Giacomo Grasso

The continuous technological evolution and the growing experience in nuclear reactors design have leaded to the formalization of new features for the next generation nuclear reactors, according to the requirements claimed by the public opinion about nuclear energy production, concerning mainly safety and sustainability. Such requirements have been interiorized in the conceptualization of the so called Generation-IV specifications:

• high economics;
• enhanced safety;
• waste minimization;
• proliferation resistance.

Coherently with the presented specifications, the Generation-IV International Forum (GIF) has identified 6 directives as candidates typologies for new reactor projects. The 6 proposed categories are:

• Gas-Cooled Fast Reactor (GFR);
• Very-High-Temperature Reactor (VHTR);
• Supercritical-Water-Cooled Reactor (SCWR);
• Sodium-Cooled Fast Reactor (SFR);
• Lead-Cooled Fast Reactor (LFR);
• Molten Salt Reactor (MSR).

Within this framework, the European commission has started a research program for the investigation of concrete solutions for each tipology of Gen-IV system. In particular, both the conceptualization and the neutronic characterization of the European Lead-cooled SYstem (ELSY), the European LFR solution, are in burden at the "E. Clementel" research center of the National Agency for the New Technologies, Energy and Environment (ENEA) in Bologna.

The fast spectrum feature has been exploited to define an "adiabatic" reactor, able to input Depleted Uranium (DU) and release Fission Products (FPs) as only wastes. A square open (wrapperless) arrangement solution has been investigated and the corresponding core conceptualized. Both deterministic and Monte Carlo calculation are in progress to adjust the core assessment for the performances tuning of the reactor.