Introduction
In 2011 it was planned the spanish participation in the international initiative ESNII promoted by the european platform SNETP. This european initiative is aimed at the construction of prototypes or demonstrators of technologies such as SFR (ASTRID prototype), LFR (MYRRHA prototype and ALFRED demonstrator), and GFR (demonstrator ALLEGRO), within an horizon between 2022 to 2025 for start-up.
