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Convening for an Extraordinary Meeting in Paris on 27 April, the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council received the assessment of the Independent Review Group and discussed its findings. The high-level representatives of the seven °ÄÃÅÁùºÏ²Ê¸ßÊÖ Members acknowledged the external validation of the project's progress, declaring that the findings confirmed "that the project is now going in the right direction, in a way that will allow for a sound, realistic and detailed proposal for schedule and associated cost up to First Plasma."   The proposal will be tabled for the regular meeting of the Council in June.   Among the key findings that the Extraordinary Council was pleased to note are: "substantial improvement in project performance" resulting from the major restructuring of °ÄÃÅÁùºÏ²Ê¸ßÊÖ; the quality of "the preparation of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and Domestic Agencies on a new schedule and associated resource estimate"; and the efficiency of the "ongoing additional integration work" being carried out project wide.   The Extraordinary °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council acknowledged that these "converging elements" provided a solid basis for the establishment of the Resource-Loaded Updated Integrated Schedule up to First Plasma along with a high-level paper detailing the schedule from First Plasma to Deuterium-Tritium operation in time for submission to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council in June 2016 (IC-18).   Read the press release from the Extraordinary °ÄÃÅÁùºÏ²Ê¸ßÊÖ Council in English or in French.

Two separate electrical networks will distribute power throughout the °ÄÃÅÁùºÏ²Ê¸ßÊÖ installation—the steady state electrical network (SSEN) that will bring down the high-tension grid voltage from 400 kV to the standard 20 kV of industrial facilities, and the pulsed power electrical network (PPEN) that will feed power to the heating and control systems during plasma pulses.   The first is standard for industrial installations; the second is specific to fusion machines which require a substantial input of electrical power for brief periods of time.   When °ÄÃÅÁùºÏ²Ê¸ßÊÖ reaches the deuterium-tritium operation phase, the instantaneous power consumption during pulses will be in the range of 450 MW, or about half the output of a conventional nuclear reactor.   Four SSEN transformers procured by the US as part of its in-kind contributions to °ÄÃÅÁùºÏ²Ê¸ßÊÖ, are now installed on the °ÄÃÅÁùºÏ²Ê¸ßÊÖ platform.   These rather heavy components weigh close to 90 tonnes, for the main body, and almost twice as much when filled with insulating oil and fitted with all their accessories.   However large and heavy, they will be dwarfed by their soon-to-be neighbours that will tower some 15 metres above ground (with all insulators extended). The three PPEN transformers that are expected soon from China are massive structures that will weigh approximately 460 tonnes each when completely filled and fitted out.   Procured by the Chinese Domestic Agency, the first of the three units left the port of Tianjin on 17 April and is expected on site in early June. The other two are undergoing factory tests at manufacturer Baoding Tianwei.   Leaving for a long journey. Transformer #1 left Tianjin on 17 April and is expected on site in early June.

Shortly before dawn on Tuesday 26 April, concrete pouring began on the B1 level basemat of the Tokamak Building.    Some 540 cubic meters of concrete were employed in filling a 750 square-metre area (plots 4 and 5) in the southeast corner of the Tokamak Pit.   The operation was of special significance, as the B1 level is host to 18 port cells and one strategic equipment element — the cask transfer system, part of the remote handling system for the divertor cassettes assemblies.   Pouring operations will resume in a fortnight.

With the signature in April of a final Complementary Diagnostic Procurement Arrangement with the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization, the Russian Domestic Agency has now formalized the procurement of its complete in-kind scope—two dozen work packages in all that define the equipment for °ÄÃÅÁùºÏ²Ê¸ßÊÖ that is under Russian responsibility.   The Complementary Diagnostic Procurement Arrangement signed on 14 April by Anatoly Krasilnikov, the head of the Russian Domestic Agency, and Eisuke Tada, °ÄÃÅÁùºÏ²Ê¸ßÊÖ Deputy Director-General, covers the fabrication and delivery of the diagnostic equipment that will be integrated into lower port #8. This includes the required structures and services for the integration, installation and operation of three diagnostics: the erosion monitor, divertor Thomson scattering, and laser induced fluorescence.   The function of these structures is to accurately position and align the diagnostic systems in the °ÄÃÅÁùºÏ²Ê¸ßÊÖ machine and to provide structural integrity to withstand the harsh conditions inside of the vacuum vessel at maximum machine performance. Last but not least, they will provide neutron shielding to guarantee that radiation doses are kept below the established limits in areas where human access is required.   The diagnostic equipment will be installed inside of a support structure called a diagnostic rack, a stainless steel structure measuring 4 metres and weighing 10 tonnes. It will be fully remote handling compatible and connected to the main services such as cooling, gas and electrical supplies. Other equipment covered in the Complementary Diagnostic Procurement Arrangement are ex-vessel structures such as interspace and port cell support structures.   With this final signature, all Russian contributions to the project are now in the hands of industry.

A major °ÄÃÅÁùºÏ²Ê¸ßÊÖ procurement milestone was recorded in April by the European Domestic Agency, as contractors completed the first 110-tonne toroidal field winding pack. The winding pack, or D-shaped inner core, will now be cold tested at -200 °C/80 K before being inserted into a massive stainless steel case to form a final toroidal field coil assembly measuring 9 x 17 metres and weighing 310 tonnes. Work is already underway on the assembly of a second winding pack at ASG Superconductors in La Spezia, Italy.   In °ÄÃÅÁùºÏ²Ê¸ßÊÖ 18 toroidal field magnets—each made up of a winding pack and stainless steel coil case—will surround the vacuum vessel to produce the powerful magnetic field that will confine the particles of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ plasma. Europe has the procurement responsibility for half the coils plus one spare; Japan is producing nine coils and all stainless steel coil cases.   For Alessandro Bonito-Oliva, Europe's manager for magnets, "This is a landmark achievement for the whole project. We have been working really hard to meet the tight planning and manage all interfaces so that all pieces come together at the right time. The very good collaboration between the teams of the European Domestic Agency, the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization and the Japanese Domestic Agency has helped us to reach this point and go beyond as production accelerates."   To produce the first toroidal field winding pack, European contractors Iberdrola (Spain), ASG Superconductors (Italy), and Elytt Energy (Spain) collaborated closely with radial plate manufacturers CNIM and SIMIC. The step-by-step process included the winding of cable-in-conduit, niobium-tin-based superconductors into flat spirals called double pancakes, insertion into radial plates, impregnation with epoxy resin, and finally the stacking, jointing, wrapping, and full electrical insulation of seven double pancakes to form the final winding pack. Europe estimates that more than 600 people from at least 26 companies have contributed to this milestone.

A senior researcher at MIT's Plasma Science and Fusion Center (PSFC) in the US is using a gyrotron, a specialized radio-frequency (RF) wave generator developed for fusion research, to explore how millimetre RF waves can open holes through hard rock by melting or vaporizing it. Penetrating deep into rock is necessary to access virtually limitless geothermal energy resources, to mine precious metals or explore new options for nuclear waste storage. But it is a difficult and expensive process, and today's mechanical drilling technology has limitations. Woskov believes that powerful millimetre-wave sources could increase deep hard rock penetration rates by more than ten times at lower cost over current mechanical drilling systems, while providing other practical benefits. "There is plenty of heat beneath our feet," he says, "something like 20 billion times the energy the world uses in one year." But, Woskov notes, most studies of the accessibility of geothermal energy are based on current mechanical technology and its limitations. They do not consider that a breakthrough advance in drilling technology could make possible deeper, less expensive penetration, opening into what Woskov calls "an enormous reserve of energy, second only to fusion: base energy, available 24/7." Current rotary technology is a mechanical grinding process, limited by rock hardness, deep pressures, and high temperatures.  Specially designed "drilling mud," pumped through the hollow drill pipe interior, is used to enable deep drilling and to remove the excess cuttings, returning them to the surface via the ring-shaped space between the drill pipe and borehole wall. The pressure of the mud also keeps the hole from collapsing, sealing and strengthening the hole in the process. But there is a limit to the pressures such a borehole can withstand, and typically holes cannot be drilled beyond 30,000 feet (9km). Woskov asks, "What if you could drill beyond this limit? What if you could drill over ten kilometers into the earth's crust?" With his proposed gyrotron technology this is theoretically possible. Continue reading on the PSFC website.

The ASDEX-Upgrade team at the Max Planck Institute for Plasma Physics (IPP) in Garching, Germany is experimenting with a new mode of tokamak operation. In recent experimental results, an operational mode described as offering "stable plasma, high plasma pressure and good confinement properties in a parameter range in which future power plants are to be working" has been achieved almost without the transformer, or solenoid, that is typically used to induce the strong current in the plasma that contributes to creating the magnetic cage of tokamaks like °ÄÃÅÁùºÏ²Ê¸ßÊÖ and ASDEX-Upgrade. In its place, microwaves and particle beams injected close to the plasma core were used to prolong the plasma pulse. This type of "advanced tokamak operation" was the object of investigation for IPP scientist Alexander Bock, who details the advantages that continuous operation would have over pulsed operation as part of his PhD thesis. Advantages included better control of the plasma current profile in the plasma, longer pulses, and decreased turbulence. Read the IPP press release in English or in German.