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The latest podcast from Decrypted by Bloomberg starts with the question: "How close are we to realizing the silver bullet for clean, cheap and abundant energy ... fusion?"

Featuring lengthy interviews at the US Department of Energy's largest science and energy laboratory, the Oak Ridge National Laboratory in Tennessee, journalists Jing Cao and Aki Ito delve into the way nuclear fusion fuels our Sun and stars and how scientists plan to make it commercially viable on Earth, despite a lack of funding ...

Follow the 25-minute podcast "The Nuclear Tech Breakthrough That Could Make Oil Obsolete" here. 

Physicist Fatima Ebrahimi from the Princeton Plasma Physics Laboratory (PPPL) has for the first time used advanced models to accurately simulate key characteristics of the cyclic behaviour of edge-localized modes (ELMs), a particular type of plasma instability.

The findings could help physicists more fully comprehend the behaviour of plasma, the hot, charged gas that fuels fusion reactions in doughnut-shaped fusion facilities called tokamaks, and more reliably produce plasmas for fusion reactions. The findings could also provide insight into solar flares, the eruptions of enormous masses of plasma from the surface of the sun into space.

ELMs occur around the outer edge of high-confinement, or H-mode, plasmas due to strong edge currents. Ebrahimi used a computer simulation code known as NIMROD to show how ELMs go through a repeated cycle in which they form, develop, and vanish.

The model demonstrates that ELMs can form when a steep gradient of current exists at the plasma edge. The gradient develops when the plasma moves suddenly up or down, creating a bump in the current and forming an edge current sheet. The instability then forms a current-carrying filament that moves around the tokamak, producing electrical fields that interfere with the currents that caused the ELMs to form. With the original currents disrupted, the ELM dies. "In a way," Ebrahimi said, "an ELM eliminates its own source — erases the bump on the edge current — by its own motion."

Ebrahimi's findings are consistent with observations of cyclic behaviour of ELMs in tokamaks around the world. These include Pegasus, a small spherical device at the University of Wisconsin; the Mega Ampere Spherical Tokamak (MAST) in the United Kingdom; and the National Spherical Torus Experiment (NSTX), the flagship facility at PPPL before its recent upgrade. The research could also improve understanding of solar eruptions, which are accompanied by filamentary structures similar to those produced by ELMs. Her next step will involve investigating the impact of differences in plasma pressure on the cyclic behaviour of ELMs.

Read the full article on the PPPL website.

The elements of the ITER divertor that will directly face the hot plasma must withstand a heat load that is estimated at ten times that of a spacecraft re-entering Earth's atmosphere.

Procuring parties Russia (divertor dome), Japan (divertor outer targets) and Europe (divertor inner targets) are all engaged in multiyear qualification programs that include prototype fabrication and high heat flux testing.

The European Domestic Agency made the choice of contracting with three separate manufacturers for the development of small-scale inner vertical target prototypes that are 1/19th of the actual scale needed for ITER. In the first stage of the pre-qualification program the prototypes were successfully tested in high heat flux conditions; the next step will now be to develop full-scale prototypes. This phase—which involves the three manufacturers plus a fourth, pre-qualified supplier—is expected to last approximately three years.

Read the full article on the European Domestic Agency website.

We have learned with profound sadness of the passing of Dr Yasuo Shimomura, who served as ITER Deputy Director from the beginning of the Engineering Design Activities (EDA) in 1992 until 2001. From 2001 until 2003 Dr Shimomura was ITER International Team Co-Leader, and from 2003 until 2005 he was ITER Interim Project Leader; during this last period he led the ITER team through the difficult transitional phase from the design activity to the start of construction in 2006.

A graduate of Osaka University, Dr Shimomura had a distinguished career in fusion research at the Japan Atomic Energy Research Institute, JAERI (now part of the National Institutes for Quantum and Radiological Science and Technology, QST). He was a leading figure in the construction and operation of the JFT-2a/DIVA tokamak, developing a reactor-relevant divertor concept that is currently being applied to ITER. He was also Leader of the JT-60 Experimental Planning and Analysis Group, and in 1986 was appointed as Head of the Large Tokamak Experiment Division at JAERI, with overall responsibility for the JT-60 tokamak. From 1988 he combined the leadership of the JT-60 device and its conversion to JT-60U with an appointment as Head of the Poloidal Field Design Group within the ITER Conceptual Design Activities (CDA). He was appointed ITER Deputy Director within the ITER EDA in July 1992, with responsibility for the design integration of the project. Dr Shimomura also held guest scientist positions at Princeton Plasma Physics Laboratory from 1976 to 1977 and at the Max-Planck-Institut für Plasmaphysik in Garching from 1981 to 1982.

Dr Shimomura will be remembered by his many friends and colleagues in the ITER community as a gifted physicist who contributed greatly to the project during an involvement spanning 20 years. He will be greatly missed by all who knew him and who benefitted from his leadership and guidance.

In ITER, six technological solutions for tritium breeding—in the form of test blanket modules plus associated ancillary systems—will be operated and tested for the first time. Their experimental validation will represent a major step for fusion development beyond ITER, when tritium fuel will necessarily have to be bred within the reactor.

In China, Europe, India, Japan and Korea these solutions are under development, with Russia and the United States contributing R&D and providing general support for the test blanket module program.

Europe is developing two types of test blanket modules, which consist of a steel box containing tritium breeders, neutron multiplier materials and heat extraction plates. Over the past two years, the European Domestic Agency and industrial partners have been manufacturing mockups of these boxes to test welding techniques. A preliminary welding procedure, employing a tungsten inert gas (TIG) welding robot to carry out the tasks within the limited space of the box, has been identified. The welding qualification cycle is expected to end within the next two years.

See the full article on the European Domestic Agency website.

Edmund Synakowski—the Associate Director of the US Department of Energy (DOE) Office of Fusion Energy Sciences and former ITER Council Vice-Chair—has been chosen as the University of Wyoming's vice president for research and economic development. Synakowski will also be a professor in the university's Department of Physics and Astronomy.

The role of the vice president for research and economic development is to support and facilitate the research efforts of University of Wyoming's faculty, staff and students; direct the university's research mission as a public research university; promote the university's research program with stakeholders; and direct technology transfer and commercialization efforts for the university's intellectual property.

Synakowski has held his current position, associate director of science in the Department of Energy, since 2009, administering a budget of about $400 million annually to develop nuclear fusion as an energy source. His agency supports research at more than 50 universities, eight national and two federal laboratories, and 15 industry groups.

He previously led the Fusion Energy Program at the Lawrence Livermore National Laboratory in California and held a number of roles at Princeton University's Plasma Physics Laboratory.

Read the full report on the University of Wyoming's website here.