°ÄÃÅÁùºÏ²Ê¸ßÊÖ

There was a time when progress in Tokamak Complex construction was easy to follow. Excavation in 2010; the creation of the ground support structure and seismic foundations from 2010 to 2014; the achievement of the concrete "floor" (the B2 slab) in 2014; and finally the erection of the first levels of the Tritium, Tokamak and Diagnostics buildings—each operation appearing to the non-specialist as having obvious and clearly defined parameters*. Things began to change with the construction of the Tokamak bioshield, the massive circular structure at the centre of the Tokamak Complex. As intricate formwork was installed all around to match the advancing work, what was happening inside the "Pit" became harder and harder to ascertain. Seen from one of the worksite cranes on 9 June, the complexity around the bioshield seems to reach an all-time high: what to make of this giant "wool ball," half concrete and half steel?   Ten days later, with a large part of the formwork and scaffolding removed, the details of the Tokamak bioshield have at last become easier to "see" for the non-specialist. The two above-ground levels are now clearly defined: Level 1 (L1) can be distinguished by the oval openings created for the neutral beam injection system; Level 2 (L2) has regular 4-by-4-metre penetrations that will allow system equipment such as magnet feeders, remote handling, heating and diagnostics to reach the machine.   In some places, steel rebar is already in place for Level 3 (L3), which will rise eight metres above L2. Contrary to L1 and L2 it will be a "blind wall," with no penetrations whatsoever.   Ten days later, with a large part of the formwork and scaffolding removed, the details of the Tokamak bioshield have at last become easier to "see" for the non-specialist. Looking down into the "arena" we can see new steel structures and a small overhanging workshop that are in place for the installation of a temporary cap that will completely remove the basement levels inside the bioshield from our view. Its purpose is to protect workers at the B2 level as they create the reinforced concrete crown that will support the cryostat and—ultimately—the vacuum vessel.   As a result, this photo offers one of the last opportunities to peek into the depths of the "well" that will accommodate the machine.   *Retrace the history of Tokamak Complex construction on the Building °ÄÃÅÁùºÏ²Ê¸ßÊÖ section of our website (Construction Archives).  

Plasma is like a tenuous mist of particles—light atoms that have been dissociated into ions (the atom nucleus) and free-roaming electrons. In order to study plasma physics or to create the conditions that make fusion reactions possible, plasma must be heated to temperatures in the range of 150,000,000 °C—a feat achieved by communicating considerable quantities of energy to the particles. In an actively-cooled antenna, the quality of the welds, joints and surfaces is paramount. "We have to absolutely guarantee 'zero leaks,'" explains Jean-Michel Bernard, the head of the Plasma Heating Group at the French Institute for Magnetic Fusion Research (IRFM). In tokamaks, the technique most generally implemented is based on radio frequency (RF) waves, similar to the "waves" that carry radio programs over long distances.   But whereas the non-stop broadcasting of news or music from one end of a continent to another only requires a few dozen kilowatts of power, heating a plasma just a few centimetres away demands several megawatts.   In both cases, an antenna does the delivering: a thin metallic structure for radio; a massive, more complex antenna for plasma.   A few hundred metres from the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site, in a workshop near the tokamak WEST (the former Tore Supra, now equipped with an °ÄÃÅÁùºÏ²Ê¸ßÊÖ-like divertor) such an antenna is in the last stages of assembly.   The 4.5-metre-long, three-tonne component is one of three identical antennas that will deliver radio waves into the plasma. Together, they form the ion cyclotron resonance heating system (ICRH), which, along with two lower hybrid¹ antennas, will heat WEST plasmas.   "The objective is to heat the plasma in order to deposit an °ÄÃÅÁùºÏ²Ê¸ßÊÖ-relevant heat load of 10 MW per square metre² on WEST's tungsten divertor," explains Jean-Michel Bernard, the head of the Plasma Heating Group at the French Institute for Magnetic Fusion Research (IRFM).   Although the antenna itself is not "°ÄÃÅÁùºÏ²Ê¸ßÊÖ-like," the heat load and the tungsten divertor are—once fully equipped with its heating system WEST will be an important test bench and risk limiter for °ÄÃÅÁùºÏ²Ê¸ßÊÖ.   WEST's ICRH antennas were designed by engineers of the French Alternative Energies and Atomic Energy Commission (CEA) within the framework of a European collaboration with Belgium, Germany and Italy. Most of the antenna elements were produced by the Institute of Plasma Physics (ASIPP) in China as part of a collaboration initiated in 2013.   The antenna design draws a lot (and cannibalizes a few parts) from the "ancestors" that operated for more than 20 years in Tore Supra.   There are however two major differences. The first is related to ELMs—those bursts of energy and particles that are akin to solar eruptions and can represent 5 to 10 percent of the total energy stored in a fusion plasma.   For reasons that have to do with plasma shape and operational regime, ELMs did not occur in Tore Supra. They will, however, occur in WEST, causing sudden heat loads and variations in the density of the plasma—a phenomenon that will reduce the efficiency of the radiofrequency power coupling and can threaten the integrity of the system.   "Variations in the density of the plasma generate variations in the loads that are fed back to the antenna. In order to protect the system's integrity while maintaining an optimal power coupling, we need to have devices—impedance transformers, variable capacitors, etc.—that allow for adaptation and power modulation."   The second major difference lies in the so-called "continuous wave" operation.   In order to create °ÄÃÅÁùºÏ²Ê¸ßÊÖ-relevant conditions and contribute (along with the lower hybrid system) to delivering the required heat load to the divertor, each ICRH antenna in WEST needs to operate at a power level of 3 MW for 30 seconds, or 1 MW for 1,000 seconds.   There is no way to achieve such numbers, ten times higher than in Tore Supra, without actively cooling the antennas.   "In terms of construction and assembly there is a world, a whole ocean, between a partially-cooled 'inertial' antenna like the ones we had in Tore Supra, and an actively-cooled component like those WEST requires," emphasizes Jean-Michel. "We have to absolutely guarantee 'zero leaks,' which is extremely challenging in terms of the mechanics of joints and surfaces."   At every stage of fabrication and assembly the sub-components are leak-tested and, when completed, the whole antenna will go through a battery of helium leak tests under relevant temperature conditions.   In the IRFM workshop, the first ion cyclotron antenna is in the final stages of completion and will be installed on WEST in the coming weeks, in time for the September experimental campaign. The second has just arrived and the third will arrive from China in July.   Standing on its steel frame, looking like an oversized, tormented trumpet, the ELM-resilient, continuous-wave antenna is an impressive piece of work.   It will, however, be dwarfed by its °ÄÃÅÁùºÏ²Ê¸ßÊÖ equivalents³—two ICRH antennas that are each ten times more powerful and 45 tonnes heavier.   Click here for a journal article on "Design and construction of the first ELM resilient long pulse ICRH antenna for WEST"   (¹) Lower hybrid resonance is another form of plasma heating which could be installed in °ÄÃÅÁùºÏ²Ê¸ßÊÖ as a future upgrade.(²) 10 MW/m² during 1000 s and 20 MW/m² during a few tens of seconds.(³) °ÄÃÅÁùºÏ²Ê¸ßÊÖ will be equipped with two 10 MW ICRH antennas (procured by Europe).

At °ÄÃÅÁùºÏ²Ê¸ßÊÖ, even the opening of a box takes on a spectacular dimension. The operation requires a powerful crane, a full team of specialists and, as everything °ÄÃÅÁùºÏ²Ê¸ßÊÖ, the utmost care and precision. The box-opening operation that unfolded on 13-14 June gave access to cryoplant equipment that had been sitting for several months in temporary storage—three 135-tonne "refrigerators" ("cold boxes") and their corresponding "warm panels."   But instead of removing the components from the boxes, the boxes were removed from the components—an operation that consisted in lifting the box tops (heavy wooden crates actually) that had served to protect the components during transport and storage.   Manufactured by the French company Air Liquide, the cold boxes contain the heat exchangers, turbines, valves, and filters that will cool and liquefy the large volumes of helium needed by cryogenic "clients" in the Tokamak Building (the magnets, thermal shield and cryopumps).   Composed of a complex arrangement of pipes, plugs, expansion valves, pressure and flow sensors, the role of the "warm panels" is to monitor and protect the processes inside the cold boxes. Gaseous helium enters a cold box at ambient temperature and comes out in liquid form at 4.5 K (minus 269 °C). All the processes that take place inside of the cold boxes are implemented under vacuum, in order to limit thermal exchange with the environment, and all components are wrapped in multilayer insulation blankets to protect from heat radiation.   To each cold box a "warm panel" is connected. Composed of a complex arrangement of pipes, plugs, expansion valves, pressure and flow sensors, its role is to monitor and protect the processes inside the cold boxes.   Now that they are free from their casing, the three cold boxes and their corresponding warm panels will be loaded on trailers to travel a few hundred metres to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ platform along the heavy haul road.   Once delivered to the cryoplant, they will be installed in the Cold Box Building, validating yet another °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council milestone*.   *A set of high-level schedule milestones has been proposed by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council as a way to measure and monitor project progress. "Start of work inside the cryoplant" was an °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council milestone scheduled for achievement before the end of Q2 2017.

On 14 June, the European Commission issued a Communication presenting the revised schedule and budget estimates for European participation in °ÄÃÅÁùºÏ²Ê¸ßÊÖ. Its object? To provide the necessary grounds to request the support of the European Parliament and a mandate from the Council of the European Union to approve the new baseline of the project on behalf of Euratom. Subtitled "The EU contribution to a reformed °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project," the 14-page document goes at length into the positive changes in project culture, schedule and cost control, risk management and mitigation, and design maturity that have been implemented since the arrival of the new °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General, Bernard Bigot, in March 2015.   These changes have contributed to a new impetus that has been confirmed by independent experts and by the seven project Members during meetings of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council.   As noted on pages 10-11 of the Communication: "A positive appreciation of the progress made both by the new °ÄÃÅÁùºÏ²Ê¸ßÊÖ management and the project itself has been confirmed by the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council Review Group that concluded in its report that the revision of the schedule was beneficial to the project and was conducted in a professional and robust manner. In addition the 2015 Management Assessment of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization also acknowledged effective efforts to make the project advance recognising management improvements, including in the decision making processes, as well as improved cooperation and integration of activities between the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and the Domestic Agencies. Overall the assessment affirmed that these changes were leading to an acceleration in the progress of the project."   At the Nineteenth Meeting of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council in November 2016 the Members endorsed an updated schedule for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project through First Plasma (2025) and Deuterium-Tritium Operation (2035). Corresponding overall project cost was approved ad referendum until each Member could seek approval of project costs through respective governmental budgeting processes.   For Europe the new schedule and its associated costs, backed up by the improvements in the project, provide the necessary grounds for the Commission to request the support of the European Parliament and a mandate from the Council of the EU to approve the new °ÄÃÅÁùºÏ²Ê¸ßÊÖ Baseline ad referendum on behalf of Euratom, most likely at a Ministerial level °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council meeting in 2017.   The Euratom approval needs to be ad referendum since the final Euratom contribution from the EU budget to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project and the other costs related to the activities of Fusion for Energy and to the management of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project will be subject to the Commission's proposals and outcome of negotiations on Brexit and the next Multiannual Financial Framework post 2020. (The current Multiannual Financial Framework caps the European Union contribution to the construction budget for °ÄÃÅÁùºÏ²Ê¸ßÊÖ at EUR 6.6 billion in 2008 values, up to 2020.)   The Communication issued on 14 June specifies the resources needed for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ construction after 2020 under the updated baseline.   Click here to open the European Commission press release titled "Fusion as an energy source: the °ÄÃÅÁùºÏ²Ê¸ßÊÖ project is back on track." (The full 14-page Communication can be downloaded from the press release.)   A report is also available on the website of the European Domestic Agency.

Excitement was tangible among the invited guests and journalists when Olzhas Suleimenov, one of the most influential and respected poets and writers in modern Kazakhstan, visited the French pavilion and the °ÄÃÅÁùºÏ²Ê¸ßÊÖ exhibition at EXPO 2017 Astana last Friday 16 June. Initiator of the Nevada-Semipalatinsk movement, which campaigned to close nuclear testing sites in Kazakhstan and the US, former Ambassador to Rome, and Ambassador to UNESCO for the Kazakh government from 2001 to 2014. Suleimenov spoke with °ÄÃÅÁùºÏ²Ê¸ßÊÖ Newsline on fusion and °ÄÃÅÁùºÏ²Ê¸ßÊÖ.   It is a great honour to be here with you today. What brought you to visit the °ÄÃÅÁùºÏ²Ê¸ßÊÖ exhibition at EXPO 2017?   I was invited to visit many pavilions at the EXPO, but it was a particular wish to visit the French Pavilion. I know France and its capabilities very well. It was interesting for me to see how the problems that we are all concerned with are being approached currently.   I was very happy to see the stand of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project, which proposes the important project of bringing the energy of the Sun to Earth. I agree with the idea behind this project because homo sapiens initially used the energy of the Sun and realized its importance in supporting life on Earth.    It is wonderful that this international project involves the efforts of many scientists and engineers from different countries. As an engineer and geologist I understand that this kind of project requires decades of work. It is possible that many decades will be needed before we have this source of energy, which will save us from using coal, oil, hydrogen and nuclear technologies that are harmful for the human race. That is why I was happy to see that this kind of project is underway; it will certainly attract the attention of our local specialists. I will be talking about the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project here in Kazakhstan and not only. Your movement was instrumental in stopping nuclear tests at the Semipalatinsk site in Kazakhstan, yet you are supportive of this new nuclear technology called fusion?   Certainly. Nuclear fission will continue to be needed until we develop an alternative solution. Our Nevada-Semipalatinsk movement has been putting all its effort for more than twenty years into stopping any initiative to develop nuclear energy at an industrial level here in Kazakhstan, even though our country is one of the main producers of uranium. We believe that we can develop and use other sources of energy such as wind, solar power, etc. and wait the moment when nuclear fusion works.   If the scientists and engineers manage to do this, then we will have the possibility of using a safe nuclear energy technology that won't damage nature for centuries. Fusion technology does not produce highly irradiated, long-life nuclear waste. That is why fusion energy needs to be developed as soon as possible, as humanity's solution for the future.   Are you aware that Kazakhstan signed a technical Cooperation Agreement with °ÄÃÅÁùºÏ²Ê¸ßÊÖ recently? There now will be the possibility for exchanges between scientists on very advanced technology ...    I didn't know, but I am very happy to hear that. It is very important for Kazakhstan and I hope that it is the same for the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project. In the Kazakh language "°ÄÃÅÁùºÏ²Ê¸ßÊÖ" (kaz: итер) means "to push"—only a small detail but one that, as a writer, I pay attention to. This project has to push the boundaries of science and technology in order to realize as soon as possible plans for our future energy mix—plans that could help to save humanity.   [Interview edited for brevity.]

For fusion to generate substantial energy, the ultra-hot plasma that fuels fusion reactions must remain stable and kept from cooling. Researchers have recently shown lithium, a soft, silver-white metal, to be effective in both respects during path-setting US-Chinese experiments on the Experimental Advanced Superconducting Tokamak (EAST) in Hefei, China. Seven US researchers traveled to EAST in December, 2016, to participate in the experiments. They deployed lithium in the Chinese tokamak in three different ways: through a lithium powder injector, a lithium granule injector, and a flowing liquid lithium limiter (FLiLi) that delivered the element in liquid form to the edge of EAST plasmas. Good results were shown by all three techniques. Leading the US collaboration is the US Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), together with co-principal investigators Los Alamos and Oak Ridge National Laboratories, with Johns Hopkins University, the University of Illinois at Urbana-Champaign, the University of Tennessee-Knoxville, and the Massachusetts Institute of Technology. Scientists from General Atomics also participate via a separate grant. -- John Greenwald, PPPL See the full report on the PPPL website.

It is with great regret that the °ÄÃÅÁùºÏ²Ê¸ßÊÖ community has learned of the sudden passing of Professor Predhiman Krishan Kaw on 18 June. Professor Kaw was a well-known and highly respected plasma physicist, author of over 380 research publications in scientific journals. He was the founding director of the Institute for Plasma Research in Gujarat, India, which he led from 1986 to 2012. Named Year of Science Chair by the Indian Department of Science & Technology (DST), Professor Kaw continued to be active in research and in the mentoring and training of the younger generation of plasma physicists as DST Professor at the Institute for Plasma Research. Professor Kaw was also the first Chair of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council Science and Technology Advisory Committee (STAC), leading the committee's deliberations from 2007 to 2009, and a regular participant to °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council meetings as Representative of India. For his outstanding contributions to experimental and/or theoretical research in fundamental plasma physics and plasma applications, he was awarded the prestigious Padma Shri award (India's fourth highest honour) in 1985; the Shanti Swarup Bhatnagar Prize for Science and Technology in 1986; the World Academy of Sciences (TWAP) Prize in 2008; and the Subrahmanyan Chandrasekhar Prize of Plasma Physics in 2016 (see related article in Newsline). See the Institute for Plasma Research website for more information. Professor Predhiman Krishan Kaw (2nd from left) is seen here on 21 November 2014 at the inauguration of the Cryostat Workshop, where India is assembling the °ÄÃÅÁùºÏ²Ê¸ßÊÖ cryostat. With him are the former °ÄÃÅÁùºÏ²Ê¸ßÊÖ Director-General Osamu Motojima; M.V. Kotwal, president of Larsen & Toubro's Heavy Engineering Division; and Shishir P. Deshpande, Head of the Indian Domestic Agency.