UNGG reactor

The UNGG (Uranium Naturel Graphite Gaz) is an obsolete nuclear power reactor design developed in France.

Of the ten units built, all were shut down by the end of 1994, most for economic reasons due to staffing costs.

It was developed independently of and parallel to the British Magnox design, both to meet similar requirements of simultaneous production of electric power and plutonium.

Although the French and the British models both used natural uranium and the same moderator and coolant, there were differences in design.

In the experimental phase they were built by the Commissariat à l'Énergie Atomique (CEA), and later by Électricité de France (EDF).