The cooling pipes that snake along the surface of the vacuum vessel thermal shield will be removed and replaced. Here, on a right-hand outboard panel, workers determine the impact of pipe removal on the surface of the component. (Photo: ITER Organization)
ITER’s machine assembly phase began about two and a half years ago. Now, staff are reversing some of that assembly work to make needed repairs. According to a news article published by the ITER Organization on January 9, ITER is “facing challenges common to every industrial venture involving first-of-a-kind components.” Over one year after problems were first detected and less than two months after they were made public in late November, tests and analysis are producing a clearer picture of necessary repairs to the tokamak’s thermal shield panels and vacuum vessel sectors.
“There is no scandal here,” said ITER director general Pietro Barabaschi. “Such things happen. I've seen many issues of the kind, and much worse.”
A total of about 23 kilometers (about 14 miles) of piping are welded to the surface of the thermal shield panels. The piping on a vacuum vessel thermal shield panel is clearly visible in this photo. (Photo: ITER Organization)
The ITER Organization is working on a new baseline schedule for the magnetic confinement fusion experiment launched in 1985 and now under construction in southern France. First plasma was scheduled for December 2025 and deuterium-tritium operations for 2035 under a schedule approved in November 2016 that will soon be shelved. In addition to impacts from COVID-19 delays and uncertainty resulting from Russia’s war in Ukraine, ITER leaders must now factor in repair time for “component challenges.”
The Spherical Tokamak for Energy Production, shown here in an artist's rendition, is a government-backed prototype fusion energy plant planned for operation in the U.K. in the early 2040s. (Image: UKAEA)
The U.K. Atomic Energy Authority (UKAEA) and Tokamak Energy announced on October 10 that they signed a framework agreement to collaborate on developing spherical tokamaks for power production. This news is a complement to last week’s announcement from the U.K. government that the West Burton A coal-fired power plant site in Nottinghamshire has been selected as the future home of STEP (Spherical Tokamak for Energy Production), the U.K.’s planned prototype fusion energy plant. The government is providing £220 million (about $250 million) of funding for the first phase of STEP, which will see the UKAEA produce a concept design by 2024.
This fusion tokamak cutaway illustrates how the GAMBL concept would be incorporated into a fusion pilot plant. The SiC-tungsten composite wall provides superior heat-removal capabilities and durability, and a modular approach enables fabrication using existing technologies. (Image: GA)
Researchers at General Atomics (GA) are proposing a breeding blanket made of modular silicon carbide–based components to withstand the intense conditions in a high-power fusion power plant. The GA modular blanket (GAMBL) concept is described in an article published this month in the journal Fusion Engineering and Design, and was introduced by GA in a July 13 press release.
Government policies and innovative technologies are the key to fusion energy economics
Artist’s rendering of the U.K.'s STEP fusion reactor. (Image: U.K. Atomic Energy Authority)
Fusion energy is attracting significant interest from governments and private capital markets. The deployment of fusion energy on a timeline that will affect climate change and offer another tool for energy security will require support from stakeholders, regulators, and policymakers around the world. Without broad support, fusion may fail to reach its potential as a “game-changing” technology to make a meaningful difference in addressing the twin challenges of climate change and geopolitical energy security.
The process of developing the necessary policy and regulatory support is already underway around the world. Leaders in the United States, the United Kingdom, the European Union, China, and elsewhere are engaging with the key issues and will lead the way in setting the foundation for a global fusion industry.
[CLICK to see entire image] Overview of the SAS-VW program at DIII-D. A research concept map illustrates how intense plasma exhaust power entering the divertor leads to the emergence of impurities that can migrate into the plasma core. After identifying the research requirements for the SAS-VW, a process of engineering design, prototyping, and implementation is performed. (Image: General Atomics)
Researchers at the DIII-D National Fusion Facility (DIII-D) are preparing to test a new method that could enable future fusion power plants to withstand the heat and particle flow created by the fusion reaction, General Atomics reported this week.
Approval from French regulator ASN is required before ITER vacuum vessel welding can begin. (Photo: ITER)
In a February 28 article posted on the ITER Organization website, Gilles Perrier, head of ITER’s Safety and Quality Department, addressed the decision by French nuclear safety regulator ASN (Autorité de sûreté nucléaire) to delay the anticipated February 1 release of a preset tokamak assembly “hold point.”
The interior of JET with a superimposed plasma. (Image: EUROfusion)
A new record has been set by the world’s largest operating tokamak, the Joint European Torus (JET). According to the EUROfusion scientists and engineers who work on JET at the U.K. Atomic Energy Authority’s Culham Centre for Fusion Energy, the landmark experiment, announced on February 9, which produced 59 megajoules of fusion energy over five seconds, is powerful proof of fusion’s potential as a clean energy source.
Taken from above, this photo of the subassembly tool shows the complex system of alignment units used to slowly swing two toroidal field coils (bottom left and right) into position around the vacuum vessel sector. In the background, poloidal field coil #5 sits on the floor of the Assembly Hall, awaiting installation in the assembly pit in mid-September. (Photo: ITER)
Inside the ITER Assembly Hall, aided by a 20-meter-tall sector subassembly tool known as SSAT-2, the first of nine 40-degree wedge-shaped subassemblies that will make up the device’s tokamak is taking shape. On August 30, the ITER Organization announced that all the components of the first subassembly were in place on the SSAT-2. After the wings of the subassembly tool slowly close, locking two vertical coils in place around the outside of a vacuum vessel section that is already wrapped in thermal shielding, the completed subassembly will be ready for positioning in the ITER assembly pit in late October.
ITER CS Module 1 (shown here at right with the General Atomics fabrication team) is being loaded onto a specialized heavy transport vehicle for shipment to Houston, Texas, where it will be placed on a ship for transit to France. (Photo: General Atomics)
After a decade of design and fabrication, General Atomics (GA) is preparing to ship the first module of the central solenoid—the largest of ITER’s magnets—to the site in southern France where 35 partner countries are collaborating to build the world’s largest tokamak and the first fusion device to produce net energy.
Plasma in MAST. (Photo: UKAEA/EUROfusion)
As governments around the world cooperate on the ITER tokamak and, in parallel, race each other and private companies to develop commercial fusion power concepts, it seems that “game-changing” developments are proclaimed almost weekly. Recently, the United Kingdom and China announced new fusion program results.
The outside of the DIII-D tokamak, where testing that supports the development of the Compact Advanced Tokamak has been performed. Photo: General Atomics
Scientists at the DIII-D National Fusion Facility have published research on a compact fusion reactor design they say could be used to develop a pilot-scale fusion power plant. According to General Atomics (GA), which operates DIII-D as a national user facility for the Department of Energy’s Office of Science, the Compact Advanced Tokamak (CAT) concept uses a self-sustaining configuration that can hold energy more efficiently than in typical pulsed configurations, allowing the plant to be built at a reduced scale and cost.