Tritium breeder blankets design and technologies in Europe: Development status of ITER Test Blanket Modules, test & qualification strategy and roadmap towards DEMO

Abstract Europe has developed two reference tritium breeder blankets concepts that will be tested in ITER under the form of Test Blanket Modules: (i) the Helium-Cooled Lithium–Lead which uses the liquid Pb–15.7Li as both breeder and neutron multiplier, (ii) the Helium-Cooled Pebble-Bed with lithiated ceramic pebbles as breeder and beryllium pebbles as neutron multiplier. An extensive development program has been carried-out over the last decade combining experimental and numerical simulations aimed at identifying and quantifying physical phenomena occurring in breeder blankets and at optimizing their design and technologies accordingly. On this basis, sound guidelines for the design and technological choices of Test Blanket Modules can be derived. In addition, regulatory and ITER project requirements, which prefigure the future DEMO blanket ones, are now integrated in the development and qualification program of the Test Blanket Modules. Their scope and implication are analyzed.