The data concerning the present nuclear power installations in Switzerland are taken from [1]. For the year 2012, the capacity factor of nuclear power plants has been 84.9% [2], which is assumed to be the capacity factor of power plants in the future. For the efficiency and therefore the fuel consumption, a value of 33% (thermal efficiency) is assumed in line with IEA guidelines [3]. The energy production is assumed to be constant for the different months, and the maximum potential is assumed to be the coverage of overall Swiss electricity needs.
[1] World Nuclear Association - Nuclear power in Switzerland
[2] SFOE Swiss Federal Office of Energy - Electricity Statistics