Exclusive to the UK

The Advanced Gas-cooled Reactor (AGR) is the second type of nuclear reactor to run in the nation. Since 1963, 14 AGR reactors have been built and run in the UK. AGR fuel is a type of oxide fuel made from uranium dioxide power; an AGR fuel element is made of uranium oxide pellets stacked inside stainless steel tubes. These tubes are then grouped together in a graphite sleeve to form a fuel assembly. An AGR assembly is made of 36 steel tubes, each containing 64 pellets.

How do we make AGR fuel?

  • Enriched uranium hexafluoride arrives at Springfields and is converted to uranium dioxide (UO2) powder in a kiln using a process called the Integrated Dry Route (IDR).
  • The Integrated Dry Route is a unique process we developed, which changes UF6 into a ceramic-grade uranium dioxide powder in a single stage. We do this by mixing it with steam and hydrogen in a kiln. IDR is the most environmentally friendly conversion technique now available.
  • We then process the UO2 powder again, press it, heat it on a furnace and grind it to produce the fuel pellets. The fuel pellets, which are about the size of a thimble, are stacked inside a fuel tube.
  • Once the tubes are sealed and pressurized, they are put together in the graphite “sleeve” to form the AGR fuel assembly. After it is thoroughly inspected to check the quality of the fuel, we pack it ready to send to an AGR reactor.