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detrit tank install 4 small ed Like a lunar module checking its landing coordinates one last time, the cylindrical tank with six metal feet hovered silently over the Tritium Building. The event was significant. Part of ITER's water detritiation plant system, the tank had the honour of being the first component to be installed in the Tokamak Complex.

Both a "captive component" (once installed, it cannot be removed) and a Protection Important Component (PIC), the holding tank that was lowered into the Tritium Building on the morning of Tuesday 29 March is part of a set of four that will play a key part in the detritiation process of the ITER installation.

In the Tokamak Building, tritium needs to be removed from the atmosphere of different "spaces" such as the vacuum vessel, the port cells, the neutral beam injector, etc.

Tritiated air is extracted and passed through a shower (the "scrubber columns") to become tritiated water, which is stored in holding tanks. Following storage, the tritiated water is submitted to electrolysis to recuperate the highly valuable tritium in the ITER fuel cycle.

Three years ago the design of the tanks was launched and progressed in parallel with the design of the finer details of the Tritium Building—such as defining the precise position of the anchors for the tanks. As interfaces perfectly locked into place, Tuesday's operation marked an important and symbolic moment in the progress of construction.

Source: ITER newsline

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First plasma w7x A successful start with helium plasma / hydrogen plasma to follow at the beginning of 2016.

On 10th December 2015 the first helium plasma was produced in the Wendelstein 7-X fusion device at the Max Planck Institute for Plasma Physics (IPP) in Greifswald. After more than a year of technical preparations and tests, experimental operation has now commenced according to plan. Wendelstein 7-X, the world’s largest stellarator-type fusion device, will investigate the suitability of this type of device for a power station.

Following nine years of construction work and more than a million assembly hours, the main assembly of the Wendelstein 7-X was completed in April 2014. The operational preparations have been under way ever since. Each technical system was tested in turn, the vacuum in the vessels, the cooling system, the superconducting coils and the magnetic field they produce, the control system, as well as the heating devices and measuring instruments. On 10th December, the day had arrived: the operating team in the control room started up the magnetic field and initiated the computer-operated experiment control system. It fed around one milligram of helium gas into the evacuated plasma vessel, switched on the microwave heating for a short 1,3 megawatt pulse – and the first plasma could be observed by the installed cameras and measuring devices. “We’re starting with a plasma produced from the noble gas helium. We’re not changing over to the actual investigation object, a hydrogen plasma, until next year,” explains project leader Professor Thomas Klinger: “This is because it’s easier to achieve the plasma state with helium. In addition, we can clean the surface of the plasma vessel with helium plasmas.”

The first plasma in the machine had a duration of one tenth of a second and achieved a temperature of around one million degrees. “We’re very satisfied”, concludes Dr. Hans-Stephan Bosch, whose division is responsible for the operation of the Wendelstein 7-X, at the end of the first day of experimentation. “Everything went according to plan.” The next task will be to extend the duration of the plasma discharges and to investigate the best method of producing and heating helium plasmas using microwaves. After a break for New Year, confinement studies will continue in January, which will prepare the way for producing the first plasma from hydrogen.

Background

The objective of fusion research is to develop a power source that is friendly to the climate and, similarly to the sun, harvests energy from the fusion of atomic nuclei. As the fusion fire only ignites at temperatures of more than 100 million degrees, the fuel – a thin hydrogen plasma – must not come into contact with cold vessel walls. Confined by magnetic fields, it floats virtually free from contact within the interior of a vacuum chamber. For the magnetic cage, two different designs have prevailed – the tokamak and the stellarator. Both types of system are being investigated at the IPP. In Garching, the Tokamak ASDEX Upgrade is in operation and, as of today, the Wendelstein 7-X stellarator is operating in Greifswald.

At present, only a tokamak is thought to be capable of producing an energy-supplying plasma and this is the international test reactor ITER, which is currently being constructed in Cadarache in the frame of a worldwide collaboration. Wendelstein 7-X, the world's largest stellarator-type fusion device, will not produce energy. Nevertheless, it should demonstrate that stellarators are also suitable as a power plant. Wendelstein 7-X is to put the quality of the plasma equilibrium and confinement on a par with that of a tokamak for the very first time. And with discharges lasting 30 minutes, the stellarator should demonstrate its fundamental advantage – the ability to operate continuously. In contrast, tokamaks can only operate in pulses without auxiliary equipment.

The assembly of Wendelstein 7-X began in April 2005: a ring of 50 superconducting coils, some 3.5 metres high, is the key part of the device. Their special shapes are the result of refined optimisation calculations carried out by the “Stellarator Theory Department”, which spent more than ten years searching for a magnetic cage that is particularly heat insulating. The coils are threaded onto a ring-shaped steel plasma vessel and encased by a steel shell. In the vacuum created inside the shell, the coils are cooled down to superconduction temperature close to absolute zero using liquid helium. Once switched on, they consume hardly any energy. The magnetic cage that they create, keeps the 30 cubic metres of ultra-thin plasma – the object of the investigation – suspended inside the plasma vessel.

The investment costs for Wendelstein 7-X amount to 370 million euros and are being met by the federal and state governments, and also by the EU. The components were manufactured by companies throughout Europe. Orders in excess of 70 million euros were placed with companies in the region. Numerous research facilities at home and abroad were involved in the construction of the device. Within the framework of the Helmholtz Association of German Research Centres, the Karlsruhe Institute of Technology was responsible for the microwave plasma heating; the Jülich Research Centre built measuring instruments and produced the elaborate connections for the superconducting magnetic coils. Installation was carried out by specialists from the Polish Academy of Science in Krakow. The American fusion research institutes at Princeton, Oak Ridge and Los Alamos contributed equipment for the Wendelstein 7-X that included auxiliary coils and measuring instruments.

Source: Max Planck Institute for Plasma Physics

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W7 X June 2015 Next week: start with helium plasma planned / hydrogen plasmas are to follow in 2016

With the generation of the first plasma the Wendelstein 7-X fusion device is scheduled to go into operation on time in December 2015 at the Max Planck Institute for Plasma Physics (IPP) in Greifswald/Germany. The experiments will begin with a plasma consisting of the noble gas helium. The Wendelstein 7-X fusion device is the world’s largest and most advanced device of the stellarator type. Its objective is to investigate the suitability of this type for a power plant.

After nine years of construction and more than one million installation hours the main assembly of Wendelstein 7-X was completed in April 2014. Since then, preparations for operation have been conducted. One by one the technical systems have been tested – the vacua in the cryostat and the plasma vessel, the cooling system, the superconducting coils and the magnetic field produced by them, the control system as well as the heating and measurement devices.

Subject to the operating licence being granted, the first plasma has been scheduled for 10 December 2015. “We will start with a plasma of the noble gas helium and change, next year, to the actual object of investigation, a hydrogen plasma“, states Project Head Professor Thomas Klinger: “In helium the plasma state is easier to achieve. Moreover, we can use the helium plasmas to clean the surface of the plasma vessel.“ The first hydrogen plasma will follow at the end of January 2016.

Background

The objective of fusion research is to develop a power plant favourable to the climate and environment that derives energy from the fusion of atomic nuclei just as the sun and the stars do. Since the fusion fire only ignites at temperatures over 100 million degrees, the fuel, viz. a low-density hydrogen plasma, ought not to come into contact with the cold walls. Confined by magnetic fields, the fuel is suspended almost free of contact inside a vacuum chamber. For the magnetic cage, two different designs have prevailed, the tokamak and the stellarator. Both of these device types are being investigated by IPP. The ASDEX Upgrade tokamak is being operated at IPP Garching, the Wendelstein 7-X stellarator is located at IPP Greifswald.

Today, only a tokamak such as the ITER international test reactor is trusted to produce an energy-supplying plasma. Also Wendelstein 7-X, the largest stellarator-type fusion device in the world, will not produce energy. However, the plant is expected to prove the suitability of the stellarator concept for a power station. Wendelstein 7-X is expected to put, for the first time, the quality of plasma equilibrium and confinement on an equal footing with those of a tokamak. And with discharges lasting up to 30 minutes, it should demonstrate the main advantage of stellarators, their ability to operate continuously. In contrast, tokamaks without auxiliary facilities operate in pulsed mode.

Assembly of Wendelstein 7-X began in April 2005: A ring of 50 superconducting magnetic coils approximately 3.5 metres in height, is the key component of the device. Their special shapes are the result of refined optimisation calculations made by the Stellarator Theory division, over a ten year period. The resulting shapes provide a magnetic cage for the plasma with particularly good thermal-insulation properties. The coils are strung along a steel plasma vessel and are enclosed in a ring-shaped steel shell. In its vacuum-pumped interior, the magnets are cooled with liquid helium to superconduction temperature at nearly absolute zero. They then hardly consume any energy. The magnetic field cage generated by them inside the plasma vessel is confining the object of research, the 30 cubic meter of ultra-thin plasma.

The investment costs met by the Federal Government, the State of Mecklenburg-Western Pomerania and the EU added up to 370 million euros. Contracts worth more than 70 million euros were awarded to regional companies. Companies from the whole of Europe produced the components for Wendelstein 7-X. Numerous research facilities at home and abroad were involved in the construction of the device: Within the framework of Helmholtz Association the Karlsruhe Institute of Technology was responsible for the entire microwave plasma heating and the Jülich Research Centre built diagnostics and produced the elaborate connections of the superconducting magnet coils. Specialists from the Polish Academy of Sciences in Krakow carried out their installation. The US fusion institutes at Princeton, Oak Ridge, and Los Alamos made contributions that included auxiliary coils and measuring instruments for equipping Wendelstein 7-X.

Source: Max-Planck-Institute fur Plasmaphysik

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JET Conceptual Design In fusion reactor designs, superconductors (which suffer no resistive power loss) are used to generate the magnetic fields that confine the 100 million degree C plasma. While increasing magnetic field strength offers potential ways to improve reactor performance, conventional low-temperature superconductors suffer dramatic drops in current carrying ability at high magnetic fields. Now, the emergence of high-temperature superconductors that can also operate at high magnetic fields opens a new, lower-cost path to fusion energy.

A typical measure of fusion plasma performance is called "plasma beta," which is the ratio of plasma pressure to magnetic field pressure. Achieving a very high beta--generating the required plasma pressure with low magnetic field--could help reduce the cost of the superconducting magnets used in a fusion reactor. For this reason, many visions of fusion reactors try to maximize plasma beta at moderate magnetic field strengths. Operation at higher beta, however, pushes the plasma up against many performance limits, making plasma stability a tricky business.

But plasma beta is not the only consideration. Another ratio, the size of the confined plasma compared to the ion gyroradius, also determines overall energy confinement and dictates plasma performance. (The ion gyroradius is the helical path ions are forced to follow in the magnetic field.) Increasing magnetic field strength decreases the ion gyroradius, which allows a reduction in the size of the fusion device with no loss of performance. This approach also lowers beta and the plasma operates farther away from stability limits, in a "safe zone."

While scientists have explored both of these paths to improving performance, the recent development of the so-called "high-temperature superconductors" opens a window for much higher magnetic fields, as the critical currents do not degrade rapidly, even at magnetic field values of 30 Tesla or higher. So these should really be called high-temperature, high-magnetic-field superconductors.

For tokamak design, the field strength limits are primarily determined by the maximum allowable stresses in the structural components holding the magnet together, and not by the intrinsic limits of the superconductors.

Even the most aggressive tokamak designs with conventional superconductor technology are limited to about 6 Tesla on-axis toroidal magnetic fields. By nearly doubling magnetic field strength, to about 10 Tesla on-axis, conceptual designs indicate that a tokamak approximately the physical size of the world's largest currently operating tokamak, JET, would be capable of producing 500 MW of fusion power, and even net electricity (Figure 1). High-temperature, high-magnetic-field superconductors can also make it possible to incorporate jointed magnetic coils into the reactor design, dramatically improving flexibility, and ultimately, maintainability for reactor systems.

While several physics and technology challenges remain to be solved, the world-wide experience from tokamak experiments provides the basis to support a new path of exploration into compact, power producing reactors using the newly available high-temperature, high-magnetic-field superconducting technology.

Source: American Physical Society via EurekAlert

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F4E Schwemmer Director web 2-211020151200-Large Johannes Schwemmer has been appointed Executive Director of Fusion for Energy, the European Joint Undertaking for ITER and the Development of Fusion Energy.

Joaquin Sánchez, Chair of the Fusion for Energy Governing Board, thanked all members for their collaboration in taking this important decision and congratulated Johannes Schwemmer on his new position. “We look forward to working with you and offering our guidance so that Europe honours its commitment in the various projects that aim to bring fusion energy closer” he stated.

"It is a great honour to be appointed Director of Fusion for Energy and to serve this organisation with leadership, loyalty and vision. I’m fully committed to managing effectively the European contribution to ITER, this unique global collaboration that has the ambition to make fusion a viable option for abundant and clean base load energy supply” Schwemmer said.

Johannes Schwemmer has been working in the fields of information, telecommunications and business technology for more than 25 years. He has a proven track record in international collaboration, project management and business strategy. He is currently a partner at Antevorte, a German consultancy specialising in performance management. Previously he worked for eight years at Unify GmbH & Co. KG, a global market leader in unified communication solutions present in 100 countries, where he held different positions as Vice-President for Global Project Management and Service Optimisation, and Vice-President for Global Training. Earlier in his career he worked at Siemens Business Services, as Vice-President for Risk Management and Strategic Alliances Management. He holds a European Joint Degree in Electrical Engineering from the University of Karlsruhe (KIT), Germany, in collaboration with the University of Essex, UK and ESIEE Paris, France.

The Director is appointed by Fusion for Energy’s Governing Board for a period of five years, once renewable up to five years. The appointment is made on the basis of a list of candidates proposed by the European Commission after an open competition, following a publication in the Official Journal of the European Communities.

Fusion for Energy
Fusion for Energy (F4E) is the European Union’s organisation for Europe’s contribution to ITER.
One of the main tasks of F4E is to work together with European industry, SMEs and research organisations to develop and provide a wide range of high technology components together with engineering, maintenance and support services for the ITER project.
F4E supports fusion R&D initiatives through the Broader Approach Agreement signed with Japan and prepares for the construction of demonstration fusion reactors (DEMO).
F4E was created by a decision of the Council of the European Union as an independent legal entity and was established in April 2007 for a period of 35 years. Its offices are in Barcelona, Spain.
www.fusionforenergy.europa.eu

ITER
ITER is a first-of-a-kind global collaboration. It will be the world's largest experimental fusion facility and is designed to demonstrate the scientific and technological feasibility of fusion power.
Fusion is the process which powers the sun and the stars. When light atomic nuclei fuse together to form heavier ones, a large amount of energy is released. Fusion research is aimed at developing a safe, limitless and environmentally responsible energy source.
Europe will contribute almost half of the costs of its construction, while the other six Members to this joint international venture (China, Japan, India, the Republic of Korea, the Russian Federation and the USA), will contribute equally to the rest. The site of the ITER project is in Cadarache, in the South of France.
www.iter.org/

Source: F4E

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