The Johnsonville Steam Plant is the second steam-electric project to be built by TVA. The first-Watts Bar Steam Plant-was built as a part of TVA's first emergency program of the World War II period. Construction of the Johnsonville Steam Plant, with generating units of 125,000-kilowatt capability, began in May 1949. It was the first of seven large steam-electric projects constructed over a span of eight and a half years including the Korean War period. This mammoth building program resulted mainly from the increased power demands of the Atomic Energy Commission and other Federal defense agencies. Additional electric energy was required also by the expanding programs of private industry and the increased needs of commercial and domestic consumers in TVA's service area.

Kingston Steam Plant is located at the base of a peninsula formed by the Clinch and Emory River embayments of Watts Bar Lake about 2.7 miles above the confluence of the Clinch and Tennessee Rivers. The plant derives its name from Kingston, a small town of colorful history lying two miles to the south, which employs the distinction of being the capital of the State of Tennessee for one day, September 21, 1807.