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.
What is megawatt?
A megawatt is a unit of power equal to one million watts. It is used to rate the output of power plants, large industrial facilities, and grid-scale renewable energy installations.
Real-world uses
Megawatts describe the output of power plants, wind turbines (typically 2–15 MW each), and large solar farms. A modern natural gas peaker plant might produce 50–500 MW. Data centres may have power demands of tens to hundreds of MW. Grid operators manage supply and demand in MW.
History
As electrical grids grew through the 20th century, the megawatt became the standard unit for power station output and grid management. It enables comparisons across coal, gas, nuclear, and renewable generation sources on a common scale.
Common mistakes
Confusing MW (power) with MWh (energy). A 100 MW power plant running for 10 hours generates 1,000 MWh (1 GWh) of energy. Also, not distinguishing between MW of capacity (nameplate) and MW of actual output (which varies for renewables).
When is this conversion used?
Converting gigawatt to megawatt is useful in the power domain when comparing values across different measurement standards or applying formulas that require a specific unit.
Worked examples
1 gigawatt = 1,000 megawatt
1 megawatt = 1,000,000 watt
How to convert gigawatt to megawatt
To convert gigawatt to megawatt, multiply the value by 1,000.
To convert megawatt back to gigawatt, multiply by 0.001.
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: gigawatt to megawatt
| gigawatt | megawatt |
|---|---|
| 0.1 | 100 |
| 0.5 | 500 |
| 1 | 1,000 |
| 2 | 2,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 100 | 100,000 |
| 250 | 250,000 |
| 500 | 500,000 |
| 1,000 | 1,000,000 |
Common values
| gigawatt | megawatt | |
|---|---|---|
| LED light bulb | 1.000000e-08 gigawatt | 0.00001 megawatt |
| Desktop computer | 3.000000e-07 gigawatt | 0.0003 megawatt |
| Microwave oven | 0.000001 gigawatt | 0.001 megawatt |
| Small car engine | 0.000075 gigawatt | 0.075 megawatt |
| Wind turbine (large) | 0.003 gigawatt | 3 megawatt |
Available Power units
More gigawatt conversions
- Convert gigawatt to watt
- Convert gigawatt to kilowatt
- Convert gigawatt to horsepower (mechanical)
- Convert gigawatt to megawatt
- Convert gigawatt to milliwatt
- Convert gigawatt to microwatt
- Convert gigawatt to BTU per hour
- Convert gigawatt to kilocalorie per hour
- Convert gigawatt to ton of refrigeration
Assumption: horsepower values use mechanical horsepower.