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ITER NEWSLINE 189
In June this year Steven Cowley, the CEO of the United Kingdom Atomic Energy Authority and head of the Culham Centre for Fusion Energy (CCFE), was appointed by Prime Minister David Cameron as a member of the Council for Science and Technology (see Newsline issue 183). In today's interview with the ITER Newsline, he talks about his new role and the importance of making fusion commercially viable.
Newsline: Steven, can you describe your role as a member of the Council for Science and Technology?
Cowley: The Council for Science and Technology advises the government on strategic issues and how the United Kingdom should position itself. It is made up largely of scientists and engineers, technologists from industry and academia in the UK. What is of great concern in the UK government currently is how to stimulate innovation. How do we produce the next generation of companies that will produce the innovations in our economy? How do we shape the future prosperity of the UK? My other role in life—running fusion in the UK—is very closely related to these two questions. Fusion is not about pure science ... it is about producing an energy source for the future, an energy source that will bring prosperity with it.
Do you think you were appointed because of your leading role in the national fusion program?
It's difficult to speculate why they asked me. I think the UK government realizes that fusion is now a very important part of the research portfolio. Fusion fits right into its vision that the future has to be supported by high technology, and that the ultimate high technology is energy. I think that I am in this role because the government wants sound advice on fusion, on nuclear, on energy...and I have expertise in these areas.
Currently, there are many activities going on worldwide to address the question of how to accelerate fusion research. Is this a question that is being discussed in the UK as well?
I am actually about to head out to Princeton (US) where there is currently an international fusion road-mapping workshop going on ... and, yes, this issue is being discussed at government level here in the UK as well. I think everybody realizes that it would be desirable to have fusion as fast as possible. However, as we are proceeding forward towards fusion, we want to make sure that we don't go down any blind alleys. We want to go as fast as possible, but without stumbling. It would be a shame if fusion stumbled on the way rather than going straight for the goal. That is why ITER is so important.
I think once the burning shots on ITER have been accomplished ... once ITER produces a gain of ten and a stable long-pulse shot ... we will know that fusion is absolutely possible. We will have done it. But what we don't know is how long it will take us to make fusion viable commercially. One of the questions everybody is asking right now is to how to shorten the time after ITER to a demonstration reactor (DEMO). How quickly, after ITER is successful, can we push forward to an actual electricity-producing fusion power plant?
The discussions at Princeton are part of a wider discussion on how fast the fusion community can do that. I think that the more desperate people get for energy, the more pressure we will receive. The UK is very committed to have fusion as part of the energy portfolio in the second half of this century. For that, DEMO has to be operational in the 2040s. People think this is a long time, but it is not such a long time for development, as fusion is such a sophisticated technology. The UK believes that part of the future UK generating base will be fusion, and that this proportion will increase. By 2100, we are perhaps talking about a substantial portion of the electricity generating base in the UK ... and, I am sure, throughout Europe.
The Chinese government is dedicated to building a DEMO reactor and is now investing into the education and training of 2,000 fusion scientists and engineers. Does such news influence the debate in the UK?
I think that news like that does indeed influence the debate. On the other hand, 2011 is an exceptional year with the world's major economies up against the wall. In many respects, looking over at China is less on the mind of politicians than the dangers of cutting research budgets in the UK. The government has maintained strong support for ITER; while many projects have had their budgets reduced, the fusion research budget was maintained. There is some research that is beautiful, that is lovely, it tells us beautiful things about the world. But it doesn't matter very much whether we know it now or in 20 years from now. It is not vital to our future economy and our future survival. That is not true about fusion, it is vital.
This week, on Tuesday, 6 September, the Indian Domestic Agency ITER India signed the Procurement Arrangement for the ITER cryostat, which will be the world's largest high-vacuum chamber, worth approximately EUR 100 million. It is one of the project's largest procurements and thus represents a significant step towards the construction of ITER.
Welded together from thick stainless steel plates measuring between 40 and 180 millimetres, the cryostat forms the vacuum-tight container surrounding the ITER vacuum vessel and superconducting magnets. The massive structure will have to withstand a vacuum pressure of 1 x 10 -4 Pa; the pump volume is designed for 8,500 m³; and it will have a weight of 3,400 tonnes. It will have an outer diameter of 28.54 metres and be almost 30 metres tall.
The steel cylinder will have 23 penetrations allowing access inside of the cryostat for maintenance, as well as over 200 penetrations—some as large as four metres in size—providing access to the vacuum vessel for cooling systems, magnet feeders, auxiliary heating, diagnostics, and the removal of blanket and divertor parts. Large bellows are used between the cryostat and the vacuum vessel to allow for thermal contraction and expansion in the structures.
Due to size and weight limitations, the cryostat will be manufactured in segments in India and a sub-assembly of four sections will be prepared at ITER's site workshop. Finally, the four sections will be assembled into the Tokamak Pit.
The Cryostat Procurement Arrangement was number 59 on ITER's list, bringing to 71 percent the amount of in-kind procurements signed to date for the ITER Project.
Last Wednesday, Tore Supra shipped a large parcel to China. The four-metre-long box, weighing 2.3 tonnes, was addressed to EAST, the superconducting tokamak that the Chinese Academy of Sciences Institute of Plasma Physics (ASIPP) operates in Hefei.
The box contained an "ITER-like" ion cyclotron resonance heating (ICRH) prototype antenna that Tore Supra, the tokamak that CEA-Euratom operates in Cadarache, had tested during a six-month campaign in 2007-2008 in collaboration with Oak Ridge National Laboratory (ORNL) in the US.
The collaboration was recently extended to China; now the joint experimental program to prepare for ITER operations will continue on EAST as soon as the antenna is fitted to the machine.
"This antenna is what we call 'load resilient'," explains Gilles Lombard, a Tore Supra engineer specialized in high frequency heating. "This means that it can withstand strong charge variations like the ones that edge localized modes (ELMs) generate on the edges of the plasma."
As a circular tokamak with no divertor, Tore Supra does not access the "H Mode" that generates ELMs. "However, the charge variations can be mimicked by injecting gas into the plasma at supersonic speed," explains Xavier Litaudon, Head of Plasma Heating and Confinement at CEA-IRFM, the Research Institute on Magnetic Fusion that operates Tore Supra.
Tore Supra used this technique to establish the "proof of principle" of the ITER-like antenna and to validate the codes for electromagnetic calculations that are used to design the actual ITER antenna.
The antenna—which had been in storage for three years—needed a bit of dusting. With some maintenance and adaptation, it will fit perfectly into EAST, a machine about the same size as Tore Supra ... but "H mode" capable.
The parcel should arrive in Shanghai by mid-October and be delivered to Hefei in the subsequent weeks.
The accomplishment of the first welding joint was an important milestone and a demonstration of the acceleration of toroidal field conductor construction in China. Following the successful completion of SULTAN test and clearance of quality control Authorization to Proceed Points (ATPP) in August, ITER China and ASIPP are now preparing for the assembly of the formal toroidal field dummy conductor.
According to the Procurement Arrangement signed between CN-DA and the ITER Organization, China will undertake 7.51 percent of toroidal field conductor fabrication for ITER. During Phase II, a 760-metre dummy copper conductor is required for process qualification.
In 2009, ITER China awarded the first contract for toroidal field qualification conductor fabrication to ASIPP. In parallel to the construction of new fabrication facilities, extensive R&D work and the trial fabrication for the ITER conductor were carried out at Hefei, which is now doted with a 4,000 square-metre workshop and nearly 1,000—metre assembly line.
"The most important thing is to carry out the task strictly in accordance with the contract ... on time and with guaranteed quality and quantity," proclaimed ITER China Head Luo Delong at the ceremony.
A specific subset of neutron diagnostic systems in ITER will measure the emission of neutrons during the fusion reaction and provide real-time information about the level of fusion power. As one neutron is produced by every fusion reaction, measuring neutron output during experimental plasmas can convey important information on the amount and location of fusion reactions.
This month, the Procurement Arrangement for a neutron flux monitor planned for equatorial port 07 was finalized after signature by ITER Director-General Osamu Motojima (5 August) and Head of the Chinese Domestic Agency Luo Delong (2 September). This is the second completed Procurement Arrangement for the ITER Diagnostic Division ... and also the second neutron diagnostic signed (see report on the neutron activation system in Newsline 182). "This milestone is the result of a lot of hard work by both sides and an important step in realizing our joint responsibility in providing the key measurement systems in ITER," commented Diagnostic Division Head Michael Walsh, on the occasion of the signature.
The neutron flux monitor (NFM) is composed of three cylindrical fission chambers containing argon gas and a tiny amount of uranium (235U). Each neutron arriving from the fusion reaction induces a fission event in the uranium layer of the chamber, triggering a pulsed signal that is transmitted to an electronic acquisition system. The pulses induced by individual neutrons can be calibrated and related to the total neutron yield rate in real time, and to total fusion power in megawatts (MW). Each fission chamber contains a different amount of fissionable material and therefore varies in sensitivity, which permits the measurement of a range of neutron yield, from low to high.
In order to increase the probability of fission events, each fission chamber is inserted into a moderator. As the neutrons pass through the moderator, they lose part of their energy and induce a fission event more easily (the lower the energy of the neutron, the higher the probability of a fission event).
The neutron flux monitor for equatorial port 07 is the first of four NFMs planned for the ITER machine. Highly sensitive, it will be used during the early deuterium phase of operation and for initial tritium operation to measure low/medium fusion power levels. Three similar systems are planned at equatorial port 01 for low fusion power measure during the deuterium phase and equatorial ports 08 and 17 for high-power measurement during full tritium operation.
"This diagnostic, which will be located in the cryostat region of the Tokamak between the vacuum vessel and the bioshield, has been a challenge to integrate into the machine," explains Luciano Bertalot, Technical Responsible Officer for this Procurement Arrangement. "This month's signature is the outcome of very efficient collaboration between the diagnostic teams at the ITER Organization and the Chinese Domestic Agency."
Dr. Fang, Diagnostic Division Head for ITER CHINA, added: "China has accumulated experience with diagnostics in related fields and has made specific R&D work related to ITER requirements. It has been a pleasurable collaboration between ITER China and the diagnostics team at ITER. ITER China will soon begin the procurement description preparation and the tendering process for this diagnostic as scheduled."
Without CODAC, the ITER machine would be like a Tower of Babel: systems and components would each speak their own language and total confusion would result.
CODAC, which stands for Control, Data Access and Communication, is the central control system—the "common language" responsible for operating ITER. Section Leader Anders Wallander defines CODAC as "a system which, from an operational point of view, makes one entity of everything."
Over the course of the years, CODAC standards for ITER were established and a documentation package, called the Plant Control Design Handbook (PCDH), was published to provide guidelines and specifications to the industry for Instrumentation and Control (I&C). A reference to the PCDH is now attached to every Procurement Arrangement signed between the ITER Organization and a Domestic Agency.
The ITER machine and plant systems will not be fully operational before the end of the decade but a light version of CODAC—dubbed "mini CODAC"—is already being implemented on the ITER construction site.
"We needed an illustration of what the CODAC system really is," explains Jean-Yves Journeaux, a member of the CODAC team and the responsible officer for PCDH. "We needed to verify that our solutions were efficient and appropriate, and that our clients endorsed them."
The distribution of electrical power to the ITER worksite provided just the "user case" that the CODAC team needed. Until recently, distributing 15kV electrical power to the construction companies on the site (what Journeaux calls the "clients") relied on a rather primitive system. Meters, for instance, were not centralized and had to be read manually.
"We lacked an efficient control and command system," says Joël Hourtoule, section leader for ITER's steady state electrical network (SSEN). "We realized we could provide the CODAC team with a pertinent user case."
What the CODAC Team has implemented for the electrical distribution, command and control on the ITER worksite "is no laboratory tool," stresses Hourtoule. "It is the first truly operational ITER system."
The system core is hosted in two small concrete buildings located at the back of the current office buildings on the ITER site, labelled Load Centre B91 and B92. The two buildings are like twin control towers, collecting and dispatching electrical power as well as data and providing Hourtoule and the operations team with a real-time picture of what's going on, electrically speaking, on the ITER worksite.
The present electrical consumption on the ITER worksite is equivalent to that of some one hundred households (~ 1MW), and significantly more when the concrete batching plants are operating. Consumption will be multiplied by ten when assembly of the ITER poloidal field coils is underway in the Winding Facility and the cryostat is being assembled.
"We're working with Fusion for Energy to extend the use case to the monitoring of the Poloidal Field Coils Winding Facility," says Journeaux. "It will be the first time we work directly with a Domestic Agency on something tangible. For us at CODAC, the 'hands-on' is about to begin."
Beginning Monday, 12 September 2011, over 900 of the world's foremost experts in all aspects of magnet technology will gather in Marseille, France for the 22nd meeting of the biennial Magnet Technology conference (MT-22). First established in 1965, the MT is the world's largest gathering dedicated specifically to advancing the science and technology of magnet applications—the MRI machines that allow for non-invasive examination of the human body and high-energy particle physics helping to understand the universe and the fundamental constituent of matter... A typical example for fusion technology is the manufacturing of powerful, high-field and high-current superconducting cables that will contain, shape, and drive plasmas in fusion devices such as ITER.
"In the four decades since the MT conference began, we have witnessed enormous gains in both the performance and applications of permanent, resistive, pulsed, hybrid and superconducting magnets," says Conference Chair Neil Mitchell. And it is with great pride that this year, which happens to be the 100th anniversary of the discovery of superconductivity and the 50th anniversary of applied superconductivity (which will be celebrated during the conference), the ITER Organization—as the emblematic project that will be pushing the boundaries of existing magnet technology in a wide variety of areas—together with the French Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA) have decided to host this important event, where the most recent developments in magnet technology are exchanged.
"ITER is now building the largest set of magnets ever seen and therefore the ITER Organization is a fitting host for this conference," says ITER Director-General Osamu Motojima. "In the course of the week you will get opportunities to hear about the status of ITER construction and even see some of the prototype components. I think a conference of this type, based on a generic technology, is an excellent opportunity to see how ITER is benefitting from, and contributing to, developments in associated fields.
The record number of 979 submitted abstracts highlights the interest in the field. "This strong interest shows the vitality of our discipline in all the topics of the conference at the moment we are celebrating the centenary of superconductivity and also fifty years of applied superconductivity, which is the main focus of our conference," Jean-Luc Duchateau, the scientific program chair for MT-22, states.
In parallel to the technical sessions of the conference, ITER and CEA are organizing a scientific and industrial exhibition to be held on site at the conference venue, which will allow scientists and engineers involved in magnet technology research to interact with the companies and organizations that are responsible for building the actual hardware that comprises the world's most sophisticated and advanced magnet systems.
A Press Conference will be held at 11:30 a.m. on Monday, 12 September at the Conference Center, Salle Riou. Speakers will be ITER Director-General Osamu Motojima, Maurice Mazière, Director of CEA Cadarache and MT-22 Conference Chairman Neil Mitchell.
More information on all aspects of the conference taking place at the Parc Chanot may be found on the MT-22 web site at www.mt22.org.