Huge-scale cryogenics: ITER

The ITER fusion project is the world's largest, international effort at developing an energy-positive experimental fusion reactor involving the People's Republic of China, the European Union and Switzerland, Japan, the Republic of Korea, the Russian Federation, the USA and India. It is based on a hydrogen plasma torus (Tokamak) operating at over 100 million °C and will produce 500 MW of fusion power. Construction will take place in Cadarache, France as of 2008. The ITER Plant is approximately 1 kilometre long. The cryogenic system is divided into three parts: the cryoplant, the cryodistribution system and the system of cryogenic lines and manifolds. It contains a liquid helium (LHe) plant with a 43 kW of refrigeration capacity plus 0.17 kg/s of liquefaction for cool-down of the magnets and the cryopumps during their regeneration. An 80 K He loop, together with a liquid nitrogen (LN2) pre-cooling stage is used for the active cooling of the 80 K thermal shields inside the cryostat. A cryodistribution system consisting of long and complicated cryogenic transfer lines and manifolds incorporating several cold boxes with cold compressors or cold circulating pumps provides forced flow cooling of the magnet system and cryopumps.