Pressure and levels? Nominal. Valves? Open. Protections? In place. As all “permissives” are go , the process can now be activated. A click of a mouse and—in a building more than half a kilometre away—a powerful pump kicks in and water starts rushing into one of the cooling loops of the reactive power compensation installation. On Thursday 19 December, during an event that brought together a few dozen ITER and Fusion for Energy (European Domestic agency) staff along with contractors, the ITER main control room issued its first CODAC (Control, Data Access and Communication) command to a plant system, a decisive milestone towards tokamak operation. Across the ITER platform, several temporary control rooms, each dedicated to one plant system, are already operational. In the coming year, they will progressively be folded into the main control room, an approximately 750-square-metre space on the first floor of the Control Building.For the moment, only one desk is occupied and three screens are lit. When full science operation starts, the room will be home to some 80 operators, engineers and researchers monitoring millions of plasma, tokamak and plant system parameters in real-time. Raising their eyes from their computer screens, they will be able to read a 120-square-metre mosaic of screens displaying the installation’s overall status. Spectacular…“This room will be seen around the world. It was built to realize fusion energy and this is where it will happen,” said Tim Luce, former Chief Scientist for ITER, now Deputy Head of the Construction Project. Seven years have elapsed since the first “pencil and paper” drawings of the room and building, “seven years to get to the end of the beginning,” mused Luce. The construction of the Control Building, under Europe’s responsibility, was an exercise in “collaborative intelligence, openness and pragmatism,” added Romaric Darbour, Fusion for Energy deputy head of the Buildings and Site Management Programme.  More than 16 years ago, Anders Wallander (speaking) joined ITER to implement the CODAC system. From left to right: Deputy Head of ITER Construction Project Tim Luce; Fusion for Energy deputy head of the Buildings and Site Management Programme Romaric Darbour, and ITER Director-General Pietro Barabaschi. An important milestone for all, the first CODAC command issued from the main control room carried a special and personal significance for one of the people present: more than 16 years ago, Anders Wallander, fresh from a two-decade stint with the European Southern Observatory (ESO) in Munich and the Chilean Andes, joined ITER to implement the Control, Data Access and Communication system—“a system of systems” designed to play conductor to ITER operation. All instruments are not playing yet, but one million “process variables,” out of a total of 5 million, are already online. Anders’ journey from the stars in heaven to the future star in the machine is nearing completion.In March, the European Domestic Agency Fusion for Energy plans to hand the Control Building over to the ITER Organization.Click here to view a short video of the event. 

An international consortium is working together to deliver a high-performance diagnostic system essential for ITER’s mission—the high-resolution neutron spectrometer. On 5-6 December 2024, the consortium developing ITER's high-resolution neutron spectrometer (HRNS) met at Uppsala University in Sweden to review the project's progress. The HRNS, a state-of-the-art neutron diagnostic, is being developed through a collaborative effort between the ITER Organization, Uppsala University and Fagerström (Sweden), the Institute of Nuclear Physics (IFJ-PAN, Poland), and the National Research Council of Italy (CNR).The meeting marked a key moment in the project as the team assessed the current status of HRNS development and laid the groundwork for the upcoming preliminary design reviews. Once operational, the HRNS will play a critical role in ITER, providing high-precision measurements of neutron spectra to support plasma performance and fusion research.The HRNS system is composed of four distinct spectrometers: the thin-foil proton recoil (TPR) spectrometer, the neutron diamond detector (NDD) spectrometer, and the forward and backward time-of-flight (TOF) spectrometers. Each spectrometer utilizes a unique measurement principle, delivering independent yet complementary measurements. Together, these spectrometers cover the full dynamic range of ITER’s nuclear operations, providing a comprehensive and robust diagnostic for fusion research.The project is co-funded by the ITER Organization, the Swedish Energy Agency, the Polish Ministry of Education and Science under the International Co-financed Projects program, and the Italian National Research Council. This partnership reflects the international collaboration at the heart of ITER, bringing together expertise and resources from across the globe to advance fusion diagnostic technologies. "The HRNS project exemplifies what can be achieved when organizations from different countries combine their knowledge and efforts,” says Bruno Coriton, HRNS Project Coordinator at ITER. “This diagnostic system will be instrumental to ITER’s goals of achieving high-power fusion energy.”Max Collins, Swedish Industrial Liaison Officer for ITER and Fusion for Energy, emphasized the broader impact of the project. "The engagement of Swedish companies and research groups in Big Science projects like ITER is crucial for driving innovation and boosting the competitiveness of Sweden. This collaboration not only enhances their capabilities in cutting-edge fusion technology but also raises awareness of ITER and of the transformative potential of fusion energy in Sweden."At this stage of the HRNS project, scientific research and advanced technology implementations are closely intertwined. Hence, a close collaboration between academic research, high-tech industry and the ITER Organization has been established. According to Anders Hjalmarsson, Lead Scientist at Uppsala University, “this cooperation is a necessity to achieve a successful outcome in the challenging task of developing and interfacing a HRNS system at ITER.”Looking ahead, the consortium is focused on meeting key design milestones and ensuring the HRNS aligns with ITER’s demanding technical and operational requirements. As preparations for the preliminary design reviews move forward, the project is on track to deliver a high-performance diagnostic system essential for ITER’s mission.

Working on site during the annual office closure period is certainly not everyone's idea of an end-of-year holiday...  And yet a not-so-small team of ITER staff volunteered to keep the wheels running and to keep pushing forward with the assembly of the ITER tokamak. On their list of tasks to advance in collaboration with contractors:  installing the vacuum vessel thermal shield on sector #6, machining the intercoil structure for sector module #7, and the start of on-the-ground preparations for the assembly of sector module #5. The teams also began reinstalling repaired panels of the support thermal shield in the pit. These panels provide a thermal barrier between the toroidal field coil gravity supports and the vacuum vessel, and they must be positioned before vacuum vessel sector module #7 is lowered into the pit later this year (April).See the Construction Gallery for a selection of photos.

On 19 December 2024, one year almost to the day after it was delivered, a fourth module was installed on top of the existing central solenoid stack. Standing on its bespoke platform, the massive, tower-like structure being assembled in the ITER Assembly Hall (left) now reaches approximately two-thirds of its final height. Procured by the United States, the central solenoid modules (6 plus one spare) are manufactured by General Atomics near San Diego. Two more modules need to be stacked and connected to finalize the assembly of the 1,000-tonne superconducting magnet whose role is to induce and sustain a powerful current (15 MA) inside the plasma.Handling the 2-metre-tall, 110-tonne cylindrical component is a particularly delicate task. Contrary to the vast majority of ITER machine components, which are lifted by way of hooks and attachments, a central solenoid module requires nine powerful wedge pads located at the bottom of a lifting fixture (right), each one exerting a radial force of 220 kN (equivalent to 22 tonne-force) on nine friction pads distributed around the cylinder—a bit like grasping a giant bowl of cereal by exerting pressure from the outside. 

Many of the components that make up the ITER device require sub-millimetre accuracy for assembly—a feat accomplished with specialized metrology equipment that is calibrated at regular intervals. The ITER Organization metrology team maintains a large selection of metrology instruments which are used by its framework contractors and loaned to assembly contractors when loan agreements are in place. This arrangement makes it easier to coordinate the annual calibration required for each piece of measuring and testing equipment to ensure it remains accurate as it undergoes shock, both small and large, or simply drifts over time. “When we purchase an instrument, the manufacturer supplies a calibration certificate indicating conformance to specification and the date the calibration was performed,” says Kwangju Mun, metrology survey technician. “We schedule the next calibration one year after that date.”The team uses a platform from a company called Ape Software, which has become something of a standard for use in large projects that need to show regulatory compliance. During the equipment registration process, technicians enter information such as the calibration interval, who performs the calibration, certificate references, the serial number, maintenance contract details, and pictures. The Ape platform uses a database to track the registered instruments and produces reports in a spreadsheet format, with color-coded messages to indicate when calibration is needed. Specialized reports can be generated to demonstrate regulatory compliance. The software also helps manage the status of each piece of equipment—including who is using it and where it is located. Preparing laser trackers for a field survey. Records are kept of calibration so that each instrument is maintained at optimal performance. During laser tracker annual calibration by the supplier, components are tested and adjustments made if necessary. The supplier also makes sure the absolute-distance meter scale, which is how accurately an instrument calculates distance, remains within the maximum permissible error for the type of device—a value specified by the manufacturer.One component that is calibrated is called the absolute distance meter, which the absolute interferometer (AIFM) uses to provide stable, high-speed absolute distance measurements of moving objects. The absolute distance meter uses the information from the interferometer to compensate for the wobbly wave form when the target is moving, and as soon as the average minimum point on the wave is calculated, the absolute distance meter feeds absolute distance measurements to the interferometer, changing it from a relative interferometer to an absolute interferometer.Other examples of components that need calibration are the embedded meteorology station, which serves as a reference for temperature, pressure, and relative humidity, and the scale bar. "The scale bar is made of invar and it is not very affected by temperature differences, so once it’s calibrated we can use it as a reference during measurements," says Mun.The metrology team calibrates tools more often than annually. “Our instruments are very sensitive and can be affected by shocks—even small ones,” says Mun. “If we know a piece of equipment has undergone shock, we do additional, unscheduled calibration.”The team also does field verification checks before and after each series of measurements. "If the errors observed exceed the permissible maximum error of the equipment under the given conditions—such as distance and temperature—it indicates that the equipment needs to undergo a new compensation process,” says Mun.

The 14th ITER International School (IIS) will be held from 30 June to 4 July in Aix-en-Provence, France, hosted by Aix-Marseille University. The ITER International School aims to prepare young scientists and engineers for working in the field of nuclear fusion and in research applications associated with the ITER project. The school format reflects the necessity of training future professionals on a wide range of interdisciplinary subjects, equipping them with a broad understanding of the skills required to contribute effectively to ITER’s success.The subject of the 2025 school is "Integrated modelling of magnetic fusion plasmas," with a scientific program coordinated by Xavier Litaudon (CEA) and Alberto Loarte (ITER Organization). Reliable predictions of ITER plasmas, spanning the entire cross-section from the plasma core, scrape off layer up to the material surface, are key to the achievement of ITER’s fusion power demonstration goals. These predictions are essential for defining and preparing plasma operational scenarios and analyzing plasma pulses that will be executed in ITER, as well as for evaluating the required control schemes through the simulations of measurements, actuators, and the associated plasma responses. Given the strong non-linear coupling of processes governing burning plasma behaviour, separate modelling of individual processes and/or plasma regions is not sufficient. A holistic, integrated approach is therefore mandatory. The 2025 school will address the current needs and explore the integrated modelling capabilities and validation aspects on existing facilities necessary to prepare ITER operation and support ITER’s scientific exploitation.The first ITER School was organized in Aix-en-Provence, France, in 2007 and focused on turbulent transport in fusion plasmas. Twelve successive schools have followed on a variety of subjects: magnetic confinement (Fukuoka, Japan, 2008); plasma-surface interactions (Aix-en-Provence, 2009); magneto-hydro-dynamics and plasma control (Austin, Texas, USA, 2010); energetic particles (Aix-en-Provence, 2011); radio-frequency heating (Ahmedabad, India, 2012); high-performance computing in fusion science (Aix-en-Provence, 2014); transport and pedestal physics in tokamaks (Hefei, China, 2016); physics of disruptions and control (Aix-en-Provence, 2017); the physics and technology of power flux handling (Daejeon, Korea, 2019); ITER plasma scenarios and control (San Diego, USA, 2022), the impact and consequences of energetic particles on fusion plasmas (Aix-en-Provence, 2023) and magnetic fusion diagnostics and data science (Nagoya, Japan, 2024).Further information on the 2025 school will shortly be available at this address. Find out more about past schools here.

The 2025 Symposium on Fusion Engineering (SOFE 2025) is planned from 23 to 26 June 2025 in Boston, Massachusetts, hosted by the MIT Plasma Science & Fusion Center. Abstract submission has been extended through 24 January 2025.  Early bird conference registration will open on 5 March, the same day abstract acceptance decisions are sent out.Held biennially since 1965, SOFE is coordinated by the Fusion Technology Committee of the IEEE/NPSS (Institute of Electrical and Electronics Engineers/Nuclear & Plasma Sciences Society). It is an international conference open to all engineering, physics and material science disciplines involved in the pursuit of producing the components and systems needed to advance fusion physics and technology. Submit your abstract here.