Fusion energy research has seen exciting recent breakthroughs. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has achieved ignition,^1,2 and in the United Kingdom, the Culham Centre for Fusion Energy’s Joint European Torus (JET) has produced a record 59 megajoules of fusion energy.³ Against this backdrop of advances, we provide an account of the earliest fusion discoveries from the 1930s to the 1950s.* Some of this technical history has not been previously appreciated—most notably the first 1938 reporting of deuterium-tritium (DT) 14-MeV neutrons at the University of Michigan by Arthur Ruhlig.⁴ This experiment had a critical role in inspiring early thermonuclear fusion research directions. This article presents some unique insights from the extensive holdings within Los Alamos National Laboratory’s archives—including sources typically unavailable to a broad audience.

The question of what to do with the radioactive waste has been raised frequently for both fission and fusion. In the 1970s, fusion adopted the land-based disposal option, primarily based on the Nuclear Regulatory Commission’s decision to regulate all radioactive wastes as only a disposal issue, following the fission guidelines. In the early 2000s, members of the Advanced Research Innovation and Evaluation Study (ARIES) national team became increasingly aware of the high amount of mildly radioactive materials that 1-GWe fusion power plants will generate, compared with the current line of fission reactors. The main concern is that such a sizable inventory of mostly tritiated radioactive materials would tend to rapidly fill U.S. repositories—a serious issue that was overlooked in early fusion studies¹ that could influence the public acceptability of fusion energy and will certainly become more significant in the immediate future if left unaddressed, as fusion moves toward commercialization.

Nuclear fusion “might actually be on the cusp of commercial viability” today, says a recent article in Fortune magazine. The article offers a brief review of recent technical and entrepreneurial developments in fusion energy. It also places these developments in perspective regarding the hurdles that remain before commercialization can be realized.

Barabaschi

Capping a session in Paris, the ITER Council has unanimously selected Pietro Barabaschi as the new director-general of the ITER Organization. The Italian-born Barabaschi, who has been involved in nuclear fusion research for some 30 years, was chosen to lead the massive international fusion project following an intensive recruitment effort necessitated by the death of Bernard Bigot, the previous director general, in May. Since Bigot’s death, Eisuke Tada has been serving in the role in an interim capacity. Barabaschi will take office in October.

F4E leader: Barabaschi has been the head of the Broader Approach Programme and Delivery with Fusion for Energy (F4E) since 2008. F4E is the EU organization responsible for Europe’s contribution to ITER. In this position, he has been managing the department that oversees three projects stemming from the Broader Approach agreement between the European Atomic Energy Community (Euratom) and the government of Japan: the JT-60SA tokamak, the International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities linear accelerator, and the International Fusion Energy Research Centre . Barabaschi has also been acting director of F4E.

As citizens of the United Kingdom and others around the world mourn the death of Queen Elizabeth II, many have reflected on how the world has changed during the seven decades of the queen’s reign—the same decades that saw the rise of civilian nuclear power.

Calder Hall was already under construction at the Sellafield site in West Cumbria when Princess Elizabeth became queen in 1953. Queen Elizabeth traveled to the site in October 1956 and declared, in a televised ceremony, that “It is with pride that I now open Calder Hall, Britain’s first atomic power station.” Watch the fanfare in a historical clip uploaded to YouTube by Sellafield Ltd below.

Fusion energy is no longer a far-off goal. It is now routinely achieved at laboratory scale but requires more energy to control the fusion reaction than the fusion reaction has released.

The path to viable fusion power from a magnetically confined plasma source requires the creation of a burning plasma, whereby the primary heating source comes from the fusion reaction itself.

To begin to consider the economic viability of a fusion power plant, the reaction must have a significant energy gain, or “Q” factor (the ratio of output power to input heating power), in a reaction that is sustained over a time frame of minutes or hours.

Construction has begun on an international experiment—the ITER tokamak—that aims to achieve a sustained reaction, and numerous privately funded smaller experiments have the potential to move forward toward this goal.

Nuclear News reached out to companies in the fusion community to ask for insights into their ongoing work. All are members of the Fusion Industry Association. Most companies submitted briefs at a specified word count, while others ran long and some ran short. Their insights appear on the following pages.

The ST25-HTS tokamak.

Governments around the world have been interested in fusion for more than 70 years. Fusion research was largely secret until 1968, when the Soviets unveiled exciting results from their tokamak (a magnetic confinement fusion device with a particular configuration that produces a toroidal plasma). The Soviets realized that tokamaks were not useful as weapons but could produce plasma in the million-degree temperature range to demonstrate Soviet scientific and technical prowess to the world.

Following this breakthrough, government laboratories around the world continued to pursue various methods of confining hot plasma to understand plasma physics under extreme conditions, getting closer and closer to the conditions necessary for fusion energy production. Tokamaks have been by far the most successful configuration. In the 1990s, the Tokamak Fusion Test Reactor at the Princeton Plasma Physics Laboratory produced 10 MW of fusion power using deuterium-tritium fusion. A few years later, the Joint European Torus (JET) in the United Kingdom increased that to 16 MW, getting close to breakeven using 24 MW of power to heat the plasma.

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.