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 microwatt?

A microwatt is a unit of power equal to one millionth of a watt. It is used in ultra-low-power electronics, energy harvesting systems, biosensors, and precision scientific instrumentation.

Real-world uses

Microwatts measure the power of radio frequency (RF) signals received by antennas, ultra-low-power IoT sensors, cardiac pacemaker power consumption, and energy-harvesting devices. Satellite receivers may work with signals in the nanowatt to microwatt range. Wearable health monitors often operate at a few microwatts.

History

Microwatts became a meaningful engineering unit as semiconductor miniaturisation through the 1970s–2000s enabled ultra-low-power circuit design. The proliferation of wireless sensors, implantable medical devices, and battery-free energy harvesting systems in the early 21st century made µW-level power budgeting essential.

Common mistakes

Confusing microwatts (µW) with milliwatts (mW)—a difference of 1,000×. In RF engineering, power is often expressed in dBm (decibels relative to 1 mW), which requires knowing that 0 dBm = 1 mW = 1,000 µW, and negative dBm values correspond to sub-milliwatt levels.

When is this conversion used?

Converting gigawatt to microwatt 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 = 1.000000e+15 microwatt

1 microwatt = 0.000001 watt

How to convert gigawatt to microwatt

To convert gigawatt to microwatt, multiply the value by 1.000000e+15.

To convert microwatt back to gigawatt, multiply by 1.000000e-15.

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 microwatt

gigawattmicrowatt
0.11.000000e+14
0.55.000000e+14
11.000000e+15
22.000000e+15
55.000000e+15
101.000000e+16
252.500000e+16
505.000000e+16
1001.000000e+17
2502.500000e+17
5005.000000e+17
1,0001.000000e+18

Common values

gigawattmicrowatt
LED light bulb1.000000e-08 gigawatt10,000,000 microwatt
Desktop computer3.000000e-07 gigawatt300,000,000 microwatt
Microwave oven0.000001 gigawatt1.000000e+09 microwatt
Small car engine0.000075 gigawatt7.500000e+10 microwatt
Wind turbine (large)0.003 gigawatt3.000000e+12 microwatt