What is kilowatt?

A kilowatt is a unit of power equal to 1,000 watts. It is commonly used to rate electric motors, heating systems, solar panels, EV chargers, and industrial equipment.

Real-world uses

Kilowatts are used for rating home electrical systems, electric vehicle charging speeds (Level 2 chargers: 7–22 kW), solar panel array output, electric motors in appliances, and small generators. A typical household may have a peak demand of 3–10 kW.

History

As electricity supply systems expanded in the late 19th century, the kilowatt became the practical unit for measuring power demands and generation capacities beyond the range of single watts. Its adoption enabled standardised rating of motors, generators, and electrical infrastructure.

Common mistakes

Confusing kilowatts (kW, power) with kilowatt-hours (kWh, energy). A 7 kW EV charger running for 2 hours delivers 14 kWh of energy. Also, mixing up kW and kVA in electrical specifications—kVA is apparent power, not real power.

What is gigawatt?

A gigawatt is a unit of power equal to one billion watts. It is used to express the total power output of national electricity grids, large power stations, and national energy policy targets.

Real-world uses

Gigawatts describe the generating capacity of entire national grids, large hydroelectric dams (Three Gorges Dam: ~22.5 GW), and the total installed solar or wind capacity of countries. Global electricity demand is often expressed in terawatts (1,000 GW). Energy policy discussions use GW to compare national ambitions.

History

Gigawatts entered common use in discussions of national and continental electricity systems during the 20th century. As installed generation capacity in large countries reached the gigawatt scale, this unit became standard for energy policy, grid planning, and international energy statistics.

Common mistakes

Confusing GW (power) with GWh (energy). A 22 GW dam running at full capacity for one hour generates 22 GWh of energy. Also, the pop-culture reference "1.21 gigawatts" from Back to the Future is frequently cited but would equal about 1,210 MW—a large power plant.

When is this conversion used?

Converting kilowatt to gigawatt is useful in the power domain when comparing values across different measurement standards or applying formulas that require a specific unit.

Worked examples

1 kilowatt = 0.000001 gigawatt

1 gigawatt = 1.000000e+09 watt

How to convert kilowatt to gigawatt

To convert kilowatt to gigawatt, multiply the value by 0.000001.

To convert gigawatt back to kilowatt, multiply by 1,000,000.

Measurement standards

The watt is the SI derived unit of power, defined as one joule per second (kg·m²/s³). Horsepower remains in widespread informal use, particularly in the automotive industry, but has no single universal definition across regions.

Did you know?

The human body at rest produces about 80 watts of power — roughly enough to keep an incandescent light bulb glowing. During intense exercise, a trained cyclist can sustain over 400 watts, and elite sprinters briefly exceed 2,000 watts.

Quick reference: kilowatt to gigawatt

kilowattgigawatt
0.11.000000e-07
0.55.000000e-07
10.000001
20.000002
50.000005
100.00001
250.000025
500.00005
1000.0001
2500.00025
5000.0005
1,0000.001

Common values

kilowattgigawatt
LED light bulb0.01 kilowatt1.000000e-08 gigawatt
Desktop computer0.3 kilowatt3.000000e-07 gigawatt
Microwave oven1 kilowatt0.000001 gigawatt
Small car engine75 kilowatt0.000075 gigawatt
Wind turbine (large)3,000 kilowatt0.003 gigawatt