New model stretches the limits of fusion torus control

The 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.

Illustration of a Mars transit habitat and nuclear electric propulsion system. Image: NASA

NASA aims to develop nuclear technologies for two space applications: propulsion and surface power. Both can make planned NASA missions to the moon more agile and more ambitious, and both are being developed with future crewed missions to Mars in mind. Like advanced reactors here on Earth, space nuclear technologies have an accelerated timeline for deployment in this decade.

Space nuclear propulsion and extraterrestrial surface power are getting funding and attention. New industry solicitations are expected this month, and a range of proposed reactor technologies could meet NASA’s specifications for nuclear thermal propulsion (NTP). Nuclear electric propulsion could increase the feasibility of crewed missions to Mars with a shorter transit time, a broader launch window and more flexibility to abort missions, reduced astronaut exposure to space radiation and other hazards, expanded payload mass capabilities, and reduced cost.

You may have read the abbreviated version of this article in the November 2020 issue of Nuclear News. Now here's the full article—enjoy!

I have enjoyed a long and stimulating career in applied nuclear physics—specifically nuclear reactor physics, nuclear fusion plasma physics, and nuclear fission and fusion reactor design—which has enabled me to know and interact with many of the scientists and engineers who have brought the field of nuclear energy forward over the past half-century. In this time I have had the fortune to interact with and contribute (directly and indirectly) to the education of many of the people who will carry the field forward over the next half-century.

Advanced reactor developers see potential markets for reactors in a range of sizes that offer clean, reliable, flexible, and cost-competitive power. Many have reached agreements with suppliers, utilities, and others to support the demonstration and possible deployment of their designs. Nuclear News is following these activities. Read on for updates and check back with Newswire often for more on the Advanced Reactor Marketplace.

Canada has invested Can$20 million in Terrestrial Energy’s 195-MW Integral Molten Salt Reactor through the Ministry of Innovation, Science and Industry, the company announced on October 15. In accepting the investment, Terrestrial Energy, which is based in Oakville, Ontario, has committed to creating and maintaining 186 jobs and creating 52 co-op positions nationally. In addition, Terrestrial Energy is spending at least $91.5 million on research and development. According to the company, the funds will assist with the completion of a key pre-licensing milestone with the Canadian Nuclear Safety Commission.

Two days earlier, Terrestrial Energy USA and Centrus Energy announced that they had signed a memorandum of understanding to evaluate the logistical, regulatory, and transportation requirements to establish a fuel supply for Integral Molten Salt Reactor power plants, which would use standard-assay low-enriched uranium at an enrichment level less than 5 percent.

Cutaway of the SPARC engineering design. Image: CFS/MIT-PSFC, CAD rendering by T. Henderson

Seven 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.

Cutaway of the SPARC engineering design. Image: CFS/MIT-PSFC, CAD Rendering by T. Henderson

A special issue of the Journal of Plasma Physics gives a glimpse into the physics basis for SPARC, the DT-burning tokamak being designed by a team from the Massachusetts Institute of Technology and Commonwealth Fusion Systems. The special issue was announced in a September 29 post on the Cambridge University Press blog Cambridge Core.

The special JPP issue includes seven peer-reviewed articles on the SPARC concept, which takes advantage of recent breakthroughs in high-temperature superconductor technology to burn plasma in a compact tokamak design.

The NSTX-U “umbrella.” Photo: Elle Starkman/ PPPL Office of Communications

The Department of Energy on September 8 announced funding for research at the National Spherical Tokamak Experiment Upgrade (NSTX-U), an Office of Science user facility at the DOE’s Princeton Plasma Physics Laboratory in Princeton, N.J.

Total planned funding is $17 million for the NSTX-U work over five years in duration. As much as $6 million in fiscal year 2020 dollars and out-year funding could be available this year, contingent on congressional appropriations and satisfactory progress.

The initiative will support experiments, data analysis, and computer modeling and simulation of plasma behavior. A major focus will be on the start of laying the scientific groundwork for a next-generation facility through better understanding of the behavior of plasmas in spherical tokamaks, the DOE said.

A look inside the TFTR plasma vessel. Photo: DOE

The Tokamak Fusion Test Reactor (TFTR) at Princeton University and the Fuel Cycle Facility (FCF) (now known as the Fuel Conditioning Facility) at Idaho National Laboratory have been designated as ANS Nuclear Historic Landmarks. The official awarding of the honors will occur during the 2020 ANS Virtual Winter Meeting, which begins November 16.

The TFTR received the award for demonstrating significant fusion energy production and tritium technologies for future nuclear fusion power plants and for the first detailed exploration of magnetically confined deuterium-tritium (D-T) fusion plasmas.

INL’s FCF and its Experimental Breeder Reactor II (EBR-II) were honored for demonstrating on-site recycling of used nuclear fuel back into a nuclear reactor.

The Department of Energy announced on September 2 that it has issued $29 million in funding for 14 projects as part of its Galvanizing Advances in Market-aligned fusion for an Overabundance of Watts (GAMOW) program, which is jointly sponsored by the department’s Advanced Research Projects Agency–Energy (ARPA-E) and the Office of Science–Fusion Energy Sciences (SC-FES).

According to the DOE, GAMOW teams will work to close multiple fusion-specific technological gaps that will be needed to connect a net-energy-gain “fusion core,” once it is ready, to a deployable, commercially attractive fusion system.

The Department of Energy on August 19 announced several awards to research teams applying artificial intelligence and machine learning to fusion energy. The planned total funding of $21 million is targeted at projects with time frames of up to three years; $8 million in fiscal year 2020 funding has already been committed to the work. Delivery of the balance-of-project funding will depend on future congressional appropriations.

“These awards will enable fusion researchers to take advantage of recent rapid advances in artificial intelligence and machine learning,” said Chris Fall, director of the DOE’s Office of Science. “AI and ML will help us to accelerate progress in fusion and keep American scientists at the forefront of fusion research.”