Jules Horowitz Reactor

Design and construction of the main components of the reactor block.

JHR Programme

The JHR is an experimental reactor under construction at the French Atomic Energy Commission (CEA) site in Cadarache. It will be a unique experimental irradiation tool in Europe, available to the nuclear industry and research organisations.

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The JHR, 21st century reactor, for which the CEA is the contracting authority, is:

Irradiation of materials and fuels to support the French and international nuclear industry;

The production of radio-elements for medical use.

Main services

    • Overall design of the JHR: Reactor building, experiment preparation and analysis laboratories,


    • Project management for the construction of the JHR reactor.


    • Design and manufacturing of the main components of the reactor block and the primary circuit.


  • Supplier of the reactor’s Centralised Instrumentation and Control System, and classified equipment.

© TechnicAtome


The installation of the reactor block housing in pictures

© RAZEL avec l'aimable autorisation du CEA

Latest major events:

  • Summer 2019 : Start of assembly of the reactor block and introduction of the primary heat exchangers
  • End of 2020 : Installation of the reactor block housing