The natural development is the use of pure lead since less expensive, less corrosive and of lesser radiological concern than LBE. Lead is chemically inert and has good neutronic characteristics that are unique among the coolants for a fast reactor.

The STREP project ELSY aims at the demonstration that it is possible to design a competitive and safe fast power reactor using simple technical engineered features. Europe is taking the initiative to promote this ambitious project and it’s relevant to note that the FP6 is the last opportunity to carry out a very innovative activity with participation of young engineers and scientists, who would learn from engineers and scientists near to retirement with large experience in fast reactors design.