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    Ian Hutchinson: A lifetime probing plasma, on Earth and in space

    Ordinary folks gazing at the night sky can readily spot Earth’s close neighbors and the light of distant stars. But when Ian Hutchinson scans the cosmos, he takes in a great deal more. There is, for instance, the constant rush of plasma — highly charged ionized gases — from the sun. As this plasma flows by solid bodies such as the moon, it interacts with them electromagnetically, sometimes generating a phenomenon called an electron hole — a perturbation in the gaseous solar tide that forms a solitary, long-lived wave. Hutchinson, a professor in the MIT Department of Nuclear Science and Engineering (NSE), knows they exist because he found a way to measure them.

    “When I look up at the moon with my sweetheart, my wife of 48 years, I imagine that streaming from its dark side are electron holes that my students and I predicted, and that we then discovered,” he says. “It’s quite sentimental to me.”

    Hutchinson’s studies of these wave phenomena, summed up in a paper, “Electron holes in phase space: What they are and why they matter,” recently earned the 2022 Ronald C. Davidson Award for Plasma Physics presented by the American Physical Society’s Division of Plasma Physics.

    Measuring perturbations in plasma

    Hutchinson’s exploration of electron holes was sparked by his work over many decades in fusion energy, another branch of plasma physics. He has made many contributions to the design, operation, and experimental investigation of tokamaks — a toroidal magnetic confinement device — intended to replicate and harness the fiery thermonuclear reactions in the plasma of stars for carbon-free energy on Earth. Hutchinson took a particular interest in how to measure the plasma, notably the flow at the edges of tokamaks.

    Heat generated from fusion reactions may escape magnetic confinement and build up along these edges, leading to potential temperature spikes that impact the performance of the confinement device. Hutchinson discovered how to interpret signals from small probes to measure and track plasma velocity at the tokamak’s edge.

    “My theoretical work also showed that these probes quite likely induce electron holes,” he says. But proving this contention required experiments at resolutions in time and space beyond what tokamaks allow. That’s when Hutchinson had an important insight.

    “I realized that the phenomena we were trying to investigate can actually be measured with exquisite accuracy by satellites that travel through plasma surrounding Earth and other solid bodies,” he says. Although plasmas in space are at a much larger scale than the plasmas generated in the laboratory, measurements of these gases by a satellite is analogous “to a situation where we fly a tiny micron-sized spacecraft through the wakes of probes at the edge of tokamaks,” says Hutchinson.

    Using satellite data provided by NASA, Hutchinson set about analyzing solar plasma as it whips by the moon. “We predicted instabilities and the generation of electron holes,” he recounts. “Our theory passed with flying colors: We saw lots of holes in the wake of the moon, and few elsewhere.”

    Developing tokamaks

    Hutchinson grew up in the English midlands and attended Cambridge University, where he became “intrigued by plasma physics in a course taught by an entertaining and effective teacher,” he says.

    Hutchinson headed for doctoral studies at Australian National University on fellowship. The experience afforded him his first opportunity for research on plasma confinement. “There I was at the ends of the Earth, and I was one of very few scientists worldwide with a tokamak almost to myself,” he says. “It was a device that had risen to the top of everyone’s agenda in fusion research as something we really needed to understand.”

    His dissertation, which examined instabilities in plasma, and his hands-on experience with the device, brought him to the attention of Ronald Parker SM ’63, PhD ’67, now emeritus professor of nuclear science and engineering and electrical engineering and computer science, who was building MIT’s Alcator tokamak program.

    In 1976, Hutchinson joined this group, spending three years as a research scientist. After an interval in Britain, he returned to MIT with a faculty position in NSE, and soon, a leadership role in developing the next phase of the Institute’s fusion experiment, the Alcator-C Mod tokamak.

    “This was a major development of the high-magnetic field approach to fusion,” says Hutchinson. Powerful magnets are essential for containing the superhot plasma; the MIT group developed an experiment with a magnetic field more than 150,000 times the strength of the Earth’s magnetic field. “We were in the business of determining whether tokamaks had sufficiently good confinement to function as fusion reactors,” he says.

    Hutchinson oversaw the nearly six-year construction of the device, which was funded by the U.S. Department of Energy. He then led its operation starting in 1993, creating a national facility for experiments that drew scientists and students from around the world. At the time, it was the largest research group on campus at MIT.

    In their studies, scientists employed novel heating and sustainment techniques using radio waves and microwaves. They also discovered new methods for performing diagnostics inside the tokamak. “Alcator C-Mod demonstrated excellent confinement in a more compact and cost-effective device,” says Hutchinson. “It was unique in the world.”

    Hutchinson is proud of Alcator C-Mod’s technological achievements, including its record for highest plasma pressure for a magnetic confinement device. But this large-scale project holds even greater significance for him. “Alcator C-Mod helped beat a new path in fusion research, and has become the basis for the SPARC tokamak now under construction,” he says.

    SPARC is a compact, high-magnetic field fusion energy device under development through a collaboration between MIT’s Plasma Science and Fusion Center and startup Commonwealth Fusions Systems. Its goal is to demonstrate net energy gain from fusion, prove the viability of fusion as a source of carbon-free energy, and tip the scales in the race against climate change. A number of SPARC’s leaders are students Hutchinson taught. “This is a source of considerable satisfaction,” he says. “Some of their down-to-Earth realism comes from me, and perhaps some of their aspirations have been molded by their work with me.” 

    A new phase

    After leading Alcator C-Mod for 15 years and generating hundreds of journal articles, Hutchinson served as NSE’s department head from 2003 to 2009. He wrote the standard textbook on measuring plasmas, and has more recently written “A Student’s Guide to Numerical Methods” (2015), which evolved from a course he taught to introduce graduate students to computational problem-solving in physics and engineering.

    After this, his 40th year on the MIT faculty, Hutchinson will be stepping back from teaching. “It’s important for new generations of students to be taught by people at the pinnacle of their mental and intellectual capacity, and when you reach my age, you’re aware of the fact that you’re slowing down,” he says.

    Hutchinson’s at no loss for ways to spend his time. As a devout Christian, he speaks and writes about the relationship between religion and science, trying to help skeptics on both sides find common ground. He sings in two choral groups, and is very busy grandparenting four grandsons. For a complete change of pace, Hutchinson goes fly fishing.

    But he still has plans to explore new frontiers in plasma physics. “I’m gratified to say I still do important research,” he says. “I’ve solved most of the problems in electron holes, and now I need to say something about ion holes!” More

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    Strengthening electron-triggered light emission

    The way electrons interact with photons of light is a key part of many modern technologies, from lasers to solar panels to LEDs. But the interaction is inherently a weak one because of a major mismatch in scale: A wavelength of visible light is about 1,000 times larger than an electron, so the way the two things affect each other is limited by that disparity.

    Now, researchers at MIT and elsewhere have come up with an innovative way to make much stronger interactions between photons and electrons possible, in the process producing a hundredfold increase in the emission of light from a phenomenon called Smith-Purcell radiation. The finding has potential implications for both commercial applications and fundamental scientific research, although it will require more years of research to make it practical.

    The findings are reported today in the journal Nature, in a paper by MIT postdocs Yi Yang (now an assistant professor at the University of Hong Kong) and Charles Roques-Carmes, MIT professors Marin Soljačić and John Joannopoulos, and five others at MIT, Harvard University, and Technion-Israel Institute of Technology.

    In a combination of computer simulations and laboratory experiments, the team found that using a beam of electrons in combination with a specially designed photonic crystal — a slab of silicon on an insulator, etched with an array of nanometer-scale holes — they could theoretically predict stronger emission by many orders of magnitude than would ordinarily be possible in conventional Smith-Purcell radiation. They also experimentally recorded a one hundredfold increase in radiation in their proof-of-concept measurements.

    Unlike other approaches to producing sources of light or other electromagnetic radiation, the free-electron-based method is fully tunable — it can produce emissions of any desired wavelength, simply by adjusting the size of the photonic structure and the speed of the electrons. This may make it especially valuable for making sources of emission at wavelengths that are difficult to produce efficiently, including terahertz waves, ultraviolet light, and X-rays.

    The team has so far demonstrated the hundredfold enhancement in emission using a repurposed electron microscope to function as an electron beam source. But they say that the basic principle involved could potentially enable far greater enhancements using devices specifically adapted for this function.

    The approach is based on a concept called flatbands, which have been widely explored in recent years for condensed matter physics and photonics but have never been applied to affecting the basic interaction of photons and free electrons. The underlying principle involves the transfer of momentum from the electron to a group of photons, or vice versa. Whereas conventional light-electron interactions rely on producing light at a single angle, the photonic crystal is tuned in such a way that it enables the production of a whole range of angles.

    The same process could also be used in the opposite direction, using resonant light waves to propel electrons, increasing their velocity in a way that could potentially be harnessed to build miniaturized particle accelerators on a chip. These might ultimately be able to perform some functions that currently require giant underground tunnels, such as the 30-kilometer-wide Large Hadron Collider in Switzerland.

    “If you could actually build electron accelerators on a chip,” Soljačić says, “you could make much more compact accelerators for some of the applications of interest, which would still produce very energetic electrons. That obviously would be huge. For many applications, you wouldn’t have to build these huge facilities.”

    The new system could also potentially provide a highly controllable X-ray beam for radiotherapy purposes, Roques-Carmes says.

    And the system could be used to generate multiple entangled photons, a quantum effect that could be useful in the creation of quantum-based computational and communications systems, the researchers say. “You can use electrons to couple many photons together, which is a considerably hard problem if using a purely optical approach,” says Yang. “That is one of the most exciting future directions of our work.”

    Much work remains to translate these new findings into practical devices, Soljačić cautions. It may take some years to develop the necessary interfaces between the optical and electronic components and how to connect them on a single chip, and to develop the necessary on-chip electron source producing a continuous wavefront, among other challenges.

    “The reason this is exciting,” Roques-Carmes adds, “is because this is quite a different type of source.” While most technologies for generating light are restricted to very specific ranges of color or wavelength, and “it’s usually difficult to move that emission frequency. Here it’s completely tunable. Simply by changing the velocity of the electrons, you can change the emission frequency. … That excites us about the potential of these sources. Because they’re different, they offer new types of opportunities.”

    But, Soljačić concludes, “in order for them to become truly competitive with other types of sources, I think it will require some more years of research. I would say that with some serious effort, in two to five years they might start competing in at least some areas of radiation.”

    The research team also included Steven Kooi at MIT’s Institute for Soldier Nanotechnologies, Haoning Tang and Eric Mazur at Harvard University, Justin Beroz at MIT, and Ido Kaminer at Technion-Israel Institute of Technology. The work was supported by the U.S. Army Research Office through the Institute for Soldier Nanotechnologies, the U.S. Air Force Office of Scientific Research, and the U.S. Office of Naval Research. More

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    Manufacturing a cleaner future

    Manufacturing had a big summer. The CHIPS and Science Act, signed into law in August, represents a massive investment in U.S. domestic manufacturing. The act aims to drastically expand the U.S. semiconductor industry, strengthen supply chains, and invest in R&D for new technological breakthroughs. According to John Hart, professor of mechanical engineering and director of the Laboratory for Manufacturing and Productivity at MIT, the CHIPS Act is just the latest example of significantly increased interest in manufacturing in recent years.

    “You have multiple forces working together: reflections from the pandemic’s impact on supply chains, the geopolitical situation around the world, and the urgency and importance of sustainability,” says Hart. “This has now aligned incentives among government, industry, and the investment community to accelerate innovation in manufacturing and industrial technology.”

    Hand-in-hand with this increased focus on manufacturing is a need to prioritize sustainability.

    Roughly one-quarter of greenhouse gas emissions came from industry and manufacturing in 2020. Factories and plants can also deplete local water reserves and generate vast amounts of waste, some of which can be toxic.

    To address these issues and drive the transition to a low-carbon economy, new products and industrial processes must be developed alongside sustainable manufacturing technologies. Hart sees mechanical engineers as playing a crucial role in this transition.

    “Mechanical engineers can uniquely solve critical problems that require next-generation hardware technologies, and know how to bring their solutions to scale,” says Hart.

    Several fast-growing companies founded by faculty and alumni from MIT’s Department of Mechanical Engineering offer solutions for manufacturing’s environmental problem, paving the path for a more sustainable future.

    Gradiant: Cleantech water solutions

    Manufacturing requires water, and lots of it. A medium-sized semiconductor fabrication plant uses upward of 10 million gallons of water a day. In a world increasingly plagued by droughts, this dependence on water poses a major challenge.

    Gradiant offers a solution to this water problem. Co-founded by Anurag Bajpayee SM ’08, PhD ’12 and Prakash Govindan PhD ’12, the company is a pioneer in sustainable — or “cleantech” — water projects.

    As doctoral students in the Rohsenow Kendall Heat Transfer Laboratory, Bajpayee and Govindan shared a pragmatism and penchant for action. They both worked on desalination research — Bajpayee with Professor Gang Chen and Govindan with Professor John Lienhard.

    Inspired by a childhood spent during a severe drought in Chennai, India, Govindan developed for his PhD a humidification-dehumidification technology that mimicked natural rainfall cycles. It was with this piece of technology, which they named Carrier Gas Extraction (CGE), that the duo founded Gradiant in 2013.

    The key to CGE lies in a proprietary algorithm that accounts for variability in the quality and quantity in wastewater feed. At the heart of the algorithm is a nondimensional number, which Govindan proposes one day be called the “Lienhard Number,” after his doctoral advisor.

    “When the water quality varies in the system, our technology automatically sends a signal to motors within the plant to adjust the flow rates to bring back the nondimensional number to a value of one. Once it’s brought back to a value of one, you’re running in optimal condition,” explains Govindan, who serves as chief operating officer of Gradiant.

    This system can treat and clean the wastewater produced by a manufacturing plant for reuse, ultimately conserving millions of gallons of water each year.

    As the company has grown, the Gradiant team has added new technologies to their arsenal, including Selective Contaminant Extraction, a cost-efficient method that removes only specific contaminants, and a brine-concentration method called Counter-Flow Reverse Osmosis. They now offer a full technology stack of water and wastewater treatment solutions to clients in industries including pharmaceuticals, energy, mining, food and beverage, and the ever-growing semiconductor industry.

    “We are an end-to-end water solutions provider. We have a portfolio of proprietary technologies and will pick and choose from our ‘quiver’ depending on a customer’s needs,” says Bajpayee, who serves as CEO of Gradiant. “Customers look at us as their water partner. We can take care of their water problem end-to-end so they can focus on their core business.”

    Gradiant has seen explosive growth over the past decade. With 450 water and wastewater treatment plants built to date, they treat the equivalent of 5 million households’ worth of water each day. Recent acquisitions saw their total employees rise to above 500.

    The diversity of Gradiant’s solutions is reflected in their clients, who include Pfizer, AB InBev, and Coca-Cola. They also count semiconductor giants like Micron Technology, GlobalFoundries, Intel, and TSMC among their customers.

    “Over the last few years, we have really developed our capabilities and reputation serving semiconductor wastewater and semiconductor ultrapure water,” says Bajpayee.

    Semiconductor manufacturers require ultrapure water for fabrication. Unlike drinking water, which has a total dissolved solids range in the parts per million, water used to manufacture microchips has a range in the parts per billion or quadrillion.

    Currently, the average recycling rate at semiconductor fabrication plants — or fabs — in Singapore is only 43 percent. Using Gradiant’s technologies, these fabs can recycle 98-99 percent of the 10 million gallons of water they require daily. This reused water is pure enough to be put back into the manufacturing process.

    “What we’ve done is eliminated the discharge of this contaminated water and nearly eliminated the dependence of the semiconductor fab on the public water supply,” adds Bajpayee.

    With new regulations being introduced, pressure is increasing for fabs to improve their water use, making sustainability even more important to brand owners and their stakeholders.

    As the domestic semiconductor industry expands in light of the CHIPS and Science Act, Gradiant sees an opportunity to bring their semiconductor water treatment technologies to more factories in the United States.

    Via Separations: Efficient chemical filtration

    Like Bajpayee and Govindan, Shreya Dave ’09, SM ’12, PhD ’16 focused on desalination for her doctoral thesis. Under the guidance of her advisor Jeffrey Grossman, professor of materials science and engineering, Dave built a membrane that could enable more efficient and cheaper desalination.

    A thorough cost and market analysis brought Dave to the conclusion that the desalination membrane she developed would not make it to commercialization.

    “The current technologies are just really good at what they do. They’re low-cost, mass produced, and they worked. There was no room in the market for our technology,” says Dave.

    Shortly after defending her thesis, she read a commentary article in the journal Nature that changed everything. The article outlined a problem. Chemical separations that are central to many manufacturing processes require a huge amount of energy. Industry needed more efficient and cheaper membranes. Dave thought she might have a solution.

    After determining there was an economic opportunity, Dave, Grossman, and Brent Keller PhD ’16 founded Via Separations in 2017. Shortly thereafter, they were chosen as one of the first companies to receive funding from MIT’s venture firm, The Engine.

    Currently, industrial filtration is done by heating chemicals at very high temperatures to separate compounds. Dave likens it to making pasta by boiling all of the water off until it evaporates and all you are left with is the pasta noodles. In manufacturing, this method of chemical separation is extremely energy-intensive and inefficient.

    Via Separations has created the chemical equivalent of a “pasta strainer.” Rather than using heat to separate, their membranes “strain” chemical compounds. This method of chemical filtration uses 90 percent less energy than standard methods.

    While most membranes are made of polymers, Via Separations’ membranes are made with graphene oxide, which can withstand high temperatures and harsh conditions. The membrane is calibrated to the customer’s needs by altering the pore size and tuning the surface chemistry.

    Currently, Dave and her team are focusing on the pulp and paper industry as their beachhead market. They have developed a system that makes the recovery of a substance known as “black liquor” more energy efficient.

    “When tree becomes paper, only one-third of the biomass is used for the paper. Currently the most valuable use for the remaining two-thirds not needed for paper is to take it from a pretty dilute stream to a pretty concentrated stream using evaporators by boiling off the water,” says Dave.

    This black liquor is then burned. Most of the resulting energy is used to power the filtration process.

    “This closed-loop system accounts for an enormous amount of energy consumption in the U.S. We can make that process 84 percent more efficient by putting the ‘pasta strainer’ in front of the boiler,” adds Dave.

    VulcanForms: Additive manufacturing at industrial scale

    The first semester John Hart taught at MIT was a fruitful one. He taught a course on 3D printing, broadly known as additive manufacturing (AM). While it wasn’t his main research focus at the time, he found the topic fascinating. So did many of the students in the class, including Martin Feldmann MEng ’14.

    After graduating with his MEng in advanced manufacturing, Feldmann joined Hart’s research group full time. There, they bonded over their shared interest in AM. They saw an opportunity to innovate with an established metal AM technology, known as laser powder bed fusion, and came up with a concept to realize metal AM at an industrial scale.

    The pair co-founded VulcanForms in 2015.

    “We have developed a machine architecture for metal AM that can build parts with exceptional quality and productivity,” says Hart. “And, we have integrated our machines in a fully digital production system, combining AM, postprocessing, and precision machining.”

    Unlike other companies that sell 3D printers for others to produce parts, VulcanForms makes and sells parts for their customers using their fleet of industrial machines. VulcanForms has grown to nearly 400 employees. Last year, the team opened their first production factory, known as “VulcanOne,” in Devens, Massachusetts.

    The quality and precision with which VulcanForms produces parts is critical for products like medical implants, heat exchangers, and aircraft engines. Their machines can print layers of metal thinner than a human hair.

    “We’re producing components that are difficult, or in some cases impossible to manufacture otherwise,” adds Hart, who sits on the company’s board of directors.

    The technologies developed at VulcanForms may help lead to a more sustainable way to manufacture parts and products, both directly through the additive process and indirectly through more efficient, agile supply chains.

    One way that VulcanForms, and AM in general, promotes sustainability is through material savings.

    Many of the materials VulcanForms uses, such as titanium alloys, require a great deal of energy to produce. When titanium parts are 3D-printed, substantially less of the material is used than in a traditional machining process. This material efficiency is where Hart sees AM making a large impact in terms of energy savings.

    Hart also points out that AM can accelerate innovation in clean energy technologies, ranging from more efficient jet engines to future fusion reactors.

    “Companies seeking to de-risk and scale clean energy technologies require know-how and access to advanced manufacturing capability, and industrial additive manufacturing is transformative in this regard,” Hart adds.

    LiquiGlide: Reducing waste by removing friction

    There is an unlikely culprit when it comes to waste in manufacturing and consumer products: friction. Kripa Varanasi, professor of mechanical engineering, and the team at LiquiGlide are on a mission to create a frictionless future, and substantially reduce waste in the process.

    Founded in 2012 by Varanasi and alum David Smith SM ’11, LiquiGlide designs custom coatings that enable liquids to “glide” on surfaces. Every last drop of a product can be used, whether it’s being squeezed out of a tube of toothpaste or drained from a 500-liter tank at a manufacturing plant. Making containers frictionless substantially minimizes wasted product, and eliminates the need to clean a container before recycling or reusing.

    Since launching, the company has found great success in consumer products. Customer Colgate utilized LiquiGlide’s technologies in the design of the Colgate Elixir toothpaste bottle, which has been honored with several industry awards for design. In a collaboration with world- renowned designer Yves Béhar, LiquiGlide is applying their technology to beauty and personal care product packaging. Meanwhile, the U.S. Food and Drug Administration has granted them a Device Master Filing, opening up opportunities for the technology to be used in medical devices, drug delivery, and biopharmaceuticals.

    In 2016, the company developed a system to make manufacturing containers frictionless. Called CleanTanX, the technology is used to treat the surfaces of tanks, funnels, and hoppers, preventing materials from sticking to the side. The system can reduce material waste by up to 99 percent.

    “This could really change the game. It saves wasted product, reduces wastewater generated from cleaning tanks, and can help make the manufacturing process zero-waste,” says Varanasi, who serves as chair at LiquiGlide.

    LiquiGlide works by creating a coating made of a textured solid and liquid lubricant on the container surface. When applied to a container, the lubricant remains infused within the texture. Capillary forces stabilize and allow the liquid to spread on the surface, creating a continuously lubricated surface that any viscous material can slide right down. The company uses a thermodynamic algorithm to determine the combinations of safe solids and liquids depending on the product, whether it’s toothpaste or paint.

    The company has built a robotic spraying system that can treat large vats and tanks at manufacturing plants on site. In addition to saving companies millions of dollars in wasted product, LiquiGlide drastically reduces the amount of water needed to regularly clean these containers, which normally have product stuck to the sides.

    “Normally when you empty everything out of a tank, you still have residue that needs to be cleaned with a tremendous amount of water. In agrochemicals, for example, there are strict regulations about how to deal with the resulting wastewater, which is toxic. All of that can be eliminated with LiquiGlide,” says Varanasi.

    While the closure of many manufacturing facilities early in the pandemic slowed down the rollout of CleanTanX pilots at plants, things have picked up in recent months. As manufacturing ramps up both globally and domestically, Varanasi sees a growing need for LiquiGlide’s technologies, especially for liquids like semiconductor slurry.

    Companies like Gradiant, Via Separations, VulcanForms, and LiquiGlide demonstrate that an expansion in manufacturing industries does not need to come at a steep environmental cost. It is possible for manufacturing to be scaled up in a sustainable way.

    “Manufacturing has always been the backbone of what we do as mechanical engineers. At MIT in particular, there is always a drive to make manufacturing sustainable,” says Evelyn Wang, Ford Professor of Engineering and former head of the Department of Mechanical Engineering. “It’s amazing to see how startups that have an origin in our department are looking at every aspect of the manufacturing process and figuring out how to improve it for the health of our planet.”

    As legislation like the CHIPS and Science Act fuels growth in manufacturing, there will be an increased need for startups and companies that develop solutions to mitigate the environmental impact, bringing us closer to a more sustainable future. More

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    Evelyn Wang appointed as director of US Department of Energy’s Advanced Research Projects Agency-Energy

    On Thursday, the United States Senate confirmed the appointment of Evelyn Wang, the Ford Professor of Engineering and head of the Department of Mechanical Engineering, as director of the Department of Energy’s (DOE) Advanced Research Projects Agency-Energy (ARPA-E).

    “I am deeply honored by the opportunity to serve as the director of ARPA-E. I’d like to thank President Biden, for his nomination to this important role, and Secretary Granholm, for her confidence in my abilities. I am thrilled to be joining the incredibly talented team at ARPA-E and look forward to helping bring innovative energy technologies that bolster our nation’s economy and national security to market,” says Wang. 

    An internationally recognized leader in applying nanotechnology to heat transfer, Wang has developed a number of high-efficiency, clean energy, and clean water solutions. Wang received a bachelor’s degree in mechanical engineering from MIT in 2000. After receiving her master’s degree and PhD from Stanford University, she returned to MIT as a faculty member in 2007. In 2018, she was named department head of MIT’s Department of Mechanical Engineering.

    As director of ARPA-E, Wang will advance the agency’s mission to fund and support early-stage energy research that has the potential to impact energy generation, storage, and use. The agency helps researchers commercialize innovative technologies that, according to ARPA-E, “have the potential to radically improve U.S. economic prosperity, national security, and environmental well-being.”

    “I am so grateful to the Senate for confirming Dr. Evelyn Wang to serve as Director of DOE’s Advanced Research Projects Agency-Energy,” U.S. Secretary of Energy Jennifer M. Granholm said in a statement today. “Now more than ever, we rely on ARPA-E to support early-stage energy technologies that will help us tackle climate change and strengthen American competitiveness. Dr. Wang’s experience and expertise with groundbreaking research will ensure that ARPA-E continues its role as a key engine of innovation and climate action. I am deeply grateful for Dr. Wang’s willingness to serve the American people, and we’re so excited to welcome her to DOE.” 

    Wang has served as principal investigator of MIT’s Device Research Lab. She and her team have developed a number of devices that offer solutions to the world’s many energy and water challenges. These devices include an aerogel that drastically improves window insulation, a high-efficiency solar powered desalination system, a radiative cooling device that requires no electricity, and a system that pulls potable water out of air, even in arid conditions.

    Throughout her career, Wang has been recognized with multiple awards and honors. In 2021, she was elected as a Fellow of the American Association for the Advancement of Science. She received the American Society of Mechanical Engineering (ASME) Gustus L. Memorial Award for outstanding achievement in mechanical engineering in 2017 and was named an ASME Fellow in 2015. Having mentored and advised hundreds of students at MIT, Wang was honored with a MIT Committed to Caring Award for her commitment to mentoring graduate students. She has also served as co-chair of the inaugural Rising Stars in Mechanical Engineering program to encourage women graduate students and postdocs considering future careers in academia.

    As department head, Wang has led and implemented a variety of strategic research, educational, and community initiatives in MIT’s Department of Mechanical Engineering. Alongside other departmental leaders, she led a focus on groundbreaking research advances that help address several “grand challenges” that our world faces. She worked closely with faculty and teaching staff on developing educational offerings that prepare the next generation of mechanical engineers for the workforce. She also championed new initiatives to make the department a more diverse, equitable, and inclusive community for students, faculty, and staff. 

    Wang, who is stepping down as department head effective immediately in light of her confirmation, will be taking a temporary leave as a faculty member at MIT while she serves in this role. MIT School of Engineering Dean Anantha Chandrakasan will share plans for the search for her replacement with the mechanical engineering community in the coming days.

    Once sworn in, Wang will officially assume her role as director of ARPA-E. More

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    MIT scientists contribute to National Ignition Facility fusion milestone

    On Monday, Dec. 5, at around 1 a.m., a tiny sphere of deuterium-tritium fuel surrounded by a cylindrical can of gold called a hohlraum was targeted by 192 lasers at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in California. Over the course of billionths of a second, the lasers fired, generating X-rays inside the gold can, and imploding the sphere of fuel.

    On that morning, for the first time ever, the lasers delivered 2.1 megajoules of energy and yielded 3.15 megajoules in return, achieving a historic fusion energy gain well above 1 — a result verified by diagnostic tools developed by the MIT Plasma Science and Fusion Center (PSFC). The use of these tools and their importance was referenced by Arthur Pak, a LLNL staff scientist who spoke at a U.S. Department of Energy press event on Dec. 13 announcing the NIF’s success.

    Johan Frenje, head of the PSFC High-Energy-Density Physics division, notes that this milestone “will have profound implications for laboratory fusion research in general.”

    Since the late 1950s, researchers worldwide have pursued fusion ignition and energy gain in a laboratory, considering it one of the grand challenges of the 21st century. Ignition can only be reached when the internal fusion heating power is high enough to overcome the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop that very rapidly increases the plasma temperature. In the case of inertial confinement fusion, the method used at the NIF, ignition can initiate a “fuel burn propagation” into the surrounding dense and cold fuel, and when done correctly, enable fusion-energy gain.

    Frenje and his PSFC division initially designed dozens of diagnostic systems that were implemented at the NIF, including the vitally important magnetic recoil neutron spectrometer (MRS), which measures the neutron energy spectrum, the data from which fusion yield, plasma ion temperature, and spherical fuel pellet compression (“fuel areal density”) can be determined. Overseen by PSFC Research Scientist Maria Gatu Johnson since 2013, the MRS is one of two systems at the NIF relied upon to measure the absolute neutron yield from the Dec. 5 experiment because of its unique ability to accurately interpret an implosion’s neutron signals.

    “Before the announcement of this historic achievement could be made, the LLNL team wanted to wait until Maria had analyzed the MRS data to an adequate level for a fusion yield to be determined,” says Frenje.

    Response around MIT to NIF’s announcement has been enthusiastic and hopeful. “This is the kind of breakthrough that ignites the imagination,” says Vice President for Research Maria Zuber, “reminding us of the wonder of discovery and the possibilities of human ingenuity. Although we have a long, hard path ahead of us before fusion can deliver clean energy to the electrical grid, we should find much reason for optimism in today’s announcement. Innovation in science and technology holds great power and promise to address some of the world’s biggest challenges, including climate change.”

    Frenje also credits the rest of the team at the PSFC’s High-Energy-Density Physics division, the Laboratory for Laser Energetics at the University of Rochester, LLNL, and other collaborators for their support and involvement in this research, as well as the National Nuclear Security Administration of the Department of Energy, which has funded much of their work since the early 1990s. He is also proud of the number of MIT PhDs that have been generated by the High-Energy-Density Physics Division and subsequently hired by LLNL, including the experimental lead for this experiment, Alex Zylstra PhD ’15.

    “This is really a team effort,” says Frenje. “Without the scientific dialogue and the extensive know-how at the HEDP Division, the critical contributions made by the MRS system would not have happened.” More

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    Energy, war, and the crisis in Ukraine

    Russia’s invasion of Ukraine is having a global impact on many areas of the world today, affecting the balance of power among states and creating a contest between democratic and authoritarian alliances. It is also having a major impact on the global energy supply. European states have scrambled to reorient their consumption away from Russian natural gas, while Russia has used its energy assets as political leverage while finding new economic partners.

    In short, there is also a battle over energy surrounding the invasion, as a panel of experts analyzed at a public MIT event on Friday. The online discussion, “Energy As a Weapon of War,” was the latest Starr Forum, MIT’s prominent event series on foreign policy and international relations.

    The forum’s two featured speakers both discussed energy issues as well as the larger course of the war. Margarita Balmaceda, a professor of diplomacy and international relations at Seton Hall University and an associate of the Harvard Ukrainian Research Institute, listed three key aspects of the energy issue implicated in the invasion.

    In the first place, she noted, European reliance on Russian natural gas is a long-term issue that also existed with the Russian occupation of Crimea in 2014, but is only now being managed differently.

    “If we look at the case of Germany … you can see that the temptation of this reliance in particular on Russian natural gas was not simply something that you could ascribe to one or two corrupt politicians,” said Balmaceda, author of the book “Russian Energy Chains: The Remaking of Technopolitics from Siberia to Ukraine to the European Union.” Instead, she said, “it’s something that went to all levels of economic life,” including industrial consumers of natural gas, regional governments, and other stakeholders. 

    Secondly, Balmaceda observed, many core manufacturing industries, especially in Germany, have been particularly dependent on Russian energy, making the need for alternatives something that has direct effects in key production sectors.

    “In my view, the real story, and the story we have to pay much more attention to, has to do with … industrial users of natural gas,” Balmaceda said. In fact, she noted, gas consumption is a major part of the production cycle in Europe’s chemical, cement, steel, and paper industries, supporting about 8 million jobs.

    Finally, Balmaceda observed, European boycotts of Russian energy may have temporarily stymied Russia, but the regime has subsequently found new markets in China, India, and elsewhere.

    “It’s very important to understand that this story does not end in the European Union and North America, and if we don’t deal with the real energy concerns of global South countries, we will not get very far in trying to reduce Russia’s energy power moving forward,” she said.

    Constanze Steinmuller, director and Fritz Stern Chair of the Center on the United States and Europe at the Brookings Institution, offered some political context as well as her own perspective on paths forward in the war.

    While policymakers in Europe frequently praise the response of the Biden administration in the U.S., in support of Ukraine, “It’s also remarkable how steadfast the European response has been,” Steinmuller said. She added, “It’s something I was very worried about.” She also praised the German government for “decoupling German dependence from Russian gas and oil imports in ways I honestly would not have thought possible.”

    While the alliance supporting Ukraine has been valuable, Steinmuller said, she believes the U.S. and Europe need to give Ukraine even more backing in terms of weaponry in particular. “It is unclear, at this point still, whether Ukraine will have the means to retain full control over its territory.”

    Meanwhile, Russia’s relationship with China, she added, is profoundly consequential for the long-term trajectory of the war. So far, China has been nominally pledging broad support of Russia while publicly de-escalating the nuclear rhetoric arising from the war. However, Steinmuller added, if China decides to “actively support” Russia militarily, “That would be, I think, the worst game-changer of all, and one that … would be the single greatest challenge that I can envision to our ability to help Ukraine win, and to maintain our own security in Europe.”

    The Starr Forum is organized by MIT’s Center for International Studies (CIS). Friday’s event was co-sponsored by MIT’s Security Studies Program and the MIT-Eurasia program, in addition to CIS.

    The event’s moderators were Elizabeth Wood, a professor of history at MIT, author of the 2016 book “Roots of Russia’s War in Ukraine,” and co-director of the MISTI MIT-Eurasia Program; and Carol Saivetz, a senior advisor in MIT’s Security Studies Program and expert on Soviet and Russian foreign policy. Wood and Saivetz have helped host a series of Starr Forum events over the last year scrutinizing several aspects of Russia’s invasion and Ukraine’s defense.  

    Understanding the role of energy in the war “is obviously of critical importance today,” Wood said in her opening remarks. That includes, she noted, “How energy is being used by Russia as a tool of aggression, how Ukraine is suffering from attacks upon its critical infrastructure, and how the alliance of European [states] and the U.S. is responding.” 

    In response to audience questions, the scholars outlined multiple scenarios in which the war could end, either on more favorable terms for Ukraine or in ways that strengthen Russia. One audience member also queried about the extent to which the current war could also be thought of as a “carbon war, or climate war,” in which a move toward clean energy also lessens global dependence on large gas and oil suppliers, such as Russia.

    In response, Balmaceda noted that the ongoing infrastructure development in Ukraine might, in theory, leave it with no choice but to modernize its energy infrastructure (though its own orientation toward fossil fuels represents just a small portion of global demand). Steinmuller added that “Ukraine will need much more than just to reorient its energy [demand]. … It will have to change its role in the global economy,” given its own industrial reliance on coal and other fossil fuels.

    Overall, Balmaceda added, “Regardless of whether Russia wins this conflict or loses, the rottenness within Russia is deep enough to be bad news for all of us for a long time.” For her part, Steinmuller underscored again how vital increased alliance support would be.

    “We should show that we are willing and able to defend not just a country that has been attacked by a great power, but willing to defend ourselves,” Steinmuller said. Otherwise, she added, “If we didn’t do that, we would have set for all the world to see a precedent of giving in to blackmail, including nuclear blackmail, and allowing this to happen without us being willing to see the defense of Ukraine through to the end.” More

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    Pursuing a practical approach to research

    Koroush Shirvan, the John Clark Hardwick Career Development Professor in the Department of Nuclear Science and Engineering (NSE), knows that the nuclear industry has traditionally been wary of innovations until they are shown to have proven utility. As a result, he has relentlessly focused on practical applications in his research, work that has netted him the 2022 Reactor Technology Award from the American Nuclear Society. “The award has usually recognized practical contributions to the field of reactor design and has not often gone to academia,” Shirvan says.

    One of these “practical contributions” is in the field of accident-tolerant fuels, a program launched by the U.S. Nuclear Regulatory Commission in the wake of the 2011 Fukushima Daiichi incident. The goal within this program, says Shirvan, is to develop new forms of nuclear fuels that can tolerate heat. His team, with students from over 16 countries, is working on numerous possibilities that range in composition and method of production.

    Another aspect of Shirvan’s research focuses on how radiation impacts heat transfer mechanisms in the reactor. The team found fuel corrosion to be the driving force. “[The research] informs how nuclear fuels perform in the reactor, from a practical point of view,” Shirvan says.

    Optimizing nuclear reactor design

    A summer internship when Shirvan was an undergraduate at the University of Florida at Gainesville seeded his drive to focus on practical applications in his studies. A nearby nuclear utility was losing millions because of crud accumulating on fuel rods. Over time, the company was solving the problem by using more fuel, before it had extracted all the life from earlier batches.

    Placement of fuel rods in nuclear reactors is a complex problem with many factors — the life of the fuel, location of hot spots — affecting outcomes. Nuclear reactors change their configuration of fuel rods every 18-24 months to optimize close to 15-20 constraints, leading to roughly 200-800 assemblies. The mind-boggling nature of the problem means that plants have to rely on experienced engineers.

    During his internship, Shirvan optimized the program used to place fuel rods in the reactor. He found that certain rods in assemblies were more prone to the crud deposits, and reworked their configurations, optimizing for these rods’ performance instead of adding assemblies.

    In recent years, Shirvan has applied a branch of artificial intelligence — reinforcement learning — to the configuration problem and created a software program used by the largest U.S. nuclear utility. “This program gives even a layperson the ability to reconfigure the fuels and the reactor without having expert knowledge,” Shirvan says.

    From advanced math to counting jelly beans

    Shirvan’s own expertise in nuclear science and engineering developed quite organically. He grew up in Tehran, Iran, and when he was 14 the family moved to Gainesville, where Shirvan’s aunt and family live. He remembers an awkward couple of years at the new high school where he was grouped in with newly arrived international students, and placed in entry-level classes. “I went from doing advanced mathematics in Iran to counting jelly beans,” he laughs.

    Shirvan applied to the University of Florida for his undergraduate studies since it made economic sense; the school gave full scholarships to Floridian students who received a certain minimum SAT score. Shirvan qualified. His uncle, who was a professor in the nuclear engineering department then, encouraged Shirvan to take classes in the department. Under his uncle’s mentorship, the courses Shirvan took, and his internship, cemented his love of the interdisciplinary approach that the field demanded.

    Having always known that he wanted to teach — he remembers finishing his math tests early in Tehran so he could earn the reward of being class monitor — Shirvan knew graduate school was next. His uncle encouraged him to apply to MIT and to the University of Michigan, home to reputable programs in the field. Shirvan chose MIT because “only at MIT was there a program on nuclear design. There were faculty dedicated to designing new reactors, looking at multiple disciplines, and putting all of that together.” He went on to pursue his master’s and doctoral studies at NSE under the supervision of Professor Mujid Kazimi, focusing on compact pressurized and boiling water reactor designs. When Kazimi passed away suddenly in 2015, Shirvan was a research scientist, and switched to tenure track to guide the professor’s team.

    Another project that Shirvan took in 2015: leadership of MIT’s course on nuclear reactor technology for utility executives. Offered only by the Institute, the program is an introduction to nuclear engineering and safety for personnel who might not have much background in the area. “It’s a great course because you get to see what the real problems are in the energy sector … like grid stability,” Shirvan says.

    A multipronged approach to savings

    Another very real problem nuclear utilities face is cost. Contrary to what one hears on the news, one of the biggest stumbling blocks to building new nuclear facilities in the United States is cost, which today can be up to three times that of renewables, Shirvan says. While many approaches such as advanced manufacturing have been tried, Shirvan believes that the solution to decrease expenditures lies in designing more compact reactors.

    His team has developed an open-source advanced nuclear cost tool and has focused on two different designs: a small water reactor using compact steam technology and a horizontal gas reactor. Compactness also means making fuels more efficient, as Shirvan’s work does, and in improving the heat exchange device. It’s all back to the basics and bringing “commercial viable arguments in with your research,” Shirvan explains.

    Shirvan is excited about the future of the U.S. nuclear industry, and that the 2022 Inflation Reduction Act grants the same subsidies to nuclear as it does for renewables. In this new level playing field, advanced nuclear still has a long way to go in terms of affordability, he admits. “It’s time to push forward with cost-effective design,” Shirvan says, “I look forward to supporting this by continuing to guide these efforts with research from my team.” More

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    Decarbonization amid global crises

    A global pandemic. Russia’s invasion of Ukraine. Inflation. The first-ever serious challenge to the peaceful transfer of power in the United States.

    Forced to face a seemingly unending series of once-in-a-generation crises, how can the world continue to focus attention on goals around carbon emissions and climate change? That was the question posed by Philip R. Sharp, the former president of Resources for the Future and a former 10-term member of the U.S. House of Representatives from Indiana, during his MIT Energy Initiative Fall Colloquium address, entitled “The prospects for decarbonization in America: Will global and domestic crises disrupt our plans?”

    Perhaps surprisingly, Sharp sounded an optimistic note in his answer. Despite deep political divisions in the United States, he noted, Congress has passed five major pieces of legislation — under both presidents Donald Trump and Joseph Biden — aimed at accelerating decarbonization efforts. Rather than hampering movement to combat climate change, Sharp said, domestic and global crises have seemed to galvanize support, create new incentives for action, and even unify political rivals around the cause.

    “Almost everybody is dealing with, to some degree, the absolutely profound, churning events that we are amidst now. Most of them are unexpected, and therefore [we’re] not prepared for [them], and they have had a profound shaking of our thinking,” Sharp said. “The conventional wisdom has not held up in almost all of these areas, and therefore it makes it much more difficult for us to think we know how to predict an uncertain future, and [it causes us to] question our own ability as a nation — or anywhere — to actually take on these challenges. And obviously, climate change is one of the most important.”

    However, Sharp continued, these challenges have, in some instances, spurred action. The war in Ukraine, he noted, has upset European energy markets, but it has also highlighted the importance of countries achieving a more energy-independent posture through renewables. “In America,” he added, “we’ve actually seen absolutely stunning … behavior by the United States Congress, of all places.”

    “What we’ve witnessed is, [Congress] put out incredible … sums of money under the previous administration, and then under this administration, to deal with the Covid crisis,” Sharp added later in his talk. “And then the United States government came together — red and blue — to support the Ukrainians against Russia. It saddens me to say, it seems to take a Russian invasion or the Chinese probing us economically to get us moving. But we are moving, and these things are happening.”

    Congressional action

    Sharp cautioned against getting “caught up” in the familiar viewpoint that Congress, in its current incarnation, is fundamentally incapable of passing meaningful legislation. He pointed, in particular, to the passage of five laws over the previous two years:

    The 2020 Energy Act, which has been characterized as a “down payment on fighting climate change.”
    The Infrastructure Investment and Jobs Act (sometimes called the “bipartisan infrastructure bill”), which calls for investments in passenger rail, electric vehicle infrastructure, electric school buses, and other clean-energy measures;
    The CHIPS and Science Act, a $280 billion effort to revitalize the American semiconductor industry, which some analysts say could direct roughly one-quarter of its funding toward accelerating zero-carbon industries and conducting climate research;
    The Inflation Reduction Act (called by some “the largest climate legislation in U.S. history”), which includes tax credits, incentives, and other provisions to help private companies tackle climate change, increase investments in renewable energy, and enhance energy efficiency; and
    The Kigali Amendment to the Montreal Protocol, ratified by the Senate to little fanfare in September, under which the United States agreed to reduce the consumption and production of hydrofluorocarbons (HFCs).
    “It is a big deal,” Sharp said of the dramatic increase in federal climate action. “It is very significant actions that are being taken — more than what we would expect, or I would expect, out of the Congress at any one time.”

    Along with the many billions of dollars of climate-related investments included in the legislation, Sharp said, these new laws will have a number of positive “spillover” effects.

    “This enables state governments, in their policies, to be more aggressive,” Sharp said. “Why? Because it makes it cheaper for some of the investments that they will try to force within their state.” Another “pretty obvious” spillover effect, Sharp said, is that the new laws will enhance U.S. credibility in international negotiations. Finally, he said, these public investments will make the U.S. economy more competitive in international markets for clean-energy technology — particularly as the United States seeks to compete against China in the space.

    “[Competition with China] has become a motivator in American politics, like it or not,” Sharp said. “There is no question that it is causing and bringing together [politicians] across blue [states] and red [states].”

    Holding onto progress

    Even in an uncertain political climate in which Democrats and Republicans seem unable to agree on basic facts, recent funding commitments are likely to survive, no matter which party controls Congress and the presidency, Sharp said. That’s because most of the legislation relies on broadly popular “carrots” that reward investments in decarbonization, rather than less popular “sticks” that create new restrictions or punishments for companies that fail to decarbonize.

    “Politically, the impact of this is very significant,” Sharp said. “It is so much easier in politics to give away tax [credits] than it is to penalize or put requirements onto people. The fact is that these tax credits are more likely to be politically sustained than other forms of government intervention. That, at least, has been the history.”

    Sharp stressed the importance of what he called “civil society” — institutions such as universities, nonprofits, churches, and other organizations that are apart from government and business — in promoting decarbonization efforts. “[Those groups] can act highly independently, and therefore, they can drive for things that others are not willing to do. Now this does not always work to good purposes. Partly, this diversity and this decentralization in civil society … led to deniers and others being able to stop some climate action. But now my view is, this is starting to all move in the right direction, in a very dynamic and a very important way. What we have seen over the last few years is a big uptick in philanthropy related to climate.”

    Looking ahead

    Sharp’s optimism even extended to the role of social media. He suggested that the “Wild West” era of social platforms may be ending, pointing to the celebrities who have recently lost valuable business partnerships for spreading hate speech and disinformation. “We’re now a lot more alert to the dangers,” he said.

    Some in the audience questioned Sharp about specific paths toward decarbonization, but Sharp said that progress will require a number of disparate approaches — some of which will inevitably have a greater impact than others. “The current policy, and the policy embedded in this [new] legislation … is all about doing both,” he said. “It’s all about advancing [current] technologies into the marketplace, and at the same time driving for breakthroughs.”

    Above all, Sharp stressed the need for continued collective action around climate change. “The fact is, we’re all contributors to some degree,” he said. “But we also all can do something. In my view, this is clearly not a time for hand-wringing. This is a time for action. People have to roll up their sleeves, and go to work, and not roll them down anytime soon.” More