Megawatt (MW)

A megawatt measures power: how fast a plant can produce electricity at a given moment. One megawatt is 1,000 kilowatts.

Also called MW

Formula

Energy (MWh) = power (MW) × hours

With real numbersGrand Coulee at full output for a year: 6,809 MW × 8,760 h = 59.6 TWh. It made 16.2 TWh in 2025.

6,809 MWGrand Coulee, the largest US power plant by nameplate capacity

Grand Coulee can deliver 6.8 GW at full output. That is a rate, like speed. How much energy it made depends on how many hours it ran that hard.

Nameplate capacity, MW

EIA-860M nameplate capacity and EIA-923 net generation, 2025.On the map

Built from InfraMap's 2025 data with the same tools the analyst uses.

Using MW as an amount of electricity. A 100 MW plant produces up to 100 MWh in each hour it runs at full power, not 100 MW a year.
Multiplying nameplate MW by 8,760 hours and calling it output. That is the ceiling. Real output depends on how many hours the plant actually runs, which is its capacity factor.
Mixing AC and DC ratings. Solar panels are rated in DC, and the grid sees the lower AC rating of the inverters.

The rate of energy production or use. MW is not an energy total. Integrate power over elapsed time for MWh.

Energy MWh = sum of average interval MW times elapsed interval hours

Reviewed October 1, 2026 against the references below. The analyst and the MCP server answer with this definition.

EIA measuring electricityeia.gov · Power and energy units
EIA capacity and generationeia.gov · Nameplate, seasonal capacity and capacity factor