WEST (WESTPAS)

WEST (WESTPAS)
Name	WEST (WESTPAS)
Type	Plasma-facing tokamak testbed
Established	2016 (conversion)
Location	Cadarache, France
Operator	CEA
Affiliation	ITER Organization, Euratom
Reactors	ITER-relevant tokamak
Status	Operational

WEST (WESTPAS)

WEST (WESTPAS) is a French tokamak research facility repurposed to test tungsten divertor technologies for long-pulse, high-power fusion scenarios. Located at Cadarache, it provides a platform linking experimental results to projects such as ITER, DEMO and other European efforts under Euratom. WEST bridges material science, plasma physics, and engineering communities including CEA researchers, international partners from JET teams, and industrial collaborators like Air Liquide and Assystem.

Overview

WEST operates as a fully metallic, tungsten-armored tokamak emphasizing diverted plasmas and long-duration pulses to evaluate plasma–wall interactions relevant to ITER and DEMO. The facility integrates diagnostics developed by institutes such as Max Planck Institute for Plasma Physics teams, experimental campaigns coordinated with JET and theoretical inputs from Princeton Plasma Physics Laboratory scientists. WEST contributes to cross-cutting initiatives involving European Space Agency interest in materials performance and collaborations with ENEA and KIT.

History and Development

The machine originated from the former Tore Supra tokamak, which was rebuilt and recommissioned to address tungsten divertor challenges encountered in devices like ASDEX Upgrade and JET. The conversion project involved international partnerships including ITER Organization advisors and contractual support from firms such as Areva subsidiaries. Initial design studies referenced operational lessons from DIII-D and legacy experiments at TEXTOR and built on tungsten research at JET and ASDEX Upgrade. WEST achieved first plasma after conversion and entered phased experimental campaigns aligned with European roadmaps toward DEMO milestones.

Technology and Design

WEST features a fully metallic first wall and actively cooled tungsten divertor components designed to withstand high heat fluxes informed by ITER requirements. The tokamak retains superconducting magnet lessons from Tore Supra heritage while incorporating power systems and neutral beam concepts analogous to JT-60SA and radiofrequency systems comparable to EAST. Diagnostics include infrared thermography, spectroscopy packages developed with CNR partners, and Thomson scattering reminiscent of systems used at TCV. Engineering choices reflect input from industrial partners such as Framatome and standards referenced to ASN guidance.

Operations and Deployment

Operational campaigns are planned to simulate steady-state and long-pulse scenarios with durations drawing on experience from Tore Supra and continuous operation concepts from EAST. WEST scheduling coordinates with ITER experiment timelines and European roadmap programs run by Euratom and national agencies like CNRS and CEA. Deployment of diagnostic suites and material test modules has been staged to allow comparative studies with JET campaigns and to provide validation data for modelling groups at Princeton Plasma Physics Laboratory and Max Planck Institute for Plasma Physics.

Safety and Regulatory Compliance

Safety and compliance for WEST follow national regulators such as ASN and national legislation interfaces through CEA oversight. Design reviews paralleled practices used in ITER licensing studies and incorporated lessons from regulatory interactions involving JRC analyses. Radiological controls, cryogenics safeguards, and high-voltage infrastructure adhere to standards shared with projects like SPIRAL2 and industrial nuclear facilities managed by EDF-related entities.

Performance and Environmental Impact

Performance metrics target tungsten erosion rates, helium ash handling, and impurity transport under conditions analogous to ITER divertor loads and DEMO-relevant duty cycles. Environmental impact assessments considered water cooling, tritium management strategies informed by JET tritium campaigns, and waste streams analogous to those characterized at CEA laboratories. WEST supports modelling efforts by groups at Oxford University and MIT to predict lifetime and disposal pathways consistent with European decommissioning frameworks used in projects like Superphénix.

Notable Projects and Case Studies

Notable campaigns include comparative tungsten sputtering studies coordinated with JET and material exposure tests referencing results from ASDEX Upgrade and TEXTOR. Collaborative experiments with Princeton Plasma Physics Laboratory focussed on transport phenomena, while diagnostic benchmarking involved teams from Max Planck Institute for Plasma Physics and EAST. Case studies published by CEA teams drew on cross-validation with JT-60SA modelling and industrial heat-flux testing performed with partners such as Framatome and Air Liquide to inform ITER divertor design choices.

Category:Tokamaks Category:Fusion power in France