The first discussions about the construction of the third Swiss nuclear power plant started in 1966 . In 1970 the formal request was submitted to the federal authorities . Initially foreseeing a river water cooling , the blueprints had to be modified in order to meet a new federal regulation that in 1971 forbade such systems for future plants . After the introduction of a cooling tower , the authorities issued the location authorization on 31 October 1972 . The construction started in summer 1973 , after that a series of local permits had been granted . The commissioning was authorized on 29 September 1979 . The KKG was ready to start operation in February 1979 , but the Three Mile Island accident led the Swiss Federal Council to order a security check on the Swiss plants that took some months . It eventually entered its commercial phase on 1 November 1979 . The unlimited operating license was issued on 29 September 1978
Three Mile Island accident
Three Mile Island accident
Gösgen Nuclear Power Plant