The group, which consists mainly of public nuclear research agencies, selected the following six systems on which to focus its research efforts.
SODIUM-COOLED FAST REACTOR (SFR)
* Using superheated liquid sodium as a coolant, this is the most mature technology of the six.
* The metal's low melting point and high boiling point allow the reactor to operate at near-atmospheric pressure.
* Sodium explodes in water and catches fire in air, so research is focused on making the reactors leak-proof.
* Prototypes have been tested in France, Russia and Japan, with China, South Korea and India also proceeding with SFR projects.
LEAD-COOLED FAST REACTOR (LFR)
* Can operate at atmospheric pressure and high temperatures because of lead's high boiling point of 1,750 degrees Celsius.
* The lead must be kept hot at all times to prevent it from solidifying.