Planning for the KKL began in 1964 for a 600 MW reactor . The Swiss Federal Council opposed direct cooling by river water , replaced in the design in 1971 with a cooling tower . During further planning the output was increased to 600 and then 900 MW . In the wake of the 1979 Three Mile Island accident new safety regulations were implemented , delaying completion for several years . The 2 billion Swiss franc construction budget spiraled to over 5 billion before the plant opened in 1984 after eleven years of construction
Three Mile Island accident
Three Mile Island accident
Leibstadt Nuclear Power Plant