A closer look at SPARC’s burning plasma ambitionsNuclear NewsResearch & ApplicationsOctober 5, 2020, 3:00PM|Nuclear News StaffCutaway of the SPARC engineering design. Image: CFS/MIT-PSFC, CAD rendering by T. HendersonSeven open-access, peer-reviewed papers on the design of SPARC, Commonwealth Fusion Systems’ (CFS) fusion tokamak, written in collaboration with the Massachusetts Institute of Technology’s Plasma Science and Fusion Center, were published on September 29 in a special edition of the Journal of Plasma Physics.The papers describe a compact fusion device that will achieve net energy where the plasma generates more fusion power than used to start and sustain the process, which is the requirement for a fusion power plant, according to CFS.The timeline for this planned device sets it apart from other magnetic confinement fusion tokamaks: Construction is to begin in 2021, with the device coming on line in 2025.CFS expects the device to achieve a burning plasma—a self-sustaining fusion reaction—and become the world’s first net energy (Q>1) fusion system. The newly released papers reflect more than two years of work by CFS and the Plasma Science and Fusion Center to refine their design. According to CFS, the papers apply the same physics rules and simulations used to design ITER, now under construction in France, and predict, based on results from existing experiments, that SPARC will achieve its goal of Q>2. In fact, the papers describe how, under certain parameters, SPARC could achieve a Q ratio of 10 or more.“These are concrete public predictions that when we build SPARC, the machine will produce net energy and even high gain fusion from the plasma,” said CFS’s chief executive officer, Bob Mumgaard. “That is a necessary condition to build a fusion power plant for which the world has been waiting decades. The combination of established plasma physics, new innovative magnets, and reduced scale opens new possibilities for commercial fusion energy in time to make a difference for climate change. This is a major milestone for the company and for the global clean tech effort as we work to get commercial fusion energy on the grid as fast as possible.”The plan, in brief: CFS was spun out of MIT in spring 2018 to take decades of fusion research into the private sector. The company continues to collaborate with MIT’s Plasma Science and Fusion Center.CFS envisions SPARC coming on line in 2025 as the world’s first net energy–producing fusion machine, fusing hydrogen isotopes deuterium and tritium and paving the way for the first commercial fusion power plant. To achieve fusion, the deuterium-tritium fuel must be heated to about 100 million degrees centigrade. Magnetic fields confine the charged plasma, insulating it from ordinary matter, and the stronger the magnetic field the stronger the confining force on the plasma.SPARC is being designed as a pulsed experiment and would not generate electricity, although CFS plans to follow SPARC with a net electricity–producing fusion pilot plant called ARC, which stands for affordable, robust, and compact.First, however, the team needs to build the magnets that would contain the plasma, an effort that is already under way. The team plans to demonstrate a 20-tesla, large-bore magnet next year, the same year that construction on SPARC would begin.About those magnets: While both ITER and SPARC would be magnetic confinement fusion tokamaks, SPARC would use high-temperature superconducting magnets made of rare earth barium copper oxide. According to CFS, the new high-temperature superconducting magnets can “enable a similar performance as ITER, but built more than 10 times smaller and on a significantly faster timeline.”The operational limits for plasma pressure, density, and current increase with magnetic field, yielding better performance. The SPARC design would be about twice the size of MIT’s now-retired Alcator C-Mod experiment but would achieve fusion performance comparable to that expected in the much larger ITER reactor.Martin Greenwald, deputy director of MIT’s Plasma Science and Fusion Center and one of the project’s lead scientists, wrote an editorial, titled “Status of the SPARC physics basics,” that was published in the journal. “The design for the ITER experiment explicitly required the highest possible magnetic field achievable with the niobium-based technology available at the time,” Greenwald said. “The use of a newer, higher field magnet technology enables similar levels of plasma performance in devices of considerably smaller size and thus lower capital cost.”The papers: The seven papers, for which 47 researchers from 12 institutions participated, summarize progress and outline the key research questions that SPARC is expected to help answer. The papers also identify the research needed to complete the final elements of the machine design and the operating procedures and tests that will be involved as work progresses toward a fusion power plant.In his editorial, Greenwald wrote, “Leveraging the broad progress in tokamak physics, the SPARC design has been fundamentally informed and optimized not only by empirical scaling (all data, no physics), but also by ‘first principles’ modeling (all physics, no data). Both approaches result in essentially the same prediction of overall plasma performance and fusion gain, thereby increasing confidence in the projections. Ongoing work features the use of state-of-the-art codes for calculation of ICRH [ion cyclotron resonance] heating, turbulent transport, pedestal structure, edge profiles, magnetohydrodynamics stability, and ripple losses of fast alphas.”Tags:commonwealth fusion systemsfusionmitsparcsuper-conducting magnetsShare:LinkedInTwitterFacebook
Understanding the ITER Project in the context of global Progress on Fusion(photo: ITER Project gangway assembly)The promise of hydrogen fusion as a safe, environmentally friendly, and virtually unlimited source of energy has motivated scientists and engineers for decades. For the general public, the pace of fusion research and development may at times appear to be slow. But for those on the inside, who understand both the technological challenges involved and the transformative impact that fusion can bring to human society in terms of the security of the long-term world energy supply, the extended investment is well worth it.Failure is not an option.Go to Article
General Fusion boasts backing from Shopify, Amazon foundersShopify founder Tobias Lütke is backing General Fusion with an undisclosed capital investment through his Thistledown Capital investment firm, the Canadian fusion technology firm announced January 14.In an article published the same day by TechCrunch, Jonathan Shieber noted that a separate investments by Jeff Bezos, founder and chief executive of Amazon, first made through his venture capital fund nearly a decade ago, means General Fusion “has the founders of the two biggest e-commerce companies in the Western world on its cap table.”Go to Article
Fusion and the bounty of electricityFrom the time we discovered how the sun produces energy, we have been captivated by the prospect of powering our society using the same principles of nuclear fusion. Fusion energy promises the bounty of electricity we need to live our lives without the pollution inherent in fossil fuels, such as oil, gas, and coal. In addition, fusion energy is free from the stigma that has long plagued nuclear power about the storage and handling of long-lived radioactive waste products, a stigma from which fission power is only just starting to recover in green energy circles. Go to Article
The year in review 2020: Research and ApplicationsHere is a look back at the top stories of 2020 from our Research and Applications section in Newswire and Nuclear News magazine. Remember to check back to Newswire soon for more top stories from 2020.Research and Applications sectionARDP picks divergent technologies in Natrium, Xe-100: Is nuclear’s future taking shape? The Department of Energy has put two reactor designs—TerraPower’s Natrium and X-energy’s Xe-100—on a fast track to commercialization, each with an initial $80 million in 50-50 cost-shared funds awarded through the Advanced Reactor Demonstration Program. Read more.Go to Article
Game-playing AI technique may lead to cheaper nuclear energyIn this AI-designed layout for a boiling water reactor, fuel rods are ideally positioned around two fixed water rods to burn more efficiently. MIT researchers ran the equivalent of 36,000 simulations to find the optimal configurations. Colors correspond to varying amounts of uranium and gadolinium oxide in each rod. Image: Majdi Radaideh/MITResearchers at the Massachusetts Institute of Technology and Exelon show that by turning the nuclear fuel assembly design process into a game, an artificial intelligence system can be trained to generate dozens of optimal configurations that can make each fuel rod last about 5 percent longer, saving a typical power plant an estimated $3 million a year, the researchers report.The AI system can also find optimal solutions faster than a human and can quickly modify designs in a safe, simulated environment. The results appear in the journal Nuclear Engineering and Design.Go to Article
ARC-20 cost-share funds go to ARC Nuclear, General Atomics, and MITDesigns chosen for ARC-20 support could be commercialized in the mid-2030s. Graphic: DOEThe Department of Energy’s Office of Nuclear Energy (DOE-NE) has named the recipients of $20 million in Fiscal Year 2020 awards for Advanced Reactor Concepts–20 (ARC-20), the third of three programs under its Advanced Reactor Demonstration Program (ARDP). The three selected teams—from Advanced Reactor Concepts LLC, General Atomics, and the Massachusetts Institute of Technology—will share the allocated FY20 funding for ARC-20 and bring the total number of projects funded through ARDP to 10. DOE-NE announced the news on December 22.The DOE expects to invest a total of about $56 million in ARC-20 over four years, with industry partners providing at least 20 percent in matching funds. The ARDP funding opportunity announcement, issued in May 2020, included ARC-20 awards, Advanced Reactor Demonstration awards, and Risk Reduction for Future Demonstration awards.Go to Article
Powering the future: Fusion advisory committee sets prioritiesThe Fusion Energy Science Advisory Committee (FESAC), which is responsible for advising the Department of Energy’s Office of Science, on December 4 published the first public draft of Powering the Future: Fusion and Plasmas, a 10-year vision for fusion energy and plasma science. FESAC was charged with developing a long-range plan in November 2018.The scope: The report, which is meant to catch the eye of leaders in the DOE, Congress, and the White House, details the needs of the fusion and plasma program identified by a FESAC subcommittee—the DOE Fusion Energy Sciences Advisory Committee for Long Range Planning—with the help of the fusion research community. The yearlong Phase 1 of the Community Planning Process, organized under the auspices of the American Physical Society’s Division of Plasma Physics, gathered input and yielded a strategic plan that is reflected in the FESAC’s draft report.Go to Article
U.K. seeks site for STEP fusion reactorThe United Kingdom’s Department for Business, Energy and Industrial Strategy has asked local governments to submit bids to host the Spherical Tokamak for Energy Production project, or STEP, according to an article published by Bloomberg on December 1. The STEP plant will be developed by the U.K. Atomic Energy Authority, which says that construction could begin as soon as 2032, with operations by 2040, and “will prove that fusion is not a far-off dream.”Go to Article
2020 ANS Virtual Winter Meeting: Fusion technology start-ups showcased at TOFE 2020The Fusion Enterprise-I and -II sessions, held on November 18 as part of the TOFE 2020 embedded topical meeting at the 2020 ANS Virtual Winter Meeting, were chaired by Ales Necas, principal scientist at TAE Technologies, and featured presentations by speakers representing companies in the commercial fusion area.Go to Article
Is proximity key to understanding interactions on the nuclear scale?An MIT-led team found that the formulas describing how atoms behave in a gas can be generalized to predict how protons and neutrons interact at close range. Image: Collage by MIT News. Neutron star image: X-ray (NASA/CXC/ESO/F.Vogt et al); Optical (ESO/VLT/MUSE & NASA/STScI)In an MIT News article playfully titled “No matter the size of a nuclear party, some protons and neutrons will always pair up and dance,” author Jennifer Chu explains that findings on the interactions of protons and neutrons recently published in the journal Nature Physics show that the nucleons may behave like atoms in a gas.A Massachusetts Institute of Technology–led team simulated the behavior of nucleons in several types of atomic nuclei using supercomputers at Los Alamos National Laboratory and Argonne National Laboratory. The team investigated a range of nuclear interaction models and found that formulas describing a concept known as contact formalism can be generalized to predict how protons and neutrons interact at close range.Go to Article