European Lead Fast Reactor (ELSY and LEADER projects)

The European Lead Fast Reactor is being developed starting from September 2006, in the frame of the ELSY project sponsored by the Sixth Framework Programme of EURATOM. The project, coordinated by Ansaldo Nucleare, involves a wide consortium of European organizations. The ELSY reference design is a 600 MWe pool-type reactor cooled by pure lead. The ELSY project demonstrates the possibility of designing a competitive and safe fast critical reactor using simple engineered technical features, whilst fully complying with the Generation IV goal of sustainability and minor actinide (MA) burning capability. Sustainability was a leading criterion for option selection for core design, focusing on the demonstration of the potential to be self sustaining in plutonium and to burn its own generated MAs. To this end, different core configurations have been studied and compared. Economics was a leading criterion for primary system design and plant layout. The use of a compact and simple primary circuit with the additional objective that all internal components be removable, are among the reactor features intended to assure competitive electric energy generation and long-term investment protection. Low capital cost and construction time are pursued through simplicity and compactness of the reactor building (reduced footprint and height). The reduced plant footprint is one of the benefits coming from the elimination of the Intermediate Cooling System, the low reactor building height is the result of the design approach which foresees the adoption of short-height components and two innovative DHR systems. Among the critical issues, the impact of the large mass of lead has been carefully analyzed; notwithstanding it has been demonstrated that the high density of lead can be mitigated by more compact solutions and improvement of the design of the Reactor Vessel support system, i.e. the adoption of seismic isolators for a full seismic-resistant design. Preliminary results of the reactor vessel and supports stress analysis indicate that an LFR larger than a medium-size plant (in the IAEA classification) is potentially feasible. Safety has been one of the major focus all over the ELSY development. In addition to the inherent safety advantages of lead coolant like high boiling point and no exothermic reactions with air or water, a high safety grade of the overall system has been reached. In fact overall primary system has been conceived in order to minimize pressure drops and, as a consequence, to allow decay heat removal by natural circulation. Moreover two redundant, diverse and passive operated DHR systems have been developed and adopted. The ELSY project was organised into 6 technical plus one coordination work packages. The paper presents the overall work performed so far in the different areas.JRC.F.4-Nuclear Reactor Integrity Assessment and Knowledge Managemen