rate at which energy is transferred or work is done, measured in Watts. It's instantaneous - how fast energy is being used.
- Energy: The total amount of work done or heat transferred, measured in Joules or Watt-hours. It's cumulative - the total energy consumed over time.
The relationship is: Power × Time = Energy. For example, a 100W device running for 10 hours uses 1,000 Wh (1 kWh) of energy. Understanding this distinction is crucial for electrical calculations, energy efficiency analysis, and cost calculations.
Power Conversion Formulas
Our power converter uses these precise formulas for accurate conversions:
Watt to Kilowatt:
kW = W ÷ 1,000
Kilowatt to Watt:
W = kW × 1,000
Horsepower to Watt:
W = hp × 745.7 (mechanical horsepower)
BTU per Hour to Watt:
W = BTU/hr × 0.293071
Kilocalorie per Hour to Watt:
W = kcal/hr × 1.163
Foot Pound-Force per Second to Watt:
W = ft·lbf/s × 1.3558179483
Megawatt to Kilowatt:
kW = MW × 1,000
Power Conversion Table
Quick reference for converting between common power units:
| Unit | Watts (W) | Kilowatts (kW) | Horsepower (hp) | BTU/hr |
|---|---|---|---|---|
| 1 Watt | 1 | 0.001 | 0.001341 | 3.412 |
| 1 Kilowatt | 1,000 | 1 | 1.341 | 3,412 |
| 1 Megawatt | 1,000,000 | 1,000 | 1,341 | 3,412,000 |
| 1 Horsepower | 745.7 | 0.7457 | 1 | 2,545 |
| 1 BTU/hr | 0.293 | 0.000293 | 0.000393 | 1 |
| 1 kcal/hr | 1.163 | 0.001163 | 0.001559 | 3.968 |
| 1 ft·lbf/s | 1.356 | 0.001356 | 0.001818 | 4.626 |
Common Power Conversion Examples
Electrical Appliances (Watts to Kilowatts):
- 100W light bulb = 0.1 kW
- 1,500W hair dryer = 1.5 kW
- 2,000W microwave = 2 kW
- 5,000W electric heater = 5 kW
- 10,000W electric stove = 10 kW
- 15,000W central AC = 15 kW
- 50,000W electric car charger = 50 kW
Automotive Power (Horsepower to Kilowatts):
- 100 hp car = 74.6 kW
- 200 hp car = 149.1 kW
- 300 hp car = 223.7 kW
- 500 hp sports car = 372.9 kW
- 1,000 hp supercar = 745.7 kW
- 2,000 hp dragster = 1,491.4 kW
- 5,000 hp locomotive = 3,728.5 kW
HVAC Systems (BTU/hr to Watts):
- 5,000 BTU/hr window AC = 1,465 W
- 10,000 BTU/hr window AC = 2,931 W
- 24,000 BTU/hr central AC = 7,034 W
- 60,000 BTU/hr furnace = 17,584 W
- 100,000 BTU/hr furnace = 29,307 W
- 200,000 BTU/hr commercial = 58,614 W
- 1,000,000 BTU/hr industrial = 293,071 W
Industrial Power (Megawatts):
- 1 MW = 1,000 kW = 1,341 hp
- 5 MW wind turbine = 5,000 kW
- 50 MW power plant = 50,000 kW
- 500 MW power plant = 500,000 kW
- 1 GW power plant = 1,000 MW
- 2 GW nuclear plant = 2,000 MW
- 10 GW hydroelectric = 10,000 MW
Frequently Asked Questions (FAQ)
How do I convert Watts to Kilowatts?
To convert Watts to Kilowatts, divide the Watt value by 1,000. The formula is: Kilowatts = Watts ÷ 1,000. For example, 1,500 W = 1,500 ÷ 1,000 = 1.5 kW. One kilowatt equals exactly 1,000 watts by definition.
How many Watts are in 1 Horsepower?
One mechanical horsepower equals 745.7 watts. To convert horsepower to watts, multiply the horsepower value by 745.7. For example, 2 hp = 2 × 745.7 = 1,491.4 W. Metric horsepower (PS) equals 735.5 watts.
What is the difference between mechanical and metric horsepower?
Mechanical horsepower (hp) equals 745.7 watts and is used in the US and UK. Metric horsepower (PS or pferdestärke) equals 735.5 watts and is used in Europe. The difference is about 1.4% - mechanical horsepower is slightly larger than metric horsepower.
How do I convert BTU per hour to Watts?
To convert BTU per hour to Watts, multiply the BTU/hr value by 0.293071. The formula is: Watts = BTU/hr × 0.293071. For example, 1,000 BTU/hr = 1,000 × 0.293071 = 293.071 W. This conversion is commonly used for heating and cooling systems.
What is a Watt in simple terms?
A Watt is the SI unit of power, representing the rate of energy transfer. One Watt equals one Joule per second. In practical terms, a 100-watt light bulb uses 100 joules of energy every second. It's named after Scottish engineer James Watt.
How do I convert Megawatts to Kilowatts?
To convert Megawatts to Kilowatts, multiply the MW value by 1,000. The formula is: Kilowatts = Megawatts × 1,000. For example, 2.5 MW = 2.5 × 1,000 = 2,500 kW. Megawatts are commonly used for large power plants and industrial facilities.
What is the difference between power and energy?
Power is the rate at which energy is transferred or consumed, measured in Watts. Energy is the total amount of work done or heat transferred, measured in Joules or Watt-hours. Power × Time = Energy. For example, a 100W device running for 10 hours uses 1,000 Wh of energy.
How do I convert Kilocalories per hour to Watts?
To convert kilocalories per hour to Watts, multiply the kcal/hr value by 1.163. The formula is: Watts = kcal/hr × 1.163. For example, 500 kcal/hr = 500 × 1.163 = 581.5 W. This conversion is useful for food energy and metabolic rate calculations.
Can I use this power converter for electrical appliances?
Yes! This power converter is perfect for electrical appliances. Most appliances show power ratings in Watts or Kilowatts. Convert between units to compare power consumption. For example, a 1,500W hair dryer = 1.5 kW = 2.01 hp = 5,118 BTU/hr.
How accurate is this power converter?
Our power converter uses precise conversion factors based on international standards. Results are calculated with up to 6 decimal places and automatically formatted for optimal readability. All conversions follow official SI unit definitions and internationally recognized power unit relationships.
Real-World Applications
Electrical Engineering
Power conversion is fundamental in electrical engineering for sizing circuits, transformers, generators, and electrical equipment. Understanding power ratings helps engineers design efficient electrical systems, calculate power consumption, and ensure proper equipment sizing. Power factor considerations make VA (Volt-Ampere) conversions important for reactive loads.
Automotive Industry
Horsepower ratings are crucial in automotive design and marketing. Converting between horsepower and kilowatts helps compare engine performance across different markets. Electric vehicles use kilowatts for motor ratings, while traditional engines use horsepower. Understanding these conversions helps consumers make informed decisions.
HVAC and Thermal Systems
BTU per hour ratings are standard in heating and cooling systems. Converting to watts helps compare efficiency, calculate electrical requirements, and size equipment properly. Understanding power conversions is essential for HVAC engineers designing efficient thermal systems and calculating energy costs.
Related Unit Converters
Explore our other unit conversion tools for comprehensive measurement solutions:
- Energy Converter - Convert Joules, Calories, kWh, BTU energy units
- Voltage Converter - Convert volts, millivolts, kilovolts electrical voltage
- Current Converter - Convert amperes, milliamperes electrical current
- Frequency Converter - Convert Hz, kHz, MHz frequency units
- Force Converter - Convert Newtons, pounds-force mechanical force
- Torque Converter - Convert Newton-meters, foot-pounds torque units
Tips for Power Conversion
- Quick Approximation: For Watts to Kilowatts, divide by 1,000 (exact conversion)
- Remember Key Values: 1 hp = 746 W, 1 kW = 1,000 W, 1 BTU/hr = 0.293 W
- Horsepower Types: Mechanical (745.7 W) vs Metric (735.5 W) - check which type you need
- Electrical Efficiency: Consider power factor when converting VA to Watts for reactive loads
- Energy vs Power: Power × Time = Energy - don't confuse instantaneous power with total energy