Kilowatts vs. Megawatts: What’s the Difference?

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Kilowatts vs. Megawatts: What’s the Difference?

We measure electricity in watts, named after the steam engine inventor James Watt. A watt is the primary power unit in the international system of units. It indicates the rate at which electricity is spent or the rate at which electrical energy is absorbed, radiated or dissipated. Kilowatts and megawatts are variations of the watt. However, watts are pretty small units of electrical measurement. Most homes use thousands of watts daily. Instead of listing the large units in watts, you convert them to kilowatts and megawatts. So, if your household needs 10,000 watts, you write 10kW (ten kilowatts).

In this article, we will explore the differences between kilowatts and megawatts, which are the larger power values for the watt.

Kilowatts vs. Megawatts: Side-By-Side Comparison

Kilowatts (kW)Megawatts (MW)
Number of Watts1,0001,000,000
Bigger Units than ItMegawatt, Gigawatt, TerawattGigawatt, Terawatt
Smaller Units than ItMilliwatts, WattsMilliwatts, Watts, Kilowatts
Conversion1 Kilowatt= 0.001 Megawatts1 Megawatt= 1,000 Kilowatts
Kilowatt hour kilowatt per hour
The electric meter in your home measures your electricity usage in kWh.


Kilowatts vs. Megawatts: What’s the Difference?

Kilowatts Explained

A kilowatt, abbreviated as kW, is an electric energy measurement unit equivalent to 1,000 watts. It is a standard measure of how much power large appliances and households need. For instance, a 1,000 watts water heater is also a 1kW water heater. Electrical appliances with higher kilowatt ratings require more electrical energy to operate. You measure your home electricity bill in kilowatt-hours (kWh). This means 1kWh is an hour of electricity use at a 1,000 watts rate.

Here is a list of what you can do with a one-kilowatt hour of electricity:

  • Power a 100-watt bulb for 10 hours
  • Power an average US residential home for 50 minutes (average electricity consumption was 10,632-kilowatt hours (kWh) annually).
  • Run a home pool pump for up to 3.4 hours (home pool pumps consume 2,500kWh per year to run).

Megawatts Explained

Megawatt is a larger unit of electricity used to quantify the output of a big power plant or the electrical energy required to run an entire city. One megawatt is equal to 1,000 kilowatts and 1,000,000 watts. The term megawatt was conceived by analogy with megabyte and megohm that was used to describe vast amounts of computer memory. 

Here is a list of what you can do with a one-megawatt hour of electricity:  

  • Power a 100-watt bulb for 10,000 hours
  • Power an average home for 36 days
  • Run a home pool pump for up to 5 months (home pool pumps consume 2,500kWh per year to run).

Kilowatts Real-World Examples

Air Conditioners

Central air conditioners are devices for heating and cooling homes. An air conditioner generally uses between 3 and 4 kilowatts per hour. Window units use between 0.9 and 1.44 kilowatts per hour, while portable AC uses between 2.9 and 4.1 kilowatts per hour. 

Factors that raise or lower the amount of power an air conditioner uses include efficiency rating, climate, maintenance routine, temperature settings, and insulation. For instance, servicing your AC regularly involves changing filters and removing dirt and debris. This increases its efficiency and reduces the number of kilowatts used per hour.


The average refrigerator uses between 01-0.4 kilowatts per hour. This translates to 1.2-4.8 kilowatts per day. However, some factors determine the number of kilowatts a refrigerator consumes. They include age, size, type, and the kitchen’s ambient temperature. Additionally, refrigerators have varying power requirements. For instance, small fridges use less energy compared to large fridges. The newer energy star certified fridges use power more efficiently, while older fridges have low energy efficiency. 


The average dishwasher uses between 1.2kWh and 1.5kWh per load. Therefore, a 1200-watt dishwasher at a load time of one hour uses 1.2kWh. The real estimate of energy a model uses depends on the type of cycle you choose to run or the manufacturer’s design. The type of dishes you load and settings for the soil level will determine variables such as the amount of water and the water pressure. 

Heated drying consumes more energy, increasing the number of kilowatts used. A poorly maintained dishwasher uses more electricity because of the clogging of filters with food particles and soap scum. Clogging reduces energy efficiency and prevents an effective washing cycle.

Electric Stove

Electric stoves use between 2 and 5 kilowatts of electric energy, translating to an average of 3kW per hour. If your electric stove functions at 12 cents per kWh, it will cost you 36 cents per hour. The size of the burner also affects the number of kilowatts used. Bigger burners use more power, while small burners use less power. Since cooktops range between 1.2-3 kilowatts, the cost per hour will be roughly 14-36 cents. 

Other determinants for energy consumption include frequency of use, the temperature you set while baking, and duration of use. For example, the more you use your stove, the more kilowatts it will draw. 


Microwaves are energy-efficient home appliances, but their energy depends on the power setting, size, and frequency of use. Small microwaves use between 0.6 to 0.8kW, standard ones use 0.8-1kW, while commercial ones use over 1kW per hour. Therefore, if your microwave draws 1.2 kilowatts per hour and is used for 15 minutes daily, it uses 0.3kWh daily and 109.5kWh per year. 

Megawatts Real-World Examples

Data Centers

Data center providers deliver service-level agreements and uptime warranties to large companies worldwide. Their role is to store, process, and communicate information we use every day, including scientific computing, streaming video, social media, and emails. They use information technology devices that are powered by electricity. 

Servers and cooling systems account for the biggest share of energy use, followed by network appliances and storage drives. Global internet demand is growing, and so is the need for devices and electric energy. Large centers have thousands of storage gadgets that use over 100 megawatts of electricity.

Hospitals and Healthcare Facilities

Large hospitals have many appliances and facilities that need high electrical energy to run. Electricity is required in almost all aspects of patient care, hence the need for megawatts of power. Whether sustaining life in an ICU or performing critical procedures in ER rooms, healthcare facilities need a large power supply. Hospitals serve thousands of patients who check in throughout the year. If an average hospital uses 31kWh of electricity per square foot annually, a hospital that covers 3000 square feet of space uses 93 megawatts per year.


In the manufacturing industry, power is needed to run the continuous automation equipment in the production cycle, whether for brewing beers, precision chemistry equipment, or microprocessors. Large equipment uses multiple megawatts. For instance, a recent survey indicated that the average monthly consumption for factories was 80.543 megawatts. However, the actual electrical energy used depends on the size, location, and type of industry. 

Event Venue Broadcast

For the event venue and broadcast industry, nothing is more important than an efficient supply of onsite electricity to run their power-demanding activities. Stadiums with large display systems and showcases of light and flare rely on a high power range. During big game days such as the world cup, stadiums use up to 10 megawatts of electricity. This energy accounts for floodlights, video walls in training and management areas, sound systems, satellite connectivity, refreshments, and hospitality.

largest electricity companies
Electricity power generating station in Phoenix, AZ.


Kilowatts vs. Megawatts: 6 Must-Know Facts

  • We abbreviate a kilowatt as kW, while a Megawatt is abbreviated as MW.
  • Milliwatt is the smallest unit used to measure electric energy. 
  • One kilowatt is equal to 1,000,000 (one million) milliwatts. In contrast, one megawatt is equal to 1,000,000,000 (one billion) milliwatts.
  • While working on the steam engine, James Watt, a renowned inventor, discovered the notion of horsepower as a unit of energy output. The watt was later named after him.
  • 2 megawatts of electricity can power 60,000 homes.

Bottom Line

We widely use kilowatts and megawatts in our daily lives. However, their functionality differs based on the energy required by a device, a facility, or a population. A kilowatt is a unit of measurement applied in small gadgets, while we use a megawatt in large industries.

Frequently Asked Questions

What is the difference between kilowatts and megawatts?

Megawatts are used to measure output of  power plants and cities energy needs while kilowatts are  smaller units of the Megawatt used to measure power consumption of household appliances.

Is a megawatt or a kilowatt larger?

A megawatt is larger than a kilowatt. One kilowatt(1kW)= 0.001 Megawatts(MW) or 1,000watts.  That’s to say 1MW =1,000 kilowatts. 

What's the difference between watts and kilowatts?

A watt is the smallest basic unit used to measure electricity. A kilowatt is a higher quantity of the watt. 1kilowatt =1,000 watts of electrical energy.

How many units are in a kW?

One unit of electric energy equals to one kWh. This is the amount of power needed to use a device of 1,000 watts power rating for an hour. So, one unit of electricity =1kWh.

What does 500 MW power plant mean?

Every power plant has its capacity indicating the maximum power output when working at optimal level. Therefore a 500 MW power plant means that the power plant is capable of producing 500 megawatts when working at full capacity.

How many MW does a house use?

In 2021, the average annual power usage for a resident in the united states was 10,632. This is an average of 886kWh per month.

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