Construction licenses were granted for the Unit 5 reactor building and the six buildings of the nuclear island

8/30/22 8:48 PM
With the issued licenses, licensing conditions for entering the second, implementation phase of the Paks II. project have been met.

The Hungarian Atomic Energy Authority issued  construction licenses on 30 August 2022 for the reactor building of Unit 5 and for six more buildings on the so-called nuclear island. After obtaining the implementation license, this is another major milestone in the life of the investment, as the license conditions for entering the second phase of the project have been fully met (the company had previously also obtained the manufacturing licenses for core catchers and reactor pressure vessels).


The reactor building is the main building of the Unit and is intended to house the reactor pressure vessel, the main water circuit, the steam generators, the spent fuel pool and the cooling systems for malfunction, as well as the service, auxiliary and control systems. The task of the reactor building with the special double-walled containment design is to ensure that the environment is not adversely affected during nuclear energy production, but its massive design also ensures the protection of technological systems against environmental or man-made hazards. 

The external containment with a diameter of 52,4 meters has a reinforced concrete structure, and its height is 72 m. The inner containment is a cylindrical building with an internal diameter of 44 m, which is topped by a dome. The thickness of the inner containment wall is 1,2 m in the cylindrical part. The walls of the inner containment, made of prestressed reinforced concrete, are covered from the inside with a 6 mm thick carbon steel covering, which ensures the hermetic isolation of the inner space of the containment from the environment.


On the same day, another six buildings around the reactor building, which make up the unit's so-called „nuclear island”, received construction licenses. The service and auxiliary systems of the main technological process of nuclear energy production located in the reactor building, as well as the systems and controllers that ensure the control and safety supervision of the operation, are located in these buildings.

The six buildings:

  • Control building
  • Auxiliary building
  • Steam cell
  • Safety building
  • Switching chamber
  • Equipment lock tresle

The buildings have received a safety and earthquake protection classification based on the safety functions of the technology systems in them, and their design accordingly ensures the protection of workers and the environment from the effects of radiation, as well as the protection of their technology systems against environmental and man-made hazards.