FAQ
What is the largest power station in the world?
The Three Gorges Dam in China, at 22,500 MW. It has held the record since 2012 and generated a record 112 TWh in 2020, roughly the yearly electricity use of a mid sized country.
What is the largest power plant in the United States?
By capacity, Grand Coulee Dam at about 6,800 MW. By yearly electricity generated, the Palo Verde nuclear station in Arizona usually leads, because nuclear plants run nearly flat out all year.
What is the difference between MW and MWh?
A megawatt is instantaneous power, like the speedometer of a car. A megawatt hour is energy delivered over time, like the odometer. A 100 MW plant running for 10 hours delivers 1,000 MWh.
What is a capacity factor?
Actual energy produced divided by the maximum possible if the plant ran at full power every hour of the year. US nuclear plants average about 92 percent, hydro 30 to 50, wind about 35, and solar 15 to 25 percent.
What is pumped storage?
A water battery. Cheap power pumps water uphill to a reservoir, then releases it through turbines when demand and prices peak. Round trip efficiency is 70 to 80 percent. Bath County in Virginia, 3,003 MW, is among the largest in the world.
Which power source has the lowest carbon emissions?
Wind, nuclear and solar all deliver lifecycle emissions of roughly 5 to 50 grams of CO2 per kWh, an order of magnitude below gas and about 30 times below coal. Hydro varies with reservoir conditions but is usually low.