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ITER NEWSLINE 152
Last week was a tough and meaningful week for us with a series of very intense meetings with the ITER Council's advisory bodies: the Science and Technology Advisory Committee (STAC) and the Management Advisory Committee (MAC). Together, we prepared for the next ITER Council meeting which will take place here in Cadarache on 17-18 November. Before continuing, I would like to express my gratitude to all the people involved in this "tour de force" for their commitment and endurance, whether working for the ITER Organization itself, the Domestic Agencies or as a delegate of a Member. And of course I would also like to thank the Chairman of the STAC, Professor Wan Yuanxi, and the Chairman of the MAC, Professor Gyung-Su Lee, for their much appreciated leadership.
This was a very important week for both the ITER community and for myself, as this was the first time that I had participated in these high-level advisory boards as Director-General of the ITER Organization. I am more than ever conscious of the fact that the stakes are high for the project. While the Council has adopted the Baseline and the good news of the start of construction is spreading, we have been charged by the governing body representing the governments of our Members to bring down the overall cost of the project and to rebuild contingency. At the same time, we have to draw a line and finalize the design.
These are certainly not easy tasks, but we have obliged ourselves to look into every possibility. We are turning over every stone to find viable solutions to reduce the cost of ITER without jeopardizing the scientific goal of this endeavour. As I reported before, over the past months we have put in place several initiatives to identify and pursue ways and methods to contain and reduce the costs of the project. The task force and the dedicated working group have proposed a list of possible means of how to achieve that goal—both in the short- and in the long-term perspectives.
The technical and scientific implications of these possible measures were discussed by the STAC. Among the 22 measures we asked the experts to look into are: a different approach to the cold testing of ITER's magnets; alternative methods for controlling edge localized modes (ELMs); and a new evaluation of the required diagnostics for ITER. All these measures have substantial cost saving potential. As for the ELM coils, we have to be aware that they are not part of the Baseline and only a successful cost containment exercise will make them possible to realize. The centralization of the global cable procurement and CODAC would further decrease the costs, an issue that we will surely investigate. The detailed recommendations given by STAC are now to be approved by the Council, together with the recommendations given by MAC.
The discussion with the MAC, by nature, focused more on the managerial implications that the proposed cost reduction efforts will have on the project. The reorganization of the structure of the ITER Organization will not only reshape its focus, but it will also require some re-planning work to align the new structure with the Baseline.
As requested by the Council, we also presented our proposal for a new staffing policy that aims to find an improved balance between subcontracting and the direct hiring of staff. The international set-up of our project implies a lot of travelling; we aim to reduce the number of missions by increasing the use of visual conference tools. We also propose to implement a tighter control and policy for the use of mobile phones and a revised layout of the office buildings on site that will help us to be more efficient.
The past week with its intense but important discussions showed that we are on the right track. And despite all the unease about the correct path forward we were assured of the continuous support and encouragement from the global fusion community. However, the message we received was clear: we cannot stop here. A lot more work lies ahead if we want to maintain the confidence of the Governments and the people that support us.
Nevertheless, I am confident that together we can make it. ITER must succeed.
Last week, ITER Director-General Osamu Motojima and the Head of the European Domestic Agency "Fusion for Energy," Frank Briscoe, signed the Procurement Arrangement for the European share of the PRIMA neutral beam test facility being built in Padua, Italy. The signature, worth EUR 42 million, symbolizes the launch of another large international enterprise.
Today, neutral beam injectors are used routinely in major fusion devices. The negative ion beams shoot uncharged high-energy particles into the plasma where, by way of collision, they transfer their energy to the plasma particles. But ITER will be larger and more powerful than any existing fusion machine and so will be its heating technology. ITER will be equipped with two neutral beam heating and current drive injectors—each one delivering a deuterium beam of 16.5 MW with particle energies of 1 MeV, and able to operate for long pulses of up to 3,600 seconds. A third neutral beam line will inject a 100 keV/1.5 MW hydrogen beam for diagnostic purposes.
Operating neutral beams safely at such power levels requires some experimental experience. That is why in Padua, home to the Reversed Field Experiment (RFX) Project, the neutral beam test facility is being built.
Europe, India and Japan are the three ITER Members that are contributing to this project which now carries the official name Padua Research on ITER Megavolt Accelerator or PRIMA. PRIMA is made up of two test-stands: SPIDER, the short version for "Source for the Production of Ions of Deuterium Extracted from a Radio Frequency plasma" and MITICA standing for "Megavolt ITER Injector and Concept Advancement" which is the actual prototype of the heating neutral beam operated at 1MV.
India's contribution is to the SPIDER test facility: India will provide the 100 kV acceleration supply and the long-pulse calorimeter for the SPIDER ion source test facility; it may also provide staff for operations and training. Japan's contribution is to the MITICA test facility: Japan will provide the megavolt bushing, the megavolt transmission line and the high voltage part of the megavolt power supply.
The European Domestic Agency is providing all the other components for the two test-beds including the supporting systems, the cooling, the distribution of the insulating gas SF6, the cryosystems, the instrumentation and the control and gas injection systems.
Consorzio RFX and its national organization are providing the facility, including the infrastructure of new buildings covering a surface of two hectares and the adaptation of the existing 400 KV power substation.
Thanks to Deirdre Boilson and Beatrix Schunke, Acting Section Leader and Senior Technical Officer of the Neutral Beam Section, for their contribution to this article.
Copper and carbon are usually not good friends. Copper does not form chemical bonds with carbon and both materials have a large thermal expansion mismatch. Indeed, in many engineering applications, carbon is used as a stop-off to prevent two metals from joining.
However, in the ITER divertor copper and carbon must be intimately connected to ensure the removal of the extremely high heat fluxes which can reach up to 10 MW/m² for up to 3000 cycles and 20 MW/m² for 300 cycles. As a consequence, the development of a suitable high heat flux technology for the divertor has been one of the technically most challenging R&D efforts of the project.
Following the successful qualification phase in 2008, the Japanese Domestic Agency (JA-DA) in June 2009 started the procurement of the outer vertical target, which is subject to the highest heat load among all the in-vessel components. It consists of a lower straight part, faced with carbon armor, an upper curved part with tungsten armor and a steel support structure.
In view of the start of the series production for this component, the JA-DA has completed a study aimed at consolidating the concerned technologies and at improving their reliability. They have recently qualified a new copper interlayer, placed between the carbon plasma-facing material and the copper alloy cooling tube, with an intermediate thermal expansion. As a consequence, they could better bond the two diverse materials and develop a very reliable joint. The occurrence of possible cracks at the joint interface during the cooling phase of the joining process could be suppressed by mitigating the mismatch of the thermal expansion.
Three relevant mockups were manufactured with this optimized interlayer and none of them showed any evidence of defects. Then, they were all subject to high heat flux performance tests at 20 MW/m² for 1000 cycles, which is more than three times higher than required for operations in ITER. The thermal response of all the tested mockups was very stable and no evidence of damage was detected. Takeshi Hirai, the Technical Responsible Officer for the divertor outer target within the ITER Organization, can thus now look toward the future manufacturing activities with even higher confidence.
T-15 produced first plasma in 1988, demonstrated the steady-state regime of its magnetic system operation, carried out about a hundred shots but never operated at full capacity. "We would have needed some $12 million to operate it annually," remember both Englen Azizov, the Director of the Moscow Institute of Tokamak Physics, and Oleg Filatov, the Director of the Efremov Institute in Saint Petersburg. "We never had enough money to start real operations ..." The machine, as a consequence, was shut down in 1995.
Now, fifteen years later, T-15 is back on stage for a spectacular upgrade aiming at ambitious results.
T-15 MD, "MD" for Modified Divertor, will use most of the original T-15's "existing infrastructure." Systems such as power, vacuum, heating and diagnostics, which account for 80 percent of the total cost of a tokamak, will be reused in the new installation.
T-15 MD will eventually trade T-15's original "circular limiter"—like the one in Tore Supra—for a graphite divertor designed to withstand heat loads in the range of 20 MW/m², comparable to that of the ITER environment. Other upgrades include modernization of the heating and current drive systems that will enable a significant increase of heating power (up to 20 MW) and pulse durations of up to 1,000 seconds.
Final design of the new machine should be complete by 2011 and by 2014 T-15 MD should produce first plasma. Experiments in the more "ITER-like" configuration could begin in 2018. The upgraded Russian tokamak will extend the operational domain of "ITER-complementary machines" and contribute to the determination of the optimal parameters required by future reactors.
"We do not want to repeat what has already been done in other machines," explain Azizov and Filatov, "we want to explore."
Hybrid concepts are among the directions T-15 MD could explore. Hybrids proponents claim they have a much better use for the highly energetic fusion neutrons than just having them "heat" the water that circulates inside the first wall's blanket. They want to use their energy to induce fission reactions in a fertile blanket of natural uranium or thorium. This is what both Azizov and Filatov mean when they say: "Fusion can help fission."
In this perspective—which is heresy for many fusion purists—T-15 MD would be a "hydrogen prototype" that would confirm some of the physics needed to launch a "very preliminary" demonstrator for a hybrid reactor. Conceptual design for this project, already named TIN-1, could begin as early as 2011.
"Whatever direction we take," say the two Russian scientists, "we need ITER to succeed." While T-15 MD will have a full-time job in support of ITER, it will also do a little work on the side for the hybrid option being contemplated by some countries.
On 22 September this year, Hiromasa Ninomiya was appointed Head of the ITER Japanese Domestic Agency based in Naka. As Head of the JA-DA, he takes over from Hideyuki Takatsu who has taken on the role of Toshihide Tsunematsu who passed away this summer.
Hiromasa Ninomiya is a fusion thoroughbred. After he graduated with a Master's in Nuclear Engineering from Hokkaido University, he entered JAERI in 1974 and joined the JT-60 project (then in its design phase) to lead the construction of the plasma control system and the MHD analysis and operation scenario systems. From 1985 on, he participated in the first experiments of JT-60, and in 1988 he took part in modifying and updating the machine leading to its new title JT-60 Upgrade.
From 1994 on, Hiromasa Ninomiya supervised the experiments performed on JT-60 Upgrade and he conducted the plasma physics activities as Head of the Experimental Laboratory, Deputy Director and Director of Experimental Department. He further contributed to the ITER Physics Activity and the International Tokamak Physics Activity.
In 2007 Ninomiya assumed the role of Deputy Director-General, Fusion Research and Development Directorate of JAEA and in 2009 he became Director-General of the Fusion Research and Development Directorate and Director-General of the Naka Fusion Institute.
Having spent a lifetime developing and building fusion machines, Hiromasa Ninomiya is now eager to see fusion adding to the energy grid.
The ITER Council Test Blanket Modules (TBM) Program Committee came together in Cadarache on 22 and 23 October. The Committee is charged with the governance of the TBM Program and it serves as an advisory committee for the ITER Council on this matter. It is formed by one governmental representative from each ITER Member and up to three experts per ITER Member from the various national laboratories and universities involved in breeding blanket R&D and in the TBM Program.
In its fourth meeting since its implementation in March 2009, the TBM Program Committee addressed the ITER Organization's estimates on the required staff and hardware cost related to the TBM Program. The technical discussions addressed the progress made by each of the seven TBM teams on various R&D activities, the ITER strategy on RAMI and the estimations of the expected head loads on the TBM's first wall during the various ITER operation phases.
A very important issue for the TBM Program will be the signature of a TBM Arrangement (TBMA) to be done for each test blanket system between the ITER Organization and each ITER Member acting as TBM Leader. The ITER Organization thus presented the procedure in order to achieve the signatures and a proposal for a Generic TBMA to be used as template for each of the six specific TBMA. The Program Committee now has time until the end of the year to make its comments. The objective is to have the final version of the generic TBMA by February 2011 enabling the parties to sign most of the TBMAs in 2012.
The TBM Program Committee further recognized the importance of the standardization of the maintenance scheme for the Test Blanket Modules including remote handling procedures and encouraged the ITER Organization to develop the necessary mechanisms in collaboration with TBM teams.