The world's greatest tokamak, the International Thermonuclear Experimental Reactor ITER, is being built in Cadarache, France. It is supposed to generate 500 MW and release ten times more energy than will be needed for plasma heating and confinement. The ITER is a joint project of China, the EU, India, Japan, Korea, Russia, and the USA. The device has a plasma volume of 840 m³ and toroidal magnetic coils 17 meters high.

Forty-four openings, or ports, in the vacuum vessel provide access for remote handling operations, diagnostics, heating, and vacuum systems. For example, neutral beam injection will take place at equatorial level, on the lower level, five ports will be used for divertor cassette replacement and four for vacuum pumping.

The largest thermos ever built. This enormous stainless steel high-vacuum pressure chamber (16,000 m³) provides the high vacuum, ultra-cool environment for the ITER vacuum vessel and the superconducting magnets. The high vacuum is maintained by a system of vacuum pumps. The cryostat will have about 280 penetrations which will provide access for piping, electricity, heating systems, diagnostics and remote handling systems. Each one of these openings will have to be as leak-tight as possible to preserve the cryostat's vacuum environment.

Magnet feeders provide a necessary supply of electric current and coolant to superconducting magnets. In order to do so, they are cross warm-cold barrier from room-temperature to the low-temperature of superconducting coils 4 K (-269°C). They are equipped with independent cryostats and thermal shields and include the high-temperature superconductor current leads, cryogenic valves, superconducting busbars, and high-voltage instrumentation hardware.

A cylindrical concrete pit around tokamak with walls up to 3.2 meters thick.

Neutral Beam Injection is actually a particle accelerator that accelerates deuterium ions with an electric field. To keep them from being affected by the magnetic field, the particles are neutralized before entering the plasma and then transfer their energy to the plasma by collisions. The ITER will be equipped with two heating neutral beam injectors. Each one will deliver a deuterium beam of 16.5 MW with particle energies of 1 MeV.

Resonance heating works much like a microwave oven. Radio waves of the right frequency transfer energy to the particles in the plasma and heat them up. The particles then transfer energy to each other by collisions. The Ion Cyclotron Resonance Heating will use a frequency of 40 to 55 MHz to heat the ions. Two transmitting antennas will be about 3.5 metres long, with a cross section of 2 × 2 metres and a weight of nearly 50 tonnes. The system will deliver 20 MW of energy to about 1 gram of plasma thus raising its temperature very high and very quickly.

Resonance heating works much like a microwave oven. Radio waves of the right frequency transfer energy to the particles in the plasma and heat them up. The particles then transfer energy to each other by collisions. Electron Cyclotron Resonance Heating will heat electrons using a frequency of 170 GHz and supply an additional 20 MW of energy to the plasma. Radio waves for radiofrequency heating are produced by gyrotrons in the Radiofrequency Building and fed into ITER via waveguides.

Tokamak ITER will be assembled and operated in this building.

The diagnostics building will house electronic and information systems that will receive record and interpret signals from diagnostics placed inside the ITER tokamak. This part of data collection system needs to be shielded from the nuclear and thermal loads to work properly. Data will be then sent to a Control room to tokamak operators.

Fusion reactions in the ITER will be fueled by hydrogen isotopes deuterium and tritium. While deuterium is an easy-to-handle stable element, rare and radioactive tritium must be handled with extreme care. The whole Tritium building will accommodate the different systems and equipment that store, handle and recycle tritium. Also tokamak's cooling water systems, fuel injection equipment, pumping etc. will be situated there.

1,500-tonne double overhead bridge crane.

The largest thermos ever built. This enormous stainless steel high-vacuum pressure chamber (16,000 m³) provides the high vacuum, ultra-cool environment for the ITER vacuum vessel and the superconducting magnets. The high vacuum is maintained by a system of vacuum pumps. The cryostat will have about 280 penetrations which will provide access for piping, electricity, heating systems, diagnostics and remote handling systems. Each one of these openings will have to be as leak-tight as possible to preserve the cryostat's vacuum environment.

A shield block is mounted on the inner wall of the vacuum vessel and provides nuclear shielding as well as support for the first wall panels. Cooling water runs through the shield blocks to remove the high heat load from fusion reactions.

The detachable, front-facing element of the blanket that is designed to withstand the heat flux from the plasma is made of beryllium tiles bonded with a copper alloy and stainless steel.

The inner walls of the vacuum vessel are covered with 440 blanket modules that protect the vessel and superconducting toroidal field magnets from the heat and high-energy neutrons produced by the fusion reactions. Modules are composed of detachable plasma-facing first wall and a main shield block that is designed for neutron shielding. Cooling water flows through the shielding block removing heat load. The ITER will be the first fusion device to operate with an actively cooled blanket.

Forty-four openings, or ports, in the vacuum vessel provide access for remote handling operations, diagnostics, heating, and vacuum systems. For example, neutral beam injection will take place at an equatorial level, on the lower level; five ports will be used for divertor cassette replacement and four for vacuum pumping.

A doughnut-shaped steel container (torus) where the fusion reactions take place. The vessel provides a high-vacuum environment for the plasma and acts as the primary confinement barrier for radioactivity. It is also a support structure for in-vessel components like the divertor or blanket. Excessive heat generated during fusion reactions will be removed by cooling water circulating through the vessel's double walls. Inside the double walls is also neutron in-wall shielding made from borated and ferromagnetic stainless steel. The interior volume of the vacuum vessel is 1,400 m³.

A set of 27 non-superconducting coils fixed to the wall of the vessel creates resonant magnetic perturbations in the plasma so that certain types of plasma instabilities, called Edge-Localized Modes (ELMs), are avoided.

Two poloidal non-superconducting coils installed above and below the machine's mid-plane provide fast vertical stabilization of the plasma.

A system of non-superconducting coils, manufactured from a special type of mineral-insulated copper conductor, located inside the ITER vacuum vessel, provides additional plasma control capabilities. Two vertical stability coils provide fast vertical stabilization of the plasma.

Magnet feeders provide a necessary supply of electric current and coolant to superconducting magnets. In order to do so, they cross warm-cold barrier from room-temperature to the low-temperature of superconducting coils 4K (-269 °C). They are equipped with independent cryostats and thermal shields and include the high-temperature superconductor current leads, cryogenic valves, superconducting busbars, and high-voltage instrumentation hardware.

Smaller superconducting coils placed between the toroidal and poloidal field coils will compensate magnetic field errors. Eighteen coils are arranged in groups of six around the toroidal circumference above, at and below the mid-plane of the vacuum vessel.

The independently operating coil packs of the central solenoid will create huge electromagnetic forces that pull in different directions. Therefore the solenoid is packed within a strong pre-compression support structure that will keep its structural integrity. The supportive 'cage' made from superaustenitic stainless steel - tie plates running the full height of the central solenoid assembly (both externally and internally) holds its six coils together. The structure will have to withstand roughly 180 MN to resist coil separation during operation.

Part of the central solenoid support structure actively keeps its position right in the center of the vacuum vessel.

A central solenoid will induce a strong current in the ITER plasma and maintain it during long pulses. A solenoid is 13 m (or 18 m with a support structure) tall and consists of six independent coil packs wound from niobium-tin (Nb₃Sn) superconducting cable.

Six ring-shaped poloidal field coils made from niobium-titanium (Nb-Ti) superconductors are situated outside of the toroidal field magnet structure to shape the plasma and contribute to its stability by 'pinching' it away from the walls. The largest coil has a diameter of 24 meters; the heaviest is 400 tons.

Toroidal field magnets are in the shape of a giant 'D' and are placed around the vacuum vessel. The purpose of their magnetic field is mostly to confine the plasma particles. Manufactured from niobium-tin (Nb₃Sn), the magnets become superconducting when cooled with supercritical helium in the range of 4 Kelvin (-269 °C). They are composed of layers of spiraled conductors embedded in radial plates enclosed in a stainless steel structure. Each weights 360 tons and is 17 m high.

A device situated at the bottom of the tokamak vessel. The divertor extracts heat and ash produced by the fusion reaction to minimize plasma contamination, and protects the surrounding walls from thermal and neutronic loads. A large amount of diagnostics placed inside the divertor helps to monitor and control the plasma. The ITER divertor is composed of 54 'cassette assemblies'.

The bottom part of the divertor leading toward the plasma is made of wolfram and shaped so that it surface follows the magnetic field lines under the crossing at the zero point. The main function of the central dome is to protect other parts of the divertor during the creation or abnormal motion of plasma.

Plasma-facing components of the divertor are made from tungsten and are positioned at the intersection of magnetic field lines where particle bombardment will be particularly intense in the ITER. The heat load will be ten times higher than a spacecraft re-entering Earth's atmosphere experiences. Heat is removed by active water cooling.

The divertor's supporting structure is made of stainless steel.

Output of the tokamak’s water cooling system. Water will flow through pipes at a rate of 5 m³/second and remove heat from the vacuum vessel, blanket or divertor.