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The European Domestic Agency has announced the realization of an important procurement milestone for °ÄÃÅÁùºÏ²Ê¸ßÊÖ: the completion of Europe's share of the niobium-tin (Nb3Sn) superconducting strand required for the fabrication of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's powerful toroidal field coils.   Approximately 380 tonnes of Nb3Sn superconducting strand, or "wire," is required for °ÄÃÅÁùºÏ²Ê¸ßÊÖ's toroidal field magnets. The wire is the key component that will allow the toroidal field magnets to reach 12 T and contribute to the confinement of the plasma. Each strand is less than 1 mm in diameter, and yet can sustain very high current when cooled down to "superconducting" temperatures (-269 degrees Celsius).   The European share of toroidal field strand procurement amounts to 97 tonnes (20.2 percent of toroidal field strands). Two suppliers—Bruker European Advanced Superconductors and Oxford Superconducting Technology—carried out the fabrication. The superconducting wire was produced, tested, approved by the European Domestic Agency, Fusion for Energy, and finally cleared by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization.   Europe is the third °ÄÃÅÁùºÏ²Ê¸ßÊÖ Domestic Agency, after Korea and Japan, to complete toroidal field strand production and all related °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization control points.   The more than 1,500 production units produced by the two manufacturers will be used to fabricate the cables for the European toroidal field coil cable-in-conduit conductor (CICC) lengths.   Fifty percent of conductor unit lengths have already been produced and delivered to ASG Superconductors SpA, the Italian facility in charge of manufacturing the toroidal field coil winding packs. The remaining conductor lengths will be finalized in 2015.

It was in 1968 in Novosibirsk, at the third Fusion Energy Conference hosted by the International Atomic Energy Agency (IAEA), that Russian Academician Lev Artsimovich from the Kurchatov Institute presented some amazing results from the T3 Tokamak: a confined plasma with electron energies up to 1 keV had been achieved, corresponding to temperatures of more than ten million degrees. The news was received at first with considerable skepticism, the fusion physicists who were present remember. But the breaking news proved to be correct and led to a global shift in nuclear fusion research.   Last week, 46 years after that historic Novosibirsk meeting, the Fusion Energy Conference returned again to Russia, this time to St. Petersburg, to take stock of the development prospects for fusion power. Approximately 1,000 people attended the conference, representing 39 Member States and 4 international organizations.   Participants had the chance to tour the exhibition and attend the many presentations and posters on scientific and technological developments in fusion. "Saturated Low-n Kink peeling Mode" or "Electron Bernstein Wave Heating" anyone? "The world has moved on and so has the development of fusion energy," said Alexander Bychkov, the IAEA Deputy Director-General, in his opening speech. "With °ÄÃÅÁùºÏ²Ê¸ßÊÖ under construction in the south of France and plans for DEMO reactors being developed around the world, the focus of nuclear fusion research is slowly shifting from pure research to technology, material science and engineering. This does not mean that pure research is becoming less important, but that other aspects increasingly have to be taken into account as well. In the future, when °ÄÃÅÁùºÏ²Ê¸ßÊÖ will start operation and when DEMO reactors are being designed, the questions of safety, security and even safeguards will grow in importance."   Qualifying °ÄÃÅÁùºÏ²Ê¸ßÊÖ as "one of the most promising projects of our time," the Deputy Director General of Rosatom, Vyacheslav Pershukov, introduced °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Osamu Motojima, who reported the latest project achievements including the completion of the lower basemat of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak Complex and the arrival of the first machine components on site. "Ninety percent of the project's in-kind procurement value is now under contract," the Director-General stressed.   A press conference was held for more than 50 Russian and international journalists at the Efremov Institute, staged right up aginst huge mockups of busbars, fast discharge and switching units. Left to right, presenting: IAEA Deputy Director-General Alexander Bychkov; °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Motojima; Oleg Filatov, director of the Efremov Institute; and Vladimir Vlasenkov, deputy director of °ÄÃÅÁùºÏ²Ê¸ßÊÖ Russia. The head of the Russian Domestic Agency for °ÄÃÅÁùºÏ²Ê¸ßÊÖ, Anatoli Krasilnikov, described the broad scope of Russian contributions to °ÄÃÅÁùºÏ²Ê¸ßÊÖ and the good progress achieved to date, and invited participants to take a technical tour of the Efremov Institute situated on the outskirts of St. Petersburg. It is here where Russian superconductors for °ÄÃÅÁùºÏ²Ê¸ßÊÖ take shape and plasma-facing components are designed, manufactured and tested for their heat resistivity. A press conference was held for more than 50 Russian and international journalists, staged right up against huge mockups of busbars, fast discharge and switching units to help bring home the impressive dimensions of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ plant. When asked for some good arguments against those who question the pace of construction, Oleg Filatov, director of the Efremov Institute, had one short answer: "Look around," he said. "Welcome to the argument factory!"   Although there were no game-changing results reported at the 25th Fusion Energy Conference, there was plenty of news that "expands the frontier of fusion," according to Richard Buttery, Director of the DIII-D Experimental Science Division (US). The number of presentations and posters covering progress in fusion materials such as tungsten reflected the importance of this field of research. Assessments of technological developments in fusion and studies of plasma behavior under extreme conditions were also well represented. The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, with 7 oral presentations, 24 posters and 54 papers, did its part to contribute to the expansion of the fusion frontier.

On 6-7 October, the committee charged with the governance of the Test Blanket Module (TBM) program convened at °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters for its 12th meeting. The TBM Program Committee meets twice a year to manage the various aspects of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ TBM program and to review the implementation of tritium breeding modules, which must be tested in °ÄÃÅÁùºÏ²Ê¸ßÊÖ to demonstrate the capability of achieving tritium breeding self-sufficiency in a future fusion DEMO plant. The committee's findings are reported each time to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council. Significant progress was reported at the 12th meeting. In line with the TBM program schedule, four TBM Arrangements (TBMAs) have already been signed this year (with China in February, Korea in May, and two with Europe in September); the remaining two are planned for signature in the next few months. TBMAs are the documents that govern the activities related to construction, delivery and acceptance testing of the Test Blanket Systems. The successful signatures now open the way to the next phase of the TBM program: conceptual design reviews for the six Test Blanket Systems and the associated °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization activities on integration and maintenance. The outcomes of conceptual design reviews performed in July (for China's Helium-Cooled Ceramic Breeder Test Blanket System and associated °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization activities) and in September (for the Test Blanket System connection pipes) were reported and the Committee noted that the corresponding conceptual design approval is expected before the end of the year. A presentation and assessment of the main outcomes of all conceptual design reviews is planned for the spring meeting of the TBM Program Committee. Good progress was also noted in the R&D activities carried out by all the seven °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members, as the Committee verified and confirmed the main activity milestones planned for 2014 and 2015. Progress was also reported on the activities required for the preparation of Radwaste Management Agreements, which will define how the radwaste related to the Test Blanket Systems will be dealt with during °ÄÃÅÁùºÏ²Ê¸ßÊÖ operation and decommissioning. The Test Blanket Program Working Group on Radwaste Management* reported on the technical work accomplished for the preparation of harmonized data and, in particular, convergence on a common approach for tritium inventory estimates was noted. Agence Iter France detailed the progress made in the assessment of data received from the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members and on the related interaction with ANDRA (Agence nationale pour la gestion des déchets radioactifs), the French agency for radioactive waste management. Agence Iter France also proposed a draft roadmap towards the establishment of the tripartite agreements involving the Host State, °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members and the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, which will establish an agreed framework for the management of the radwaste associated with each Test Blanket System. The proposal was noted by the 12th Test Blanket Module Program Committee and will be further discussed at the next meeting. *The Test Blanket Program Working Group on Radwaste Management comprises °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members' Test Blanket Module representatives; °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization representatives for the TBM Program, radwaste management and safety; legal experts from all the contributing Members; and representatives from Agence Iter France (as the interface between °ÄÃÅÁùºÏ²Ê¸ßÊÖ and the Host country, France).

The Final Design Review for the poloidal field AC/DC converter was successfully held in Beijing, China on 23-25 September. In advance of the meeting—in addition to the routine duties of reviewing design documentation submitted by the Chinese Domestic Agency and its suppliers—the review panel headed by chair Ivone Benfatto of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Electrical Engineering Division faced the difficult challenge of finding flights to China in the context of a major Air France strike. Fortunately, all participants were able to arrive on time and the meeting was completed according to schedule.   According to a Procurement Arrangement signed with the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization in 2011, the Chinese Domestic Agency is responsible for the procurement of the 14 poloidal field AC/DC converter units that will provide reliable, controlled DC power to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ poloidal field magnetic coils and dummy load for site testing.   During the meeting, the Chinese Domestic Agency and its suppliers presented their work on the final design and testing of the poloidal field AC/DC converter system and its main components such as converter transformer and converter modules. Interface requirements, key electrical and mechanical design, and Factory Acceptance Test (FAT) and Site Acceptance Test (SAT) procedures were carefully examined by the review panel members and experts.   The main supplier ASIPP (the Institute of Plasma Physics, Chinese Academy of Sciences) showcased their one-of-a-kind test platform which was designed and constructed to test the °ÄÃÅÁùºÏ²Ê¸ßÊÖ poloidal field converter system at various rated operation and fault conditions to verify their design. Test results of the full-scale prototype using the test platform were essential in the validation of the ASIPP final design.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and Chinese Domestic Agency participants concluded the Final Design Review with a debriefing session to discuss the results of chit categorization and future actions. There were no critical chits and the review panel was confident that procurement can now advance to the next manufacturing review stage on schedule.   The meeting ended in a cooperative spirit with a remark by Peng Fu, chief engineer and °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project manager at ASIPP, who said, "For us chits are not just issues to be resolved, they are good proposals to improve the product and prototype design."

If one excludes such monsters as the Taisun crane at the Yantai Raffles Shipyard, in Yantai China, capable of lifting 20,000 tonnes, the °ÄÃÅÁùºÏ²Ê¸ßÊÖ assembly crane, with a lifting capacity of 1,500 tonnes, can be counted among the strongest in the world.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ assembly crane—actually two 750-tonne cranes working in tandem—will provide synchronized lift and millimetre-scale positioning for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak components. The system will be complemented by two smaller 50-tonne auxiliary cranes.   In July, the European Domestic Agency Fusion for Energy awarded the contract for the design, certification, manufacturing, testing, installation and commissioning of the four cranes to a German-French consortium, NKMNOELL-REEL, formed by NKMNoell Special Cranes GmbH, Germany and REEL S.A.S., France. The contract, worth approximately EUR 31 million, also includes the 120-tonne capacity Tokamak cargo lift that will move activated components from the Tokamak to the Hot Cell facility during the Operation Phase.   The Final Design Review for the assembly cranes, which started off at °ÄÃÅÁùºÏ²Ê¸ßÊÖ on Monday 30 September with the presentation of the design, generated only minor comments.   The design of the cranes must integrate the wider context, taking decommissioning requirements into consideration and also integrating the crane system into the structures of both the Assembly Building and the Tokamak Complex. However the review, chaired by °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Central Engineering and Plant Directorate head Sergio Orlandi, strongly stressed the necessity of integrating the cranes in respect to the wider context—a "double" integration taking decommissioning requirements into consideration in the crane system design, and integrating the crane system into the structures of both the Assembly Building and the Tokamak Complex Building (two constructions that differ in almost all aspects).   "Decommissioning the installation once the °ÄÃÅÁùºÏ²Ê¸ßÊÖ scientific program is completed some thirty years from now is the responsibility of France," explains Sergio. "However, it is rational for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization to design a system that will be used for both the assembling of the machine and for its dismantling. To me, integration for both phases is the key point. And this, as the design review pointed out, can be done with later minor refurbishing"   The assembly cranes will move along rails from the Assembly Building to the Tokamak Complex and back to position the components: the design review stressed the "critical point" of connexion between the two structures that must be addressed. The design review also addressed what Sergio calls "a critical point": the connexion between the Assembly Building and the Tokamak Complex whose combined length will be travelled by the cranes as they move from one building to the other to position the pre-assembled components of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Tokamak.   Central to the connexion challenge are the seismic joints that must allow for the progressive settlement of the 360,000-tonne Tokamak Complex. "After five or six years," explains Orlandi, "the building will have 'sunk' some 7 to 10 millimetres relatively to the Assembly Building which is much lighter. This is normal but it is something we have to take into consideration."   We are still two years away from the beginning of assembly operations. "The crane is a very good crane. We have absolutely no worry about it. But integration has to get deep into our culture. Integration will insure that we have a safe and functional behaviour of the whole system in all conditions."

After an intensive effort to improve the capability of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's central solenoid conductor, the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization has concluded that a technically reliable and economically viable solution has been found. This successful result was obtained through a concerted collaborative effort on the part of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, especially with the Domestic Agencies of Japan and the US, and the international superconductivity research community. The key element of the solution was designing the conductor using a "short twist pitch."  The Japanese strands using this technology confirmed the excellent results obtained during a preceding R&D phase and even enabled the qualification of two additional Japanese strand suppliers for the central solenoid conductor production.   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ central solenoid is one of the most challenging superconducting magnets ever designed. It is made up of a stack of six, independently powered coil modules. The coil stack has a total height of 13.5 metres and an outer diameter of 4.1 metres. One particularity of the central solenoid is that it will be used to inductively drive 30,000 plasma pulses of 15 MA with a burn duration of 400 s.   During their life time, the central solenoid coil modules will have to sustain severe and repeated electromagnetic cycles to high current and field conditions. The most solicited modules are the middle modules in the stack, which will experience up to 60,000 cycles to a maximum peak field of 13 T. This is way beyond anything a large superconducting magnet of this kind has ever experienced. Another challenge is that the °ÄÃÅÁùºÏ²Ê¸ßÊÖ central solenoid is a joint in-kind procurement: the US Domestic Agency is responsible for the central solenoid coil stack, while the Japanese Domestic Agency is responsible for the central solenoid conductor.   A cross section of °ÄÃÅÁùºÏ²Ê¸ßÊÖ's solenoid Cable-in-Conduit-Conductor. Copyright: °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization Like all other °ÄÃÅÁùºÏ²Ê¸ßÊÖ magnets, the central solenoid relies on a Cable-in-Conduit Conductor (CICC) made up of a rope-type cable that is inserted into a stainless steel conduit where a forced flow of supercritical helium circulates. For the central solenoid, the cable relies on 576 superconducting strands mixed with 288 pure copper strands and assembled in five stages around a central cooling spiral. The conduit has a circle-in-square shape and relies on a special high manganese austenitic steel with excellent low fatigue crack growth rate properties at cryogenic temperatures. To achieve the required high field, the superconducting strands are made out of a special alloy made of niobium and tin (Nb3Sn), a material with good current transport properties but that, once formed, becomes brittle and strain-sensitive and which must be handled with care.   The first performance qualification samples of °ÄÃÅÁùºÏ²Ê¸ßÊÖ central solenoid conductors that were tested in the SULTAN facility in Villigen, Switzerland, exhibited excessive degradation as a function of electromagnetic and thermal cycling and did not meet the performance criteria under the SULTAN configuration, which is defined for stable operation of the central solenoid during the life cycle of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ machine.    Following these unexpected results, the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization in early 2010 launched a comprehensive R&D program, with the support of the US °ÄÃÅÁùºÏ²Ê¸ßÊÖ Domestic Agency and Oxford Superconducting Technology (US), to investigate alternative conductor configurations that could potentially achieve more stable performances. This EUR 1.1 million program was successfully completed in May 2012 and a clear solution emerged: among the four variants that were tested, the conductor with the so-called "short twist pitch" configuration behaved as required.    In the "short-twist pitch" set-up, the strands are mechanically better supported and have little room for deleterious bending resulting in almost non-existing degradation as a function of electromagnetic and thermal cycling. The test results even show a slight increase in performance, likely due to compressive strain relaxations that may not be representative of in-coil operation.   The results of the R&D demonstrated that cycling degradation was not inherent to Nb3Sn CICCs and that a technical and economically viable solution could be found to this challenging issue. It remained for the Japanese manufacturers to demonstrate that the short twist pitch configuration could result in the same performance on their strands. In order to do so, the Japanese Atomic Energy Agency (JAEA) prepared a number of samples that were meant to match or even surpass the performances of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization samples. The first of these samples (referred to as CSJA3) was tested in November-December 2012. The tests in SULTAN confirmed the excellent results obtained with the short twist pitch sequence, which demonstrated the best performance. It also enabled the qualification of two additional Japanese strand suppliers for central solenoid conductor production.   The story of central solenoid conductor development is a good example of how scientific collaboration across many borders can lead to solutions for even the most extraordinary challenges of building the °ÄÃÅÁùºÏ²Ê¸ßÊÖ machine—a device that pushes most technologies to their limits and calls for innovative solutions.   Special thanks to Arnaud Devred, °ÄÃÅÁùºÏ²Ê¸ßÊÖ Superconductor Section Leader, for his contribution to this article. 

​Princeton Plasma Physics Laboratory is organizing a colloquium on TFTR  record fusion power shot of December 1993. More information here.

​In order to improve project performance and in light of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project's specific managerial and cultural complexities, an External Management Advisory Board (EMAB) was established earlier this year. This week, the members of the EMAB convened for their first meeting at °ÄÃÅÁùºÏ²Ê¸ßÊÖ Headquarters. The objective of the EMAB is to advise the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization's senior managers and the Director-General on enhancing project and safety culture, a challenging activity in the context of a mega international project with seven Members. Also, the Board is charged with assessing the practical implementation of the set of actions that was decided in response to the Management Assessment carried out in 2013. The Chair of this new entity is Jean Jacquinot, who also serves as scientific advisor to the Chairman of the French Alternative Energies and Atomic Energy Commission (CEA), Bernard Bigot. Other Board members are Michael Tendler, professor at Sweden's Alfvén Laboratory (Royal Institute of Technology); Richard Hawryluk, head of the department of °ÄÃÅÁùºÏ²Ê¸ßÊÖ and Tokamaks at the Princeton Plasma Physics Laboratory (US); Dhiraj Bora, director of the Institute for Plasma Research, IPR (India); and Yuanxi Wan, Academician of the Chinese Academy of Sciences and former Chairman of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Science and Technology Advisory Committee (STAC). °ÄÃÅÁùºÏ²Ê¸ßÊÖ's Colette Ricketts, of the System Management Section, is in charge of the secretariat. "During our first meeting held on 20-21 October, we had a very fruitful discussion," the Board members reported after the first meeting. "We openly addressed issues such as the project's nuclear and safety culture, options for improved alignment between the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and the Domestic Agencies, and last but not least the creation of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Chief Executive Team, (ICET), formed to improve collaboration between all actors of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project." The Board will continue to address key °ÄÃÅÁùºÏ²Ê¸ßÊÖ management issues at its next meeting, scheduled for 11-12 December 2014.

​Research by an international team led by SLAC and Stanford scientists has uncovered a new, unpredicted behavior in a copper oxide material that becomes superconducting — conducting electricity without any loss — at relatively high temperatures. This new phenomenon — an unforeseen collective motion of electric charges coursing through the material — presents a challenge to scientists seeking to understand its origin and connection with high-temperature superconductivity. Their ultimate goal is to design a superconducting material that works at room temperature.   "Making a room-temperature superconductor would save the world enormous amounts of energy," said Thomas Devereaux, leader of the research team and director of the Stanford Institute for Materials and Energy Sciences (SIMES), which is jointly run with SLAC. "But to do that we must understand what's happening inside the materials as they become superconducting. This result adds a new piece to this long-standing puzzle."   The results were published 19 October in Nature Physics.   Read the full article on the SLAC website.

​In the latest newsletter published by Korea's National Fusion Research Institute (NFRI), read how the KSTAR tokamak has topped 10,000 plasma generation experiments since 2009 and how tokamak technologies have found their way into applications in the food and defence industries. The 7th issue of NFRI News is available here.