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      New study shows how universities are critical to emerging fusion industry

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      A new study suggests that universities have an essential role to fulfill in the continued growth and success of any modern high-tech industry, and especially the nascent fusion industry; however, the importance of that role is not reflected in the number of fusion-oriented faculty and educational channels currently available. Academia’s responsiveness to the birth of other modern scientific fields, such as aeronautics and nuclear fission, provides a template for the steps universities can take to enable a robust fusion industry.

      Authored by Dennis Whyte, the Hitachi America Professor of Engineering and director of the Plasma Science and Fusion Center at MIT; Carlos Paz-Soldan, associate professor of applied physics and applied mathematics at Columbia University; and Brian D. Wirth, the Governor’s Chair Professor of Computational Nuclear Engineering at the University of Tennessee, the paper was recently published in the journal Physics of Plasmas as part of a special collection titled “Private Fusion Research: Opportunities and Challenges in Plasma Science.”

      With contributions from authors in academia, government, and private industry, the collection outlines a framework for public-private partnerships that will be essential for the success of the fusion industry.

      Now being seen as a potential source of unlimited green energy, fusion is the same process that powers the sun — hydrogen atoms combine to form helium, releasing vast amounts of clean energy in the form of light and heat.

      The excitement surrounding fusion’s arrival has resulted in the proliferation of dozens of for-profit companies positioning themselves at the forefront of the commercial fusion energy industry. In the near future, those companies will require a significant network of fusion-fluent workers to take on varied tasks requiring a range of skills.

      While the authors acknowledge the role of private industry, especially as an increasingly dominant source of research funding, they also show that academia is and will continue to be critical to industry’s development, and it cannot be decoupled from private industry’s growth. Despite the evidence of this burgeoning interest, the size and scale of the field’s academic network at U.S.-based universities is sparse.

      According to Whyte, “Diversifying the [fusion] field by adding more tracks for master’s students and undergraduates who can transition into industry more quickly is an important step.”

      An analysis found that while there are 57 universities in the United States active in plasma and fusion research, the average number of tenured or tenure-track plasma/fusion faculty at each institution is only two. By comparison, a sampling of US News and World Report’s top 10 programs for nuclear fission and aeronautics/astronautics found an average of nearly 20 faculty devoted to fission and 32 to aero/astro.

      “University programs in fusion and their sponsors need to up their game and hire additional faculty if they want to provide the necessary workforce to support a growing U.S. fusion industry,” adds Paz-Soldan.

      The growth and proliferation of those fields and others, such as computing and biotechnology, were historically in lockstep with the creation of academic programs that helped drive the fields’ progress and widespread acceptance. Creating a similar path for fusion is essential to ensuring its sustainable growth, and as Wirth notes, “that this growth should be pursued in a way that is interdisciplinary across numerous engineering and science disciplines.”

      At MIT, an example of that path is seen at the Plasma Science and Fusion Center.

      The center has deep historical ties to government research programs, and the largest fusion company in the world, Commonwealth Fusion Systems (CFS), was spun out of the PSFC by Whyte’s former students and an MIT postdoc. Whyte also serves as the primary investigator in collaborative research with CFS on SPARC, a proof-of-concept fusion platform for advancing tokamak science that is scheduled for completion in 2025.

      “Public and private roles in the fusion community are rapidly evolving in response to the growth of privately funded commercial product development,” says Michael Segal, head of open innovation at CFS. “The fusion industry will increasingly rely on its university partners to train students, work across diverse disciplines, and execute small and midsize programs at speed.”

      According to the authors, another key reason academia will remain essential to the continued growth and development of fusion is because it is unconflicted. Whyte comments, “Our mandate is sharing information and education, which means we have no competitive conflict and innovation can flow freely.” Furthermore, fusion science is inherently multidisciplinary: “[It] requires physicists, computer scientists, engineers, chemists, etc. and it’s easy to tap into all those disciplines in an academic environment where they’re all naturally rubbing elbows and collaborating.”

      Creating a new energy industry, however, will also require a workforce skilled in disciplines other than STEM, say the authors. As fusion companies continue to grow, they will need expertise in finance, safety, licensing, and market analysis. Any successful fusion enterprise will also have major geopolitical, societal, and economic impacts, all of which must be managed.

      Ultimately, there are several steps the authors identify to help build the connections between academia and industry that will be important going forward: The first is for universities to acknowledge the rapidly changing fusion landscape and begin to adapt. “Universities need to embrace the growth of the private sector in fusion, recognize the opportunities it provides, and seek out mutually beneficial partnerships,” says Paz-Soldan.

      The second step is to reconcile the mission of educational institutions — unconflicted open access — with condensed timelines and proprietary outputs that come with private partnerships. At the same time, the authors note that private fusion companies should embrace the transparency of academia by publishing and sharing the findings they can through peer-reviewed journals, which will be a necessary part of building the industry’s credibility.

      The last step, the authors say, is for universities to become more flexible and creative in their technology licensing strategies to ensure ideas and innovations find their way from the lab into industry.

      “As an industry, we’re in a unique position because everything is brand new,” Whyte says. “But we’re enough students of history that we can see what’s needed to succeed; quantifying the status of the private and academic landscape is an important strategic touchstone. By drawing attention to the current trajectory, hopefully we’ll be in a better position to work with our colleagues in the public and private sector and make better-informed choices about how to proceed.” More

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      How to decarbonize the world, at scale

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      The world in recent years has largely been moving on from debates about the need to curb carbon emissions and focusing more on action — the development, implementation, and deployment of the technological, economic, and policy measures to spur the scale of reductions needed by mid-century. That was the message Robert Stoner, the interim director of the MIT Energy Initiative (MITEI), gave in his opening remarks at the 2023 MITEI Annual Research Conference.

      Attendees at the two-day conference included faculty members, researchers, industry and financial leaders, government officials, and students, as well as more than 50 online participants from around the world.

      “We are at an extraordinary inflection point. We have this narrow window in time to mitigate the worst effects of climate change by transforming our entire energy system and economy,” said Jonah Wagner, the chief strategist of the U.S. Department of Energy’s (DOE) Loan Programs Office, in one of the conference’s keynote speeches.

      Yet the solutions exist, he said. “Most of the technologies that we need to deploy to stay close to the international target of 1.5 degrees Celsius warming are proven and ready to go,” he said. “We have over 80 percent of the technologies we will need through 2030, and at least half of the technologies we will need through 2050.”

      For example, Wagner pointed to the newly commissioned advanced nuclear power plant near Augusta, Georgia — the first new nuclear reactor built in the United States in a generation, partly funded through DOE loans. “It will be the largest source of clean power in America,” he said. Though implementing all the needed technologies in the United States through mid-century will cost an estimated $10 trillion, or about $300 billion a year, most of that money will come from the private sector, he said.

      As the United States faces what he describes as “a tsunami of distributed energy production,” one key example of the strategy that’s needed going forward, he said, is encouraging the development of virtual power plants (VPPs). The U.S. power grid is growing, he said, and will add 200 gigawatts of peak demand by 2030. But rather than building new, large power plants to satisfy that need, much of the increase can be accommodated by VPPs, he said — which are “aggregations of distributed energy resources like rooftop solar with batteries, like electric vehicles (EVs) and chargers, like smart appliances, commercial and industrial loads on the grid that can be used together to help balance supply and demand just like a traditional power plant.” For example, by shifting the time of demand for some applications where the timing is not critical, such as recharging EVs late at night instead of right after getting home from work when demand may be peaking, the need for extra peak power can be alleviated.

      Such programs “offer a broad range of benefits,” including affordability, reliability and resilience, decarbonization, and emissions reductions. But implementing such systems on a wide scale requires some up-front help, he explained. Payment for consumers to enroll in programs that allow such time adjustments “is the majority of the cost” of establishing VPPs, he says, “and that means most of the money spent on VPPs goes back into the pockets of American consumers.” But to make that happen, there is a need for standardization of VPP operations “so that we are not recreating the wheel every single time we deploy a pilot or an effort with a utility.”

      The conference’s other keynote speaker, Anne White, the vice provost and associate vice president for research administration at MIT, cited devastating recent floods, wildfires, and many other extreme weather-related crises around the world that have been exacerbated by climate change. “We saw in myriad ways that energy concerns and climate concerns are one and the same,” she said. “So, we must urgently develop and scale low-carbon and zero-carbon solutions to prevent future warming. And we must do this with a practical, systems-based approach that considers efficiency, affordability, equity, and sustainability for how the world will meet its energy needs.”

      White added that at MIT, “we are mobilizing everything.” People at MIT feel a strong sense of responsibility for dealing with these global issues, she said, “and I think it’s because we believe we have tools that can really make a difference.”

      Among the specific promising technologies that have sprung from MIT’s labs, she pointed out, is the rapid development of fusion technology that led to MIT spinoff company Commonwealth Fusion Systems, which aims to build a demonstration unit of a practical fusion power reactor by the decade’s end. That’s an outcome of decades of research, she emphasized — the kinds of early-stage risky work that only academic labs, with help from government grants, can carry out.

      For example, she pointed to the more than 200 projects that MITEI has provided seed funds of $150,000 each for two years, totaling over $28 million to date. Such early support is “a key part of producing the kind of transformative innovation we know we all need.” In addition, MIT’s The Engine has also helped launch not only Commonwealth Fusion Systems, but also Form Energy, a company building a plant in West Virginia to manufacture advanced iron-air batteries for renewable energy storage, and many others.

      Following that theme of supporting early innovation, the conference featured two panels that served to highlight the work of students and alumni and their energy-related startup companies. First, a startup showcase, moderated by Catarina Madeira, the director of MIT’s Startup Exchange, featured presentations about seven recent spinoff companies that are developing cutting-edge technologies that emerged from MIT research. These included:

      Aeroshield, developing a new kind of highly-insulated window using a unique aerogel material;
      Sublime, which is developing a low-emissions concrete;
      Found Energy, developing a way to use recycled aluminum as a fuel;
      Veir, developing superconducting power lines;
      Emvolom, developing inexpensive green fuels from waste gases;
      Boston Metal, developing low-emissions production processes for steel and other metals;
      Transaera, with a new kind of efficient air conditioning; and
      Carbon Recycling International, producing cheap hydrogen fuel and syngas.
      Later in the conference, a “student slam competition” featured presentations by 11 students who described results of energy projects they had been working on this past summer. The projects were as diverse as analyzing opposition to wind farms in Maine, how best to allocate EV charging stations, optimizing bioenergy production, recycling the lithium from batteries, encouraging adoption of heat pumps, and conflict analysis about energy project siting. Attendees voted on the quality of the student presentations, and electrical engineering and computer science student Tori Hagenlocker was declared first-place winner for her talk on heat pump adoption.

      Students were also featured in a first-time addition to the conference: a panel discussion among five current or recent students, giving their perspective on today’s energy issues and priorities, and how they are working toward trying to make a difference. Andres Alvarez, a recent graduate in nuclear engineering, described his work with a startup focused on identifying and supporting early-stage ideas that have potential. Graduate student Dyanna Jaye of urban studies and planning spoke about her work helping to launch a group called the Sunrise Movement to try to drive climate change as a top priority for the country, and her work helping to develop the Green New Deal.

      Peter Scott, a graduate student in mechanical engineering who is studying green hydrogen production, spoke of the need for a “very drastic and rapid phaseout of current, existing fossil fuels” and a halt on developing new sources. Amar Dayal, an MBA candidate at the MIT Sloan School of Management, talked about the interplay between technology and policy, and the crucial role that legislation like the Inflation Reduction Act can have in enabling new energy technology to make the climb to commercialization. And Shreyaa Raghavan, a doctoral student in the Institute of Data, Systems, and Society, talked about the importance of multidisciplinary approaches to climate issues, including the important role of computer science. She added that MIT does well on this compared to other institutions, and “sustainability and decarbonization is a pillar in a lot of the different departments and programs that exist here.”

      Some recent recipients of MITEI’s Seed Fund grants reported on their progress in a panel discussion moderated by MITEI Executive Director Martha Broad. Seed grant recipient Ariel Furst, a professor of chemical engineering, pointed out that access to electricity is very much concentrated in the global North and that, overall, one in 10 people worldwide lacks access to electricity and some 2.5 billion people “rely on dirty fuels to heat their homes and cook their food,” with impacts on both health and climate. The solution her project is developing involves using DNA molecules combined with catalysts to passively convert captured carbon dioxide into ethylene, a widely used chemical feedstock and fuel. Kerri Cahoy, a professor of aeronautics and astronautics, described her work on a system for monitoring methane emissions and power-line conditions by using satellite-based sensors. She and her team found that power lines often begin emitting detectable broadband radio frequencies long before they actually fail in a way that could spark fires.

      Admir Masic, an associate professor of civil and environmental engineering, described work on mining the ocean for minerals such as magnesium hydroxide to be used for carbon capture. The process can turn carbon dioxide into solid material that is stable over geological times and potentially usable as a construction material. Kripa Varanasi, a professor of mechanical engineering, said that over the years MITEI seed funding helped some of his projects that “went on to become startup companies, and some of them are thriving.” He described ongoing work on a new kind of electrolyzer for green hydrogen production. He developed a system using bubble-attracting surfaces to increase the efficiency of bioreactors that generate hydrogen fuel.

      A series of panel discussions over the two days covered a range of topics related to technologies and policies that could make a difference in combating climate change. On the technological side, one panel led by Randall Field, the executive director of MITEI’s Future Energy Systems Center, looked at large, hard-to-decarbonize industrial processes. Antoine Allanore, a professor of metallurgy, described progress in developing innovative processes for producing iron and steel, among the world’s most used commodities, in a way that drastically reduces greenhouse gas emissions. Greg Wilson of JERA Americas described the potential for ammonia produced from renewable sources to substitute for natural gas in power plants, greatly reducing emissions. Yet-Ming Chiang, a professor in materials science and engineering, described ways to decarbonize cement production using a novel low-temperature process. And Guiyan Zang, a research scientist at MITEI, spoke of efforts to reduce the carbon footprint of producing ethylene, a major industrial chemical, by using an electrochemical process.

      Another panel, led by Jacopo Buongiorno, professor of nuclear science and engineering, explored the brightening future for expansion of nuclear power, including new, small, modular reactors that are finally emerging into commercial demonstration. “There is for the first time truly here in the U.S. in at least a decade-and-a-half, a lot of excitement, a lot of attention towards nuclear,” Buongiorno said. Nuclear power currently produces 45 to 50 percent of the nation’s carbon-free electricity, the panelists said, and with the first new nuclear power plant in decades now in operation, the stage is set for significant growth.

      Carbon capture and sequestration was the subject of a panel led by David Babson, the executive director of MIT’s Climate Grand Challenges program. MIT professors Betar Gallant and Kripa Varanasi and industry representatives Elisabeth Birkeland from Equinor and Luc Huyse from Chevron Technology Ventures described significant progress in various approaches to recovering carbon dioxide from power plant emissions, from the air, and from the ocean, and converting it into fuels, construction materials, or other valuable commodities.

      Some panel discussions also addressed the financial and policy side of the climate issue. A panel on geopolitical implications of the energy transition was moderated by MITEI Deputy Director of Policy Christopher Knittel, who said “energy has always been synonymous with geopolitics.” He said that as concerns shift from where to find the oil and gas to where is the cobalt and nickel and other elements that will be needed, “not only are we worried about where the deposits of natural resources are, but we’re going to be more and more worried about how governments are incentivizing the transition” to developing this new mix of natural resources. Panelist Suzanne Berger, an Institute professor, said “we’re now at a moment of unique openness and opportunity for creating a new American production system,” one that is much more efficient and less carbon-producing.

      One panel dealt with the investor’s perspective on the possibilities and pitfalls of emerging energy technologies. Moderator Jacqueline Pless, an assistant professor in MIT Sloan, said “there’s a lot of momentum now in this space. It’s a really ripe time for investing,” but the risks are real. “Tons of investment is needed in some very big and uncertain technologies.”

      The role that large, established companies can play in leading a transition to cleaner energy was addressed by another panel. Moderator J.J. Laukatis, MITEI’s director of member services, said that “the scale of this transformation is massive, and it will also be very different from anything we’ve seen in the past. We’re going to have to scale up complex new technologies and systems across the board, from hydrogen to EVs to the electrical grid, at rates we haven’t done before.” And doing so will require a concerted effort that includes industry as well as government and academia. More

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      Rafael Mariano Grossi speaks about nuclear power’s role at a critical moment in history

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      On Sept. 22, Rafael Mariano Grossi, director general of the International Atomic Energy Agency (IAEA), delivered the 2023 David J. Rose Lecture in Nuclear Technology at MIT. This lecture series was started nearly 40 years ago in honor of the late Professor David Rose — a nuclear engineering professor and fusion technology pioneer. In addition to his scientific contributions, Rose was invested in the ethical issues associated with new technologies. His widow, Renate Rose, who spoke briefly before Grossi’s lecture, said that her husband adamantly called for the abolishment of nuclear weapons, insisting that all science should serve the common good and that every scientist should follow his or her conscience.

      In his prefatory remarks, MIT Vice Provost Richard Lester, a former PhD student of David Rose, said that even today, he still feels the influence of his thesis advisor, many decades after they’d worked together. Lester called it a “great honor” to introduce Grossi, noting that the director general was guiding the agency through an especially demanding time. “His presence with us is a reminder that the biggest challenges we face today are truly global challenges, and that international organizations like the IAEA have a central role to play in resolving them.”

      The title of Grossi’s talk was “The IAEA at the Crossroads of History,” and he made a strong case for this being a critical juncture, or “inflection point,” for nuclear power. He started his speech, however, with somewhat of an historical footnote, discussing a letter that Rose sent in 1977 to Sigvard Eklund, IAEA’s then-director general. Rose urged the IAEA to establish a coordinated worldwide program in controlled fusion research. It took a while for the idea to gain traction, but international collaboration in fusion formally began in 1985, eight years after Rose’s proposal. “I thought I would begin with this story, because it shows that cooperation between MIT and the IAEA goes back a long way,” Grossi said.

      2023 David J. Rose Lecture in Nuclear TechnologyVideo: MIT Department of Nuclear Science and Engineering

      Overall, he painted a mostly encouraging picture for the future of nuclear power, largely based on its potential to generate electricity or thermal energy without adding greenhouse gases to the atmosphere. In the face of rapidly-unfolding climate change, Grossi said, “low-carbon nuclear power is now seen as part of [the] solution by an increasing number of people. It’s getting harder to be an environmentalist in good faith who is against nuclear.”

      Public acceptance is growing throughout the world, he added. In Sweden, where people had long protested against radioactive waste transport, a poll now shows that more than 85 percent of the people approve of the nation’s high-level waste handling and disposal facilities. Even Finland’s Green Party has embraced nuclear power, Grossi said. “I don’t think we could imagine a pro-nuclear Green Party five years ago, let alone in 1970 or ’80.”

      Fifty-seven nuclear reactors are being constructed right now in 17 countries. One of the world’s newest facilities, the Barakah nuclear power plant in the United Arab Emirates, “was built on ground rich in oil and natural gas,” he said. In China, the world’s first pebble-bed high-temperature reactor has been operating for two years, offering potential advantages in safety, efficiency, and modularity. For countries that don’t have any nuclear plants, small modular reactors of this kind “offer the chance of a more gradual and affordable way to scale up nuclear power,” Grossi noted. The IAEA is working with countries like Ghana, Kenya, and Senegal to help them develop the safety and regulatory infrastructures that would be needed to build and responsibly operate modular nuclear reactors like this.

      Grossi also discussed a number of lesser-known projects the IAEA is engaged in that have little to do with power generation. Seventy percent of the people in Africa, for example, have no access to radiotherapy to fight cancer. To this end, the IAEA is now helping to provide radiotherapy services in Tanzania and other African countries. At the IAEA’s Marine Environmental Laboratories in Monaco, researchers are using isotopic tracing techniques to study the impact of microplastic pollution on the oceans. The Covid-19 pandemic illustrated the potentially devastating effects of zoonotic diseases that can infect humans with animal-borne viruses. To counteract this threat, the IAEA has sent hundreds of reverse transcription-polymerase chain reaction (RT-PCR) machines — capable of detecting specific genetic materials in pathogens — to more than 130 countries.

      Meanwhile, new risks have emerged from the war in Ukraine, where fighting has raged for a year-and-a-half near the six nuclear reactors in Zaporizhzhia — Europe’s largest nuclear power plant. Early in the conflict, the IAEA sent a team of experts to monitor the plant and to do everything possible to prevent a nuclear accident that would bring “even more misery to people who are already suffering so much,” Grossi said. A major accident, he added, would likely stall investments in nuclear power at a time when its future prospects were starting to brighten.

      At the end of his talk, Grossi returned to the subject of fusion, which he expects to become an important energy source, perhaps in the not-too-distant future. He was encouraged by the visit he’d just had to the MIT spinoff company, Commonwealth Fusion Systems. With regard to fusion, he said, “for the first time, all the pieces of the puzzle are there: the physics, the policy drivers, and the investment.” In fact, an agreement was signed on the day of his lecture, which made MIT’s Plasma Science and Fusion Center an IAEA collaboration center — the second such center in the United States.

      “When I think of all the new forms of collaboration happening today, I imagine Professor Rose would be delighted,” Grossi said. “It really is something to hold [his] letter and know how much progress has been made since 1977 in fusion. I look forward to our collaboration going forward.” More

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      3 Questions: What should scientists and the public know about nuclear waste?

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      Many researchers see an expansion of nuclear power, which produces no greenhouse gas emissions from its power generation, as an essential component of strategies to combat global climate change. Yet there is still strong resistance to such expansion, and much of that is based on the issue of how to safely dispose of the resulting radioactive waste material. MIT recently convened a workshop to help nuclear engineers, policymakers, and academics learn about approaches to communicating accurate information about the management of nuclear waste to students and the public, in hopes of allaying fears and encouraging support for the development of new, safer nuclear power plants around the world.

      Organized by Haruko Wainwright, an MIT assistant professor of nuclear science and engineering and of civil and environmental engineering, the workshop included professors, researchers, industry representatives, and government officials, and was designed to emphasize the multidisciplinary nature of the issue. MIT News asked Wainwright to describe the workshop and its conclusions, which she reported on in a paper just published in the Journal of Environmental Radioactivity.

      Q: What was the main objective of the this workshop?

      A: There is a growing concern that, in spite of much excitement about new nuclear reactor deployment and nuclear energy for tackling climate change, relatively less attention is being paid to the thorny question of long-term management of the spent fuel (waste) from these reactors. The government and industry have embraced consent-based siting approaches — that is, finding sites to store and dispose nuclear waste through broad community participation with equity and environmental justice considered. However, many of us in academia feel that those in the industry are missing key facts to communicate to the public.

      Understanding and managing nuclear waste requires a multidisciplinary expertise in nuclear, civil, and chemical engineering as well as environmental and earth sciences. For example, the amount of waste per se, which is always very small for nuclear systems, is not the only factor determining the environmental impacts because some radionuclides in the waste are vastly more mobile than others, and thus can spread farther and more quickly. Nuclear engineers, environmental scientists, and others need to work together to predict the environmental impacts of radionuclides in the waste generated by the new reactors, and to develop waste isolation strategies for an extended time.

      We organized this workshop to ensure this collaborative approach is mastered from the start. A second objective was to develop a blueprint for educating next-generation engineers and scientists about nuclear waste and shaping a more broadly educated group of nuclear and general engineers.

      Q: What kinds of innovative teaching practices were discussed and recommended, and are there examples of these practices in action?

       A: Some participants teach project-based or simulation-based courses of real-world situations. For example, students are divided into several groups representing various stakeholders — such as the public, policymakers, scientists, and governments — and discuss the potential siting of a nuclear waste repository in a community. Such a course helps the students to consider the perspectives of different groups, understand a plurality of points of view, and learn how to communicate their ideas and concerns effectively. Other courses may ask students to synthesize key technical facts and numbers, and to develop a Congressional testimony statement or an opinion article for newspapers. 

      Q: What are some of the biggest misconceptions people have about nuclear waste, and how do you think these misconceptions can be addressed?

      A: The workshop participants agreed that the broader and life-cycle perspectives are important. Within the nuclear energy life cycle, for example, people focus disproportionally on high-level radioactive waste or spent fuel, which has been highly regulated and well managed. Nuclear systems also produce secondary waste, including low-level waste and uranium mining waste, which gets less attention.

      The participants also believe that the nuclear industry has been exemplary in leading the environmental and waste isolation science and technologies. Nuclear waste disposal strategies were developed in the 1950s, much earlier than other hazardous waste which began to receive serious regulation only in the 1970s. In addition, current nuclear waste disposal practices consider the compliance periods of isolation for thousands of years, while other hazardous waste disposal is not required to consider beyond 30 years, although some waste has an essentially infinite longevity, for example, mercury or lead. Finally, there is relatively unregulated waste — such as CO2 from fossil energy, agricultural effluents and other sources — that is released freely into the biosphere and is already impacting our environment. Yet, many people remain more concerned about the relatively well-regulated nuclear waste than about all these unregulated sources.

      Interestingly, many engineers — even nuclear engineers — do not know these facts. We believe that we need to teach students not just cutting-edge technologies, but also broader perspectives, including the history of industries and regulations, as well as environmental science.

      At the same time, we need to move the nuclear community to think more holistically about waste and its environmental impacts from the early stages of design of nuclear systems. We should design new reactors from the “waste up.”  We believe that the nuclear industry should continue to lead waste-management technologies and strategies, and also encourage other industries to adopt lifecycle approaches about their own waste to improve the overall sustainability. More

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      Printing a new approach to fusion power plant materials

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      When Alexander O’Brien sent in his application for graduate school at MIT’s Department of Nuclear Science and Engineering, he had a germ of a research idea already brewing. So when he received a phone call from Professor Mingda Li, he shared it: The student from Arkansas wanted to explore the design of materials that could hold nuclear reactors together.

      Li listened to him patiently and then said, “I think you’d be a really good fit for Professor Ju Li,” O’Brien remembers. Ju Li, the Battelle Energy Alliance Professor in Nuclear Engineering, had wanted to explore 3D printing for nuclear reactors and O’Brien seemed like the right candidate. “At that moment I decided to go to MIT if they accepted me,” O’Brien remembers.

      And they did.

      Under the advisement of Ju Li, the fourth-year doctoral student now explores 3D printing of ceramic-metal composites, materials that can be used to construct fusion power plants.

      An early interest in the sciences

      Growing up in Springdale, Arkansas as a self-described “band nerd,” O’Brien was particularly interested in chemistry and physics. It was one thing to mix baking soda and vinegar to make a “volcano” and quite another to understand why that was happening. “I just enjoyed understanding things on a deeper level and being able to figure out how the world works,” he says.

      At the same time, it was difficult to ignore the economics of energy playing out in his own backyard. When Arkansas, a place that had hardly ever seen earthquakes, started registering them in the wake of fracking in neighboring Oklahoma, it was “like a lightbulb moment” for O’Brien. “I knew this was going to create problems down the line, I knew there’s got to be a better way to do [energy],” he says.

      With the idea of energy alternatives simmering on the back burner, O’Brien enrolled for undergraduate studies at the University of Arkansas. He participated in the school’s marching band — “you show up a week before everyone else and there’s 400 people who automatically become your friends” — and enjoyed the social environment that a large state school could offer.

      O’Brien double-majored in chemical engineering and physics and appreciated “the ability to get your hands dirty on machinery to make things work.” Deciding to begin exploring his interest in energy alternatives, O’Brien researched transition metal dichalcogenides, coatings of which could catalyze the hydrogen evolution reaction and more easily create hydrogen gas, a green energy alternative.

      It was shortly after his sophomore year, however, that O’Brien really found his way in the field of energy alternatives — in nuclear engineering. The American Chemical Society was soliciting student applications for summer study of nuclear chemistry in San Jose, California. O’Brien applied and got accepted. “After years of knowing I wanted to work in green energy but not knowing what that looked like, I very quickly fell in love with [nuclear engineering],” he says. That summer also cemented O’Brien’s decision to attend graduate school. “I came away with this idea of ‘I need to go to grad school because I need to know more about this,’” he says.

      O’Brien especially appreciated an independent project, assigned as part of the summer program: He chose to research nuclear-powered spacecraft. In digging deeper, O’Brien discovered the challenges of powering spacecraft — nuclear was the most viable alternative, but it had to work around extraneous radiation sources in space. Getting to explore national laboratories near San Jose sealed the deal. “I got to visit the National Ignition Facility, which is the big fusion center up there, and just seeing that massive facility entirely designed around this one idea of fusion was kind of mind-blowing to me,” O’Brien says.

      A fresh blueprint for fusion power plants

      O’Brien’s current research at MIT’s Department of Nuclear Science and Engineering (NSE) is equally mind-blowing.

      As the design of new fusion devices kicks into gear, it’s becoming increasingly apparent that the materials we have been using just don’t hold up to the higher temperatures and radiation levels in operating environments, O’Brien says. Additive manufacturing, another term for 3D printing, “opens up a whole new realm of possibilities for what you can do with metals, which is exactly what you’re going to need [to build the next generation of fusion power plants],” he says.

      Metals and ceramics by themselves might not do the job of withstanding high temperatures (750 degrees Celsius is the target) and stresses and radiation, but together they might get there. Although such metal matrix composites have been around for decades, they have been impractical for use in reactors because they’re “difficult to make with any kind of uniformity and really limited in size scale,” O’Brien says. That’s because when you try to place ceramic nanoparticles into a pool of molten metal, they’re going to fall out in whichever direction they want. “3D printing quickly changes that story entirely, to the point where if you want to add these nanoparticles in very specific regions, you have the capability to do that,” O’Brien says.

      O’Brien’s work, which forms the basis of his doctoral thesis and a research paper in the journal Additive Manufacturing, involves implanting metals with ceramic nanoparticles. The net result is a metal matrix composite that is an ideal candidate for fusion devices, especially for the vacuum vessel component, which must be able to withstand high temperatures, extremely corrosive molten salts, and internal helium gas from nuclear transmutation.

      O’Brien’s work focuses on nickel superalloys like Inconel 718, which are especially robust candidates because they can withstand higher operating temperatures while retaining strength. Helium embrittlement, where bubbles of helium caused by fusion neutrons lead to weakness and failure, is a problem with Inconel 718, but composites exhibit potential to overcome this challenge.

      To create the composites, first a mechanical milling process coats the ceramic onto the metal particles. The ceramic nanoparticles act as reinforcing strength agents, especially at high temperatures, and make materials last longer. The nanoparticles also absorb helium and radiation defects when uniformly dispersed, which prevent these damage agents from all getting to the grain boundaries.

      The composite then goes through a 3D printing process called powder bed fusion (non-nuclear fusion), where a laser passes over a bed of this powder melting it into desired shapes. “By coating these particles with the ceramic and then only melting very specific regions, we keep the ceramics in the areas that we want, and then you can build up and have a uniform structure,” O’Brien says.

      Printing an exciting future

      The 3D printing of nuclear materials exhibits such promise that O’Brien is looking at pursuing the prospect after his doctoral studies. “The concept of these metal matrix composites and how they can enhance material property is really interesting,” he says. Scaling it up commercially through a startup company is on his radar.

      For now, O’Brien is enjoying research and catching an occasional Broadway show with his wife. While the band nerd doesn’t pick up his saxophone much anymore, he does enjoy driving up to New Hampshire and going backpacking. “That’s my newfound hobby,” O’Brien says, “since I started grad school.” More

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      in Energy

      A new mathematical “blueprint” is accelerating fusion device development

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      Developing commercial fusion energy requires scientists to understand sustained processes that have never before existed on Earth. But with so many unknowns, how do we make sure we’re designing a device that can successfully harness fusion power?

      We can fill gaps in our understanding using computational tools like algorithms and data simulations to knit together experimental data and theory, which allows us to optimize fusion device designs before they’re built, saving much time and resources.

      Currently, classical supercomputers are used to run simulations of plasma physics and fusion energy scenarios, but to address the many design and operating challenges that still remain, more powerful computers are a necessity, and of great interest to plasma researchers and physicists.

      Quantum computers’ exponentially faster computing speeds have offered plasma and fusion scientists the tantalizing possibility of vastly accelerated fusion device development. Quantum computers could reconcile a fusion device’s many design parameters — for example, vessel shape, magnet spacing, and component placement — at a greater level of detail, while also completing the tasks faster. However, upgrading to a quantum computer is no simple task.

      In a paper, “Dyson maps and unitary evolution for Maxwell equations in tensor dielectric media,” recently published in Physics Review A, Abhay K. Ram, a research scientist at the MIT Plasma Science and Fusion Center (PSFC), and his co-authors Efstratios Koukoutsis, Kyriakos Hizanidis, and George Vahala present a framework that would facilitate the use of quantum computers to study electromagnetic waves in plasma and its manipulation in magnetic confinement fusion devices.

      Quantum computers excel at simulating quantum physics phenomena, but many topics in plasma physics are predicated on the classical physics model. A plasma (which is the “dielectric media” referenced in the paper’s title) consists of many particles — electrons and ions — the collective behaviors of which are effectively described using classic statistical physics. In contrast, quantum effects that influence atomic and subatomic scales are averaged out in classical plasma physics.  

      Furthermore, the descriptive limitations of quantum mechanics aren’t suited to plasma. In a fusion device, plasmas are heated and manipulated using electromagnetic waves, which are one of the most important and ubiquitous occurrences in the universe. The behaviors of electromagnetic waves, including how waves are formed and interact with their surroundings, are described by Maxwell’s equations — a foundational component of classical plasma physics, and of general physics as well. The standard form of Maxwell’s equations is not expressed in “quantum terms,” however, so implementing the equations on a quantum computer is like fitting a square peg in a round hole: it doesn’t work.

      Consequently, for plasma physicists to take advantage of quantum computing’s power for solving problems, classical physics must be translated into the language of quantum mechanics. The researchers tackled this translational challenge, and in their paper, they reveal that a Dyson map can bridge the translational divide between classical physics and quantum mechanics. Maps are mathematical functions that demonstrate how to take an input from one kind of space and transform it to an output that is meaningful in a different kind of space. In the case of Maxwell’s equations, a Dyson map allows classical electromagnetic waves to be studied in the space utilized by quantum computers. In essence, it reconfigures the square peg so it will fit into the round hole without compromising any physics.

      The work also gives a blueprint of a quantum circuit encoded with equations expressed in quantum bits (“qubits”) rather than classical bits so the equations may be used on quantum computers. Most importantly, these blueprints can be coded and tested on classical computers.

      “For years we have been studying wave phenomena in plasma physics and fusion energy science using classical techniques. Quantum computing and quantum information science is challenging us to step out of our comfort zone, thereby ensuring that I have not ‘become comfortably numb,’” says Ram, quoting a Pink Floyd song.

      The paper’s Dyson map and circuits have put quantum computing power within reach, fast-tracking an improved understanding of plasmas and electromagnetic waves, and putting us that much closer to the ideal fusion device design.    More

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      in Energy

      Understanding boiling to help the nuclear industry and space missions

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      To launch extended missions in space, the National Aeronautics and Space Administration (NASA) is borrowing a page from the nuclear engineering industry: It is trying to understand how boiling works.

      Planning for long-term missions has NASA researching ways of packing the least amount of cryogenic fuel possible for efficient liftoff. One potential solution is to refuel the rocket in space using fuel depots placed in low Earth orbits. This way, the spacecraft can carry the lightest fuel load — enough to reach the low Earth orbit to refuel as necessary and complete the mission. But refueling in space requires a thorough knowledge of cryogenic fuels.

      “We [need to understand] how boiling of cryogens behaves in microgravity conditions [encountered in space],” says Florian Chavagnat, a sixth-year doctoral candidate in the Department of Nuclear Science and Engineering (NSE). After all, understanding how cryogens boil in space is critical to NASA’s fuel management strategy. The vast majority of studies on boiling evaluate fluids that boil at high temperatures, which doesn’t necessarily apply to cryogens. Under the advisement of Matteo Bucci and Emilio Baglietto, Chavagnat is working on NASA-sponsored research about cryogens and the way the lack of buoyancy in space affects boiling.

      A childhood spent tinkering

      A deep understanding of engineering and physical phenomena is exactly what Chavagnat developed growing up in Boussy-Saint-Antoine, a suburb of Paris, with parents who worked for SNCF, the national state-owned rail company. Chavagnat remembers discussing the working of trains and motors with his engineer dad and building a variety of balsa-wood models. One of his memorable projects was a sailboat propelled by a motor from an electric toothbrush.

      By the time he was a teenager, Chavagnat received a metal lathe as a gift. His tinkering became an obsession; a compressed air engine was a favorite project. Soon his parents’ small shed, meant for gardening, became a factory, Chavagnat recalls, laughing.

      A lifelong love of math and physics propelled a path to the National Institute of Applied Science in Rouen, Normandy, where Chavagnat studied energetics and propulsion as part of a five-year engineering program. In his final year, Chavagnat studied atomic engineering from INSTN Paris-Saclay, part of the esteemed French Alternative Energies and Atomic Energy Commission (CEA).

      The final year of studies at CEA required a six-month-long internship, which traditionally sets the course for a job. Chavagnat decided to take a chance and apply for an internship at MIT NSE instead, knowing his future course might be uncertain. “I didn’t take a lot of risk in my life, but this one was a big risk,” Chavagnat says. The gamble paid off: Chavagnat won the internship with Charles Forsberg, which paved the way for his admission as a doctoral student. “I selected MIT because it has always been my dream school,” Chavagnat says. He also enjoyed the idea of challenging himself to improve his English-speaking skills.

      A love of physics and heat transfer

      Chavagnat loves physics — “if I can study any problem in physics, I’d be happy” he says — which led him to working on heat transfer, more specifically on boiling heat transfer. His early doctoral research focused on transient boiling in nuclear reactors, part of which has been published in the International Journal of Heat and Mass Transfer.

      Chavagnat’s research targets a specific kind of nuclear reactor called a material test reactor (MTR). Nuclear scientists use MTRs to understand how materials used in plant operations might behave under long-term use. Densely packed nuclear fuel, running at high power, simulates long-term effects using a very intense neutron flux.

      To prevent failure, operators limit reactor temperature by flowing very cold water at high velocity. When reactor heat power increases uncontrollably, the piped water begins to boil. Boiling works to prevent meltdown by altering neutron moderation and extracting heat from the fuel. “[Unfortunately], that only works until you reach a certain heat flux at the fuel cladding, after which the efficiency completely drops,” Chavagnat says. Once the critical heat flux is reached, water vapor starts to blanket and insulate the fuel elements, leading to rapidly rising cladding temperatures and potential burnout.

      The key is to figure out the behavior of maximum boiling heat flux under routine MTR conditions — cold water, high flow velocity, and narrow spacing between the fuel elements.

      Study of cryogenic boiling

      Boiling continues to occupy center stage as Chavagnat pursues the question for NASA. Cryogens boil at very low temperatures, so the question of how to prevent fuel loss from routine space-based operations is an important one to answer.

      Chavagnat is studying how boiling would behave under reduced or absent buoyancy, which are the conditions cryogenic rocket fuel will encounter in space.

      To reproduce space-like conditions on Earth, buoyancy can be modified without going to space. Chavagnat is manipulating the inclination of the boiling surface — placing it upside down is an example — such that buoyancy does not do what it usually does: help bubbles break away from the surface. He is also performing boiling experiments in parabolic flights to simulate microgravity, similar to what is experienced aboard the International Space Station.

      Chavagnat designed and built equipment which can perform both methods with minimum changes. “We observed nitrogen boiling on our surface by imaging it using two high-speed video cameras,” he says. The experiment was approved to go on board the parabolic flights operated by Zero-G, a company that operates weightless flights. The team successfully completed four parabolic flights in 2022.

      “Flying an experiment aboard an aircraft and operating it in microgravity is an incredible experience, but is challenging,” Chavagnat says, “Knowing the details the experiment is a must, but other skills are quite useful — in particular, working as a team, being able to manage high stress levels, and being able to work while being motion-sick.” Another challenge is that the majority of issues cannot be fixed once aboard, as aircraft pilots perform the parabola (each lasting 17 seconds) almost back-to-back.

      Throughout his research at MIT, Chavagnat has been captivated by how complex a simple phenomenon like boiling can truly be. “In your childhood, you have a certain idea of how boiling looks, relatively slow bubbles that you can see with the naked eye,” he says, “but you don’t realize the complexity until you see it with your own eyes.”

      In his infrequent spare time, Chavagnat plays soccer with the NSE’s team, the Atom Smashers. The group meets only five times a semester so it’s a low-key commitment, says Chavagnat who spends most of his time at the lab. “I am doing mostly experiments at MIT; it turns out the skills I learned in my shed when I was 15 are actually quite useful here,” he laughs. More

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      in Environment

      Exploring the bow shock and beyond

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      For most people, the night sky conjures a sense of stillness, an occasional shooting star the only visible movement. A conversation with Rishabh Datta, however, unveils the supersonic drama crashing above planet Earth. The PhD candidate has focused his recent study on the plasma speeding through space, flung from sources like the sun’s corona and headed toward Earth, halted abruptly by colliding with the planet’s magnetosphere. The resulting shock wave is similar to the “bow shock” that forms around the nose cone of a supersonic jet, which manifests as the familiar sonic boom.

      The bow shock phenomenon has been well studied. “It’s probably one of the things that’s keeping life alive,” says Datta, “protecting us from the solar wind.” While he feels the magnetosphere provides “a very interesting space laboratory,” Datta’s main focus is, “Can we create this high-energy plasma that is moving supersonically in a laboratory, and can we study it? And can we learn things that are hard to diagnose in an astrophysical plasma?”

      Datta’s research journey to the bow shock and beyond began when he joined a research program for high school students at the National University Singapore. Tasked with culturing bacteria and measuring the amount of methane they produced in a biogas tank, Datta found his first research experience “quite nasty.”

      “I was working with chicken manure, and every day I would come home smelling completely awful,” he says.

      As an undergraduate at Georgia Tech, Datta’s interests turned toward solar power, compelled by a new technology he felt could generate sustainable energy. By the time he joined MIT’s Department of Mechanical Engineering, though, his interests had morphed into researching the heat and mass transfer from airborne droplets. After a year of study, he felt the need to go in a yet another direction.

      The subject of astrophysical plasmas had recently piqued his interest, and he followed his curiosity to Department of Nuclear Science and Engineering Professor Nuno Loureiro’s introductory plasma class. There he encountered Professor Jack Hare, who was sitting in on the class and looking for students to work with him.

      “And that’s how I ended up doing plasma physics and studying bow shocks,” he says, “a long and circuitous route that started with culturing bacteria.”

      Gathering measurements from MAGPIE

      Datta is interested in what he can learn about plasma from gathering measurements of a laboratory-created bow shock, seeking to verify theoretical models. He uses data already collected from experiments on a pulsed-power generator known as MAGPIE (the Mega-Ampere Generator of Plasma Implosion Experiments), located at Imperial College, London. By observing how long it takes a plasma to reach an obstacle, in this case a probe that measures magnetic fields, Datta was able to determine its velocity.   

      With the velocity established, an interferometry system was able to provide images of the probe and the plasma around it, allowing Datta to characterize the structure of the bow shock.

      “The shape depends on how fast sound waves can travel in a plasma,” says Datta. “And this ‘sound speed’ depends on the temperature.”

      The interdependency of these characteristics means that by imaging a shock it’s possible to determine temperature, sound speed, and other measurements more easily and cheaply than with other methods.

      “And knowing more about your plasma allows you to make predictions about, for example, electrical resistivity, which can be important for understanding other physics that might interest you,” says Datta, “like magnetic reconnection.”

      This phenomenon, which controls the evolution of such violent events as solar flares, coronal mass ejections, magnetic storms that drive auroras, and even disruptions in fusion tokamaks, has become the focus of his recent research. It happens when opposing magnetic fields in a plasma break and then reconnect, generating vast quantities of heat and accelerating the plasma to high velocities.

      Onward to Z

      Datta travels to Sandia National Laboratories in Albuquerque, New Mexico, to work on the largest pulsed power facility in the world, informally known as “the Z machine,” to research how the properties of magnetic reconnection change when a plasma emits strong radiation and cools rapidly.

      In future years, Datta will only have to travel across Albany Street on the MIT campus to work on yet another machine, PUFFIN, currently being built at the Plasma Science and Fusion Center (PSFC). Like MAGPIE and Z, PUFFIN is a pulsed power facility, but with the ability to drive the current 10 times longer than other machines, opening up new opportunities in high-energy-density laboratory astrophysics.

      Hare, who leads the PUFFIN team, is pleased with Datta’s increasing experience.

      “Working with Rishabh is a real pleasure,” he says, “He has quickly learned the ins and outs of experimental plasma physics, often analyzing data from machines he hasn’t even yet had the chance to see! While we build PUFFIN it’s really useful for us to carry out experiments at other pulsed-power facilities worldwide, and Rishabh has already written papers on results from MAGPIE, COBRA at Cornell in Ithaca, New York, and the Z Machine.”

      Pursuing climate action at MIT

      Hand-in-hand with Datta’s quest to understand plasma is his pursuit of sustainability, including carbon-free energy solutions. A member of the Graduate Student Council’s Sustainability Committee since he arrived in 2019, he was heartened when MIT, revising their climate action plan, provided him and other students the chance to be involved in decision-making. He led focus groups to provide graduate student input on the plan, raising issues surrounding campus decarbonization, the need to expand hiring of early-career researchers working on climate and sustainability, and waste reduction and management for MIT laboratories.

      When not focused on bringing astrophysics to the laboratory, Datta sometimes experiments in a lab closer to home — the kitchen — where he often challenges himself to duplicate a recipe he has recently tried at a favorite restaurant. His stated ambition could apply to his sustainability work as well as to his pursuit of understanding plasma.

      “The goal is to try and make it better,” he says. “I try my best to get there.”

      Datta’s work has been funded, in part, by the National Science Foundation, National Nuclear Security Administration, and the Department of Energy. More