The WEST, or
Tungsten
Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first ...
(
chemical symbol
Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist ...
"W") Environment in Steady-state Tokamak, (formerly Tore Supra) is a French
tokamak
A tokamak (; ) is a device which uses a powerful magnetic field generated by external magnets to confine plasma (physics), plasma in the shape of an axially symmetrical torus. The tokamak is one of several types of magnetic confinement fusi ...
that originally began operating as Tore Supra after the discontinuation of
TFR (Tokamak of
Fontenay-aux-Roses) and of Petula (in
Grenoble
Grenoble ( ; ; or ; or ) is the Prefectures in France, prefecture and List of communes in France with over 20,000 inhabitants, largest city of the Isère Departments of France, department in the Auvergne-Rhône-Alpes Regions of France, region ...
). The original name came from the words
torus
In geometry, a torus (: tori or toruses) is a surface of revolution generated by revolving a circle in three-dimensional space one full revolution about an axis that is coplanarity, coplanar with the circle. The main types of toruses inclu ...
and
superconductor, as ''Tore Supra'' was for a long time the only tokamak of this size with
superconducting
Superconductivity is a set of physical properties observed in superconductors: materials where electrical resistance vanishes and magnetic fields are expelled from the material. Unlike an ordinary metallic conductor, whose resistance decreases g ...
toroidal magnets, allowing the creation of a strong permanent toroidal
magnetic field
A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...
. After a major upgrade to install tungsten walls and a divertor, the tokamak was renamed WEST (the name alludes to
EAST
East is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth.
Etymology
As in other languages, the word is formed from the fact that ea ...
, another tokamak).
WEST is situated at the nuclear research center of
Cadarache
Cadarache () in Southern France is the largest technological research and development centre for energy in Europe. It includes French Alternative Energies and Atomic Energy Commission, CEA research activities and ITER. CEA Cadarache is one of th ...
,
Bouches-du-Rhône
Bouches-du-Rhône ( ; , ; ; "the Mouths of the Rhône") is a Departments of France, department in southern France. It borders Vaucluse to the north, Gard to the west and Var (department), Var to the east. The Mediterranean Sea lies to the sout ...
in
Provence
Provence is a geographical region and historical province of southeastern France, which stretches from the left bank of the lower Rhône to the west to the France–Italy border, Italian border to the east; it is bordered by the Mediterrane ...
, one of the sites of the
Commissariat à l'Énergie Atomique
The French Alternative Energies and Atomic Energy Commission, or CEA ( French: Commissariat à l'énergie atomique et aux énergies alternatives), is a French public government-funded research organisation in the areas of energy, defense and sec ...
. Tore Supra operated between 1988 and 2010. Its goal was to create long-duration plasmas. The upgrade to WEST took place between 2013 and 2016. WEST has been operating since 2016.
Tore Supra long held the record for the longest plasma duration time for a tokamak, at 6 minutes 30 seconds.
[ With over 1000 MJ of energy injected and extracted in 2003, and it allowed researchers to test critical parts of equipment such as plasma facing wall components or superconducting magnets that will be used in its successor, ]ITER
ITER (initially the International Thermonuclear Experimental Reactor, ''iter'' meaning "the way" or "the path" in Latin) is an international nuclear fusion research and engineering megaproject aimed at creating energy through a fusion process s ...
. As ITER faced long delays, WEST remained in operation and on 12 February 2025, it set a new record for duration at 22 minutes and 17 seconds, while operating at lower temperatures.
Device parameters
Tore Supra as of 1988:
* Major plasma radius (machine centre to plasma centre) : 2.25 m
* Minor plasma radius: 0.70 m
* Toroidal magnetic field on the center of the plasma core: 4.5 T
* Plasma current: 1.7 MA
* Longest plasma discharge (predicted): 1000 s
* Auxiliary plasma heating (ion
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...
and electron cyclotron resonance heating and lower hybrid current drive): 20 MW
Tore Supra as of 2006 (parameters essentially the same):[THE TORE SUPRA TOKAMAK]
/ref>
* Weight of NbTi superconductor : ~45 tonnes
* Maximum magnetic field on the conductor : 9.0 T
* Total magnetic energy : 600 MJ
* Weight of magnetic circuit : 830 tonnes
WEST as of 2018:
* Major plasma radius (machine centre to plasma centre) : 2.5 m
* Minor plasma radius: 0.50 m
* Toroidal magnetic field on the center of the plasma core: 3.7 T
* Plasma current: 1 MA
* Longest plasma discharge (predicted): 1000 s
* Auxiliary plasma heating (ion
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...
and electron cyclotron resonance heating and lower hybrid current drive): 17 MW
Tore Supra Operation 1988–2010
By 1998 it had produced over 20,000 plasma shots of up to 2 minutes duration.[Tore Supra, description, results.]
Select 6. main/major results
Between 2000 and 2002 the vacuum chamber was completely renewed/relined. increasing the power extraction by active cooling to 25 MW (to allow longer plasma duration).
Select 4. Extracting power
In December 2003, it achieved a record 6.5 minute plasma[6.5-minute pulse in Tore Supra. Dec 2003]
/ref> This was plasma shot #32299, Lower hybrid power ~2.9 MW, total injected energy ~1.1 GJ, plasma current ~500 kA, nl ~ 2.6x1019 m−2.[
]
WEST
Beginning in March 2013 Tore Supra underwent an extensive refit, including new poloidal coils to achieve diverted operation, a new cooling system, and all-metal cladding, mainly for experiments on tungsten
Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first ...
divertor
In magnetic confinement fusion, a divertor is a magnetic field configuration which diverts the heat and particles escaped from the magnetically confined plasma to dedicated plasma-facing components, thus spatially separating the region plasma ...
technology for ITER
ITER (initially the International Thermonuclear Experimental Reactor, ''iter'' meaning "the way" or "the path" in Latin) is an international nuclear fusion research and engineering megaproject aimed at creating energy through a fusion process s ...
.
The reactor was renamed WEST, for "Tungsten (chemical symbol
Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist ...
"W") Environment in Steady-state Tokamak". WEST achieved first plasma in December 2016. WEST was able to maintain a plasma for 1,337 seconds on February 12, 2025.
References
External links
Tore Supra Official Site
EURATOM– CEA (in French)
Tore Supra Official Site – in English
{{fusion experiments
Tokamaks
Laboratories in France