Dan Drollette Jr
Nuclear fusion as a source of electricity always seems to be just around the corner. As the old joke goes, “Thirty years ago, fusion was 30 years away from becoming a viable commercial reality”—a comment borne out in the Bulletin’s own pages, if not precisely on a 30-year timescale.
In 1971, physicist Richard Post of what was then the Lawrence Radiation Laboratory published a Bulletin of the Atomic Scientists’ article featuring a chart that showed how fusion—that is, the fusing of hydrogen atoms to release energy, a process that powers all stars, including the Earth’s sun—would be widely available on a commercial scale, routinely pumping electrons to the electrical grid, by the year 1990 (although he hedged his bets by labeling it “An Optimist’s Fusion Power Timetable” [emphasis added]).
That optimism was widely shared, judging from the literature in the science and technology press of the time. But it proved to be misplaced; although militaries have thousands of nuclear warheads based on the fusion process, everything about commercial fusion as an energy has proven harder and taken longer than expected. For example, more than 60 years passed since the development of the first fusion “tokamak” reactor in the old Soviet Union to the first sustained fusion “burn,” or ignition, at the National Ignition Facility in the United States in 2022.
The difficulties involved in creating a commercial power plant are relatively simple to enumerate, as plasma physicist Bob Rosner—himself the former director of a national laboratory (and former chair of the Bulletin’s Science and Security Board)—explains in his interview, “Ferreting out the truth about fusion.” In a nutshell, the fusion process releases neutrons that are 10 times more energetic than what a commercial plant powered by the splitting of atoms, or nuclear fission, ordinarily emits. These high-powered neutrons are difficult to contain and rapidly degrade the containers proposed for controlling the extremely hot plasma required for a fusion reaction. At the same time, plasmas are just plain difficult to keep stable while producing that all-important steady (or quasi-steady) fusion “burn.” In fact, Rosner notes, it’s likely that if a disruptive instability ever happens at ITER—the giant international research and engineering effort, based in France, that seeks to demonstrate how fusion could be produced in a magnetic fusion device—the multibillion-dollar experimental facility likely would not recover. For these reasons and more, Rosner asserts that commercial-scale, tokamak-style fusion will not be a reality in his lifetime—“and I think not in my children’s lifetime, or my grandchildren’s lifetime.” In addition, he warns about the hype and public relations fluff surrounding overly rosy projections for fusion, or what Rosner terms “a complex mixture of fact, half-truths and outright misinformation.”
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