Grand Coulee Dam

Grand Coulee Dam is a concrete gravity dam on the Columbia River in the U.S. state of Washington, built to produce hydroelectric power and provide irrigation water. Constructed between 1933 and 1942, Grand Coulee originally had only two powerhouses. The third powerhouse, completed in 1974 to increase energy production, makes Grand Coulee the largest power station in the United States by nameplate-capacity at 6,809 MW. However, in terms of yearly power production, Grand Coulee places fifth after a number of nuclear facilities to the south, like Palo Verde west of Phoenix. This is because river flow varies throughout the year. For example, while the dam may generate at nameplate-capacity in the spring, decreased river flow in the fall means less power can be generated the rest of the year, resulting in a lower capacity factor.

https://largest-dams-2.blogspot.com/