The minimum geodata model defines the structure of the basic geodata of nuclear power plants. Nuclear power plants generate electricity from controlled nuclear fission on a commercial scale. The four Swiss nuclear power plants have a total capacity of 3.2 GW. Their annual availability is approximately 90%. The Swiss Federal Office of Energy (SFOE) carries out essential tasks in the enforcement of nuclear energy legislation. Safety inspections of the nuclear power plants in Switzerland are carried out by the Swiss Federal Nuclear Safety Inspectorate (ENSI), an autonomous federal institution under public law.