For eight years, between 2012 and 2020, a large concrete batching plant operated on the ITER platform. Mixing gravel and sand, cement, water and additives, it produced a wide range of concrete formulas, each adapted to the specific requirements of the ITER buildings and structures. Delivered directly to the necessary areas by way of powerful pumps and extended booms, or snaking its way through piping laid inside the buildings, approximately 120,000 cubic metres of concrete were used during the civil works phase of Tokamak Complex construction.  The age of concrete has waned on site and for the relatively small quantities still needed, ITER now depends on a batching plant located six kilometres away in the village of Vinon-sur-Verdon. Distance and delivery time are not an issue, provided concrete is transported in a mixer truck directly from the plant to the pouring site. In some instances, however, no truck, pump or piping can access the pour location and a quick solution must be found to deliver the required volumes of concrete where they are needed. Concrete is like cake mix : depending on its formulation and viscosity, it only remains usable for a defined amount of time. “In order to remain within the workability window, certain operations in certain areas of the buildings require considerable organizational and human effort,” says Armand Gjoklaj, a civil nuclear engineer in ITER’s Civil Engineering and Interface Project. Initiated in September, the backfilling of openings created for busbars in the concrete slab between levels 3 and 4 of the Tokamak Building perfectly illustrates the challenges the teams are facing.  The work location in question, on the rim of the tokamak pit, is a closed area that is submitted to strict cleanliness protocols. The blue ovals indicate the approximate position of the busbar openings around the north part of the rim. The openings are located just above the upper pipe chase mezzanine, which accommodates the primary loop of the machine’s cooling water system. The 1.45-metre-thick slab is made of high-density borated concrete and will act as a nuclear shielding and confinement barrier when ITER enters operation.The area, on the rim of the tokamak pit, is restricted and subject to strict cleanliness protocols: workers must wear white lab coats and special shoes, no dust must be generated, not a single drop of concrete must be projected, and the pouring must be done under sealed plastic tents. Concrete pouring in these conditions looks almost like a clean room operation. Although the quantities needed to fill the busbar penetrations are small (one cubic metre per opening on average) the concrete formulation is the “heaviest” of all those implemented in ITER construction. Whereas one cubic metre of standard raw concrete weighs approximately 2.2 tonnes, the formulation implemented here is more than 60 percent heavier (3.6 tonnes).  The skip containing the concrete necessary to fill an opening (one cubic metre on average) is now attached to the overhead crane. Workers are wearing white lab coats and special shoes in observance of the cleanliness protocol that applies to this “closed zone.” The clock starts ticking as soon as the concrete batch has been mixed at the plant. From that moment on the teams have no more than 150 minutes to deliver, via the temporary cargo lift¹, the required volume of concrete to the work area. Two-and-a half hours might seem like a comfortable amount of time, but the sequence of operations and the successive transfers from one container to another makes for a very tight schedule. Two main constraints need to be taken into account. One is the “workability” of the concrete batch (how long it remains usable); the other is the handling capacity of the cargo lift, which is limited to 8 tonnes. The skip is now positioned close to the sealed tent that covers the opening. The skip's chute is guided manually towards the opening and as soon as the valve is opened, concrete starts rushing out. The mixing truck contains two cubic metres of high-density concrete, amounting to approximately to 7.2 tonnes. With the added weight of the skip, the load would exceed the cargo lift capacity. Once the mixing truck has parked at the foot of the Tokamak Building in the excavated zone reserved for the Hot Cell, half of the concrete is emptied into a one-cubic-metre skip. A telescopic crane lifts the skip and empties it into two or three much smaller containers that are swiftly moved by forklift to the cargo lift platform. “By using smaller skips, one of 500 litres and two of 250 litres, we remain within the handling capacity of the forklift and we can spread the load evenly inside the cargo lift,” explains Bruno Pinard-Legry, the site engineer for the contracting companies Nuvia-GTM Sud, both subsidiaries of Vinci Construction.Like an oversize elevator, the cargo lift moves the skips up five levels and delivers them to a waiting forklift at Level 4. The forklift (or a pallet jack for the smaller skips) transports them over a short distance to the work area, where they are emptied into a skip whose capacity matches the quantity of concrete needed to fill a busbar opening—generally in the range of one cubic metre.Attached to the overhead crane, the skip is lifted and positioned above the opening to be filled. The skip's chute is manually guided towards the opening, a valve is opened, and concrete starts rushing out. Eighty-five minutes have elapsed since the mixing truck left the batching plant. The opening is now filled and the high-density concrete is being vibrated so that it settles in a homogeneous manner through the rebar. "Curing” will take one week; full compressive strength will be obtained in 28 days. In the meantime, five levels below, the same sequence of filling, lifting, moving and emptying has started in order to deliver the second half of the mixing truck’s load. “The timing of the two operations is crucial. Within the 150-minute envelope, we allow no more than 15 minutes for contingencies,” says Pinard-Legry. “If we’re late and exceed the workability duration of the concrete, we’ll either have to throw it away if it is still inside the mixing truck, or evacuate it from Level 4, which would be exceedingly complicated…”Lessons learned from previous concrete pouring operations and precise “chrono analysis” of the filling of the first busbar opening in September have resulted in a smooth process that runs like clockwork and reconciles the rough reality of concrete pouring and the demands of a clean room operation. The last of the 15 openings should be filled this week.¹The cargo lift presently in operation is a temporary device that will be replaced with a considerably more powerful system, designed to transport activated components (up to 120 tonnes) from the Tokamak Building to the Hot Cell during ITER operation. 

The 13th ITER International School concluded successfully in Nagoya, Japan, on 13 December after five days of lectures and discussions. Nearly 200 people from 21 countries participated. The 2024 ITER International School on magnetic fusion diagnostics and data science was successfully held from 9 to 13 December. The event gathered 199 participants from 21 different countries, representing a diverse and international community of experts in the field. The lectures were delivered by 19 prominent specialists in diagnostics and data science for magnetic fusion devices.The ITER International School was the 13th in the series, which alternates between sites within the ITER Member countries and Aix-en-Provence, France, close to where ITER is being constructed. This time the school took place in Nagoya, Japan, hosted by the National Institute for Fusion Science (NIFS). The venue was the Nagoya Prime Central Tower, which provided excellent logistical support and facilities and allowed the participants to also enjoy the vibrant atmosphere of Nagoya’s city centre. A notable contribution to the success of the school was made by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), which provided financial support for the school, and NIFS, which played a crucial role in hosting the event.This year’s school focused on magnetic fusion diagnostics and data science. Diagnostics are key to the achievement of ITER fusion power demonstration goals, and they require the application of a wide range of techniques. But diagnostics are not enough to ensure ITER's success; only through the advanced analysis of the data they provide will it be possible to guide the experiments towards their fusion power goals. Lectures spanned a wide range of topics, from focused talks on the design and application of single diagnostic systems to discussions of advanced data-driven and physics-informed machine learning techniques. The emerging symbiotic relationship between fusion diagnostics and data science was a key theme during this year’s school. Exchanges between participants highlighted how the fields of fusion diagnostics and data science are increasingly reliant on one another—with fusion diagnostics providing the essential data to data science models, and data science assisting with diagnostic design, calibration, fusion data and fault detection. A day in the life of—the data science lectures covered a wide range of topics with domain experts presenting talks ranging from machine learning fundamentals to data assimilation and integrated modelling. Approximately 50 diagnostics will be installed on ITER, distributed in ports, on the vacuum vessel surface, and in the divertor. These diagnostics will measure more than 100 parameters necessary for control of the plasma and first wall processes in order to achieve the required goals and to gain the knowledge needed for future reactor designs. The diagnostics on ITER will be subject to new challenges unprecedented in today’s tokamaks. The diagnostics will operate in a nuclear environment, which requires the design to mitigate atomic transmutation, radiation damage, and thermo-electric effects, as well as to cope with nuclear heating. Since ITER is a nuclear facility, the design, manufacture and installation of diagnostic components is subject to safety and quality requirements, in particular for installation on nuclear confinement barriers such as the vacuum vessel, vacuum vessel feedthroughs and windows. The school discussed the key fusion plasma diagnostics and how these will be implemented in ITER as well as in current tokamaks.The application of data science to problems in magnetic fusion shows great promise. This year’s school highlighted the increasingly important role of scientific machine learning within the magnetic fusion field. The data science lectures covered a wide range of topics with domain experts presenting talks ranging from machine learning fundamentals to data assimilation and integrated modelling. Impressing results from the TCV tokamak in Switzerland showed how advanced machine learning models are assisting plasma control systems in disturbance and disruption avoidance.The school invited students to compete in three data science challenges. These challenges were constructed from real tokamak data recorded by the MAST tokamak in the UK and hosted on the Kaggle platform. The fair-mast dataset provided the students with valuable lesson in the value of truly findable, accessible, interoperable, and reusable (FAIR) fusion datasets. Students were invited to train machine learning models to predict plasma current from discrete magnetics data, plasma volume from frames extracted from a visible spectrum camera, and the structure of magnetic field lines from a diverse set of diagnostic data. Competition in all three challenges was intense with competitors frequently switching positions on the public leaderboards during the week as new machine modelling techniques were learned or data insights applied. While the competition stage of the three data science challenges is now closed, these challenges will remain accessible on the Kaggle website if you would like to have a go. We wish you the best of luck if you do! Speaking at the press conference organized by K. Nagaoka, Vice Host Country Chair, were (left to right): S. Benkadda, IIS2024 Director; Y. Kamada, ITER Deputy Director-General; Z. Yoshida, Director General of Japan's National Institute for Fusion Science; D. Baba, Director for Fusion Energy, Ministry of Education, Culture, Sports, Science and Technology and Cabinet Office; and K. Ichiguchi, Host Country Chair. A press conference was also held just before the opening of the school to explain the overall aim and organization of IIS2024 and to answer questions. A domestic television station introduced the ITER International School and ITER in its evening program. Two newspapers ran articles about the school. In addition, a live broadcast for the press conference, opening, and overview talks of ITER and NIFS was distributed on a Japanese video distribution site, attracting over 4,000 viewers. The school was well publicized in Japan; see some sample videos here, here and here.The quality of the work presented during the two poster sessions held at this year’s school was very high. The school participants along with the scientific committee selected the following six participants to award their outstanding research work with the presentation of a large format photo book describing progress on ITER construction from 2013 to 2024:Andrew David Maris, Massachusetts Institute of Technology, USA. “Prediction & real-time control of the density limit via edge collisionality” Tetsuji Kato, The University of Tokyo, Japan. “Energy exchange between electrons and ions in ITG-TEM turbulence”Joseph John Simons, The Graduate University of Advanced Studies, SOKENDAI, Japan, “Simulation of Doppler-free spectra using the Collisional-Radiative model” Geunhyeong Park, University of Science and Technology, KFE, Korea. “Study of Real Time Magnetic Islands Using Thomson Scattering Diagnostics in KSTAR” Arthur Gaetano Mazzeo, North Carolina State University, USA. “Development and Testing of LUPIN: A High-Density RF Ion Source for Enhanced NBI on DIII-D” Miriam La Matina, Università degli Studi di Padova, Centro Richerche Fusione, Italy. “Experimental analysis of ELM precursors with the Thermal Helium Beam diagnostic at TCV” Tour of the Large Helical Device and control room at the National Institute for Fusion Science. The data science challenges closed on the penultimate night before the week ended, allowing the following list of winners for each of the three challenges to be announced at the closing ceremony. The winners were presented with real sections of super-conducting cable used to wind ITER’s toroidal field coils.MAST Plasma Current challenge: Fumiya Adachi, The University of Tokyo, JapanMAST Plasma Volume challenge: Naoya Mamada, The University of Tokyo, JapanMAST Plasma Equilibrium challenge: Yoshihiro Osakabe, Hitachi, Ltd. JapanOne of the highlights of the school was the visit to the National Institute for Fusion Science, allowing school participants to see cutting-edge facilities first-hand. Three tours were provided: one on the Large Helical Device (LHD) and the control room, another on virtual reality and supercomputers, and a third on plasma heating beam development and fusion reactor engineering facilities. LHD, one of the largest fusion devices in operation worldwide, is a superconducting stellarator device characterized by a heliotron magnetic field configuration that was originally developed in Japan.Overall, the 13th ITER International School was a resounding success, bringing together a diverse group of participants from around the world to exchange knowledge, share experiences, and foster collaboration on diagnostics and data science for magnetic fusion devices. The support from Japan’s MEXT, NIFS, the ITER Organization, the US Burning Plasma Organization, the International Atomic Energy Agency, and Aix-Marseille University greatly contributed to the success of this event.The slides of the lectures will be available later this week on this ITER webpage together with the information on past ITER International Schools.*Article authored by IIS2024 scientific program coordinators Masayuki Yokoyama (NIFS), Kenji Tanaka (NIFS), Martin Kocan (ITER) and Simon Mcintosh (ITER); host country committee members Katsuji Ichiguchi (chair, NIFS), Kenichi Nagaoka (vice-chair, NIFS); local organizing committee chair Hiyori Uehara (NIFS); school director Sadruddin Benkadda (Aix-Marseille University/CNRS); and chair of the scientific committee Alberto Loarte (ITER).

Next April, two important fusion events will be sequenced into a single intensive week. The second ITER Private Sector Workshop will be hosted at ITER on 22-23 April, and the ITER Business Forum (IBF/25), a fusion supply chain event hosted by Agence Iter France, will be held for the first time in several years in Marseille, on 24-25 April. Both events will feature ITER worksite tours, technical panels, networking dinners, and opportunities to consult with technical experts; the IBF will also host a fusion technology exhibition and enable one-on-one B2B meetings with supply chain companies. And for the first time, the IBF will welcome fusion start-up initiatives and give attention to the private sector’s supply chain needs.  Historically, Agence Iter France has structured the IBF to highlight upcoming procurement opportunities in the ITER project. This has led, naturally, to heavy representation by companies across the future supply chain. Success stories, the latest in ITER component deliveries, repairs achieved, lessons learned, relevant technological breakthroughs, and the challenges that lie ahead are all part of the program.Recognizing the emergence of private sector supply chain needs, this IBF will open its doors to participants who are designing, constructing and managing fusion projects funded by private sector investments. For supply chain companies, this offers the opportunity to learn about a broader range of procurement needs. For startups, it enables concentrated access to a global set of companies with fusion-specific capabilities. For ITER, it is a natural progression toward sharing with fusion startups not only the knowledge accumulated over decades, but also the expertise and partner relationships that may be suited to new markets.The ITER Private Sector Workshop will also be different in 2025. The May 2024 workshop sought to establish a baseline of knowledge by answering three questions for each initiative: “What is the your current level of achievement?” “What are the remaining challenges to bring your fusion approach to fruition?” and “How can ITER help?” The next workshop will provide updates, but will focus more directly on solutions: who is doing what to address the common remaining challenges?More details to come: stay tuned. 

The physicists and engineers who worked with him, some as early as the late 1960s, gathered at the French Alternative Energies and Atomic Energy Commision’s Cadarache site (CEA-Cadarache) last week to pay a tribute to Robert Aymar (1936-2024), the physicist who pioneered French fusion research and later headed the ITER project for 10 years (1993-2003). Jean Jacquinot, who joined CEA’s embryonic fusion department in 1961 and played a key role in the ITER negotiations four decades later, remembered the “leader” who fought to reorganize French fusion research in the wake of the “May 68” movement, when authorities and the “old world” were challenged throughout Europe. ITER Director-General Pietro Barabaschi, who worked alongside Aymar during the Engineering Design Activities in the following decade praised his “empathy,” “honesty,” and “skill” in managing stakeholders.Jacquinot, Barabaschi and a few others who had worked with Aymar in different circumstances acknowledged him as a mentor and an enduring inspiration.In 1977, Aymar initiated the Tore Supra project at CEA-Cadarache and headed it through construction and early operation (1988). A symbol, under the name WEST, of international fusion cooperation, the device has been equipped with a tungsten divertor and now acts as a major test bed for ITER. The lobby at the entrance of the building that hosts WEST will from now on bear Robert Aymar’s name.

During the fifth annual ITER Awards ceremony in December, prizes went to the teams with a strong track record of delivering in 2024. The ITER "family" gathered on Wednesday 11 December for a festive few hours and looked back on a year defined by challenge and hard work. "In every culture, the end of a year is a time of transition, a change of season and a cause for reflection," said the host for the evening, ITER Director-General Pietro Barabaschi. "Tonight we are celebrating two years of a profound, extended transition."The Director-General took time to extend thanks for the many individual efforts that may go unnoticed, but that have led over time to changes for the better. He also spoke of team efforts that have resulted in a marked change of mood and improved performance overall—noting, in particular, that the execution of the project's commitments budget this year will come in at or around 100% for the first time. He extended special recognition for project contributors responsible for industrial safety, the relationship with the French nuclear regulator, quality, human resources, communication, assembly, and the project's updated 2024 baseline proposal—while adding that not every group could be cited. The evening was also a celebration of Korean culture through traditional dance, a demonstration of K-pop, and Korean food. As every year, the evening was organized around the culture of one of the ITER Members. The evening started with a special guest, Ambassador of the Republic of Korea Seoung-hyun Moon, who invited attendees to enjoy Korea's "most well-known cultural exports—traditional dance, K-pop and Korean food."Then it was time to announce the annual ITER Award winners. For four categories, awards were determined according to a vote by staff; for a fifth, the Director-General makes the annual choice to recognize a fifth team for special recognition.2024 resultsThe Component Delivery Team Award went to the joint team responsible for vacuum vessel and thermal shield delivery and repair (ITER Organization/Fusion for Energy (Europe)/ITER Korea/ITER India) for the recent delivery of the first European sector and the final Korean sector, as well as the to-specification repairs of the ITER vacuum vessel and thermal shield.The Installation/Assembly/Construction Team Award went to the Sector Module Assembly Project/Machine Assembly Program team (ITER Organization staff plus the CNPE Consortium, Construction Management-as-Agent and other contractors) for restarting the assembly process of the ITER vacuum vessel in 2024, beginning with the sub-assembly process on large tools in the ITER Assembly Hall.The Best Support of the ITER Project Award went to the baseline development team for the preparation of the baseline proposal and documentation, the presentation of the proposal to the ITER Council and other governing bodies, and achieving the ITER Council's endorsement of the "overall approach."The Special Contribution Team Award went to all interim staff for "constant and reliable support across all ITER Organization functions."The Director's Choice Award this year went to the ITER procurement team in charge of managing the main construction/assembly contracts.   The ITER community came together for an end-of-year get together and award ceremony on Wednesday 11 December 2024. The ITER Director-General concluded the first half of the evening—before guests were invited for dinner and dancing—with a round of thanks for ITER staff, contractors, ITER Project Associates and interim staff. "I sense a change in mood. Much remains to be done but we have many causes for celebration this evening. Our track record gives us substantial reason for hope and optimism." He also extended his gratitude for the family and friends that support ITER personnel every day. "We could not do this without you!" 

The 360° virtual tour of ITER construction has been updated with drone footage from October 2024. Discover the principal buildings of the ITER worksite, and the equipment inside, by clicking on and rotating the 360° photos.Accessible from the NEWS & MEDIA pages of the ITER website or by clicking on the link below, the 2D tour requires no special equipment to enjoy. If you do have 3D glasses, click on the yellow goggle symbol at the top of any screen.Click here to see the latest 360° ITER virtual tour.