Challenges for cryogenics in the nuclear fusion quest. The ITER cryogenic system

ITER, designed to demonstrate the scientific and technical feasibility of nuclear fusion as a primary source of virtually inexhaustible energy, has entered the construction phase at Cadarache, South of France. This world largest superconducting fusion reactor will enter operation in 2020 and full nuclear phase in 2027. Cryogenic technology is extensively employed to achieve low-temperature conditions for the magnet and vacuum pumping systems. After describing the basic features of ITER and its cryogenic system, we shall present the key design requirements and challenges to build an economically viable cryogenic system operating in a nuclear environment. (author)