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ITER - from dream to reality

ITER is an enormous international scientific experiment that will provide the vital link between scientific studies of fusion plasmas and future commercial fusion power plants. It will demonstrate the scientific feasibility of fusion power, i.e. the physics required to achieve high power amplification that produces many times the amount of energy put into the experiment.


In addition, ITER will integrate the technologies essential for a fusion reactor including superconducting magnets and remote maintenance.

It will test other components such as steady-state heating systems, a first wall capable of resisting high heat loads, the divertor mechanism for removing used fuel and contaminants, and high-performance vacuum pumps to maintain low pressure in the plasma containment vessel. Although ITER will normally operate with externally supplied tritium fuel, it will also test tritium breeding module concepts for the demonstration power plant reactor.

The realisation of ITER is an unprecedented collaboration among seven parties: China, the EU (represented by Euratom), India, Japan, Russia, South Korea and the US.

Euratom has a special responsibility within the ITER Organisation as host and the major contributor to the project. The European contributions to the realisation of ITER began with site preparation at Cadarache in the south of France and the establishment of the ITER Organisation on that site and setting up of the European Joint Undertaking for ITER in Barcelona. This is now being followed by construction of infrastructure and procurement of a large proportion of the tokamak components.

R&D activities in support of ITER's construction are conducted in Fusion Associations and European industries. These activities include the development and testing of components and systems.

What will ITER look like?

ITER facilities ©ITER

ITER is a huge tokamak facility capable of generating 500 megawatts of fusion power continuously for 400 seconds or more. The plasma volume will be 10 times that of JET and will be close to the size of future commercial reactors.

ITER needs to be of such a size so as to achieve its power targets. More plasma volume means more fusion reactions and better thermal insulation for the inner hot plasma. This will increase the energy confinement time and allow scientists to study and learn to control burning plasma (plasma heated by fusion-produced hot alpha particles rather than external heating).

ITER will generate up to 10 times more power than is required to produce and heat the initial plasma with the aim of achieving a steady-state power amplification of five.

ITER essentials  
ITER tokamak diameter 24 metres
ITER tokamak height 18 metres
ITER plasma volume 850 cubic metres
ITER plasma duration 300-500 seconds
ITER plasma current 15 Mega amps