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    Explained: Why perovskites could take solar cells to new heights

    Perovskites hold promise for creating solar panels that could be easily deposited onto most surfaces, including flexible and textured ones. These materials would also be lightweight, cheap to produce, and as efficient as today’s leading photovoltaic materials, which are mainly silicon. They’re the subject of increasing research and investment, but companies looking to harness their potential do have to address some remaining hurdles before perovskite-based solar cells can be commercially competitive.

    The term perovskite refers not to a specific material, like silicon or cadmium telluride, other leading contenders in the photovoltaic realm, but to a whole family of compounds. The perovskite family of solar materials is named for its structural similarity to a mineral called perovskite, which was discovered in 1839 and named after Russian mineralogist L.A. Perovski.

    The original mineral perovskite, which is calcium titanium oxide (CaTiO3), has a distinctive crystal configuration. It has a three-part structure, whose components have come to be labeled A, B and X, in which lattices of the different components are interlaced. The family of perovskites consists of the many possible combinations of elements or molecules that can occupy each of the three components and form a structure similar to that of the original perovskite itself. (Some researchers even bend the rules a little by naming other crystal structures with similar elements “perovskites,” although this is frowned upon by crystallographers.)

    “You can mix and match atoms and molecules into the structure, with some limits. For instance, if you try to stuff a molecule that’s too big into the structure, you’ll distort it. Eventually you might cause the 3D crystal to separate into a 2D layered structure, or lose ordered structure entirely,” says Tonio Buonassisi, professor of mechanical engineering at MIT and director of the Photovoltaics Research Laboratory. “Perovskites are highly tunable, like a build-your-own-adventure type of crystal structure,” he says.

    That structure of interlaced lattices consists of ions or charged molecules, two of them (A and B) positively charged and the other one (X) negatively charged. The A and B ions are typically of quite different sizes, with the A being larger. 

    Within the overall category of perovskites, there are a number of types, including metal oxide perovskites, which have found applications in catalysis and in energy storage and conversion, such as in fuel cells and metal-air batteries. But a main focus of research activity for more than a decade has been on lead halide perovskites, according to Buonassisi says.

    Within that category, there is still a legion of possibilities, and labs around the world are racing through the tedious work of trying to find the variations that show the best performance in efficiency, cost, and durability — which has so far been the most challenging of the three.

    Many teams have also focused on variations that eliminate the use of lead, to avoid its environmental impact. Buonassisi notes, however, that “consistently over time, the lead-based devices continue to improve in their performance, and none of the other compositions got close in terms of electronic performance.” Work continues on exploring alternatives, but for now none can compete with the lead halide versions.

    One of the great advantages perovskites offer is their great tolerance of defects in the structure, he says. Unlike silicon, which requires extremely high purity to function well in electronic devices, perovskites can function well even with numerous imperfections and impurities.

    Searching for promising new candidate compositions for perovskites is a bit like looking for a needle in a haystack, but recently researchers have come up with a machine-learning system that can greatly streamline this process. This new approach could lead to a much faster development of new alternatives, says Buonassisi, who was a co-author of that research.

    While perovskites continue to show great promise, and several companies are already gearing up to begin some commercial production, durability remains the biggest obstacle they face. While silicon solar panels retain up to 90 percent of their power output after 25 years, perovskites degrade much faster. Great progress has been made — initial samples lasted only a few hours, then weeks or months, but newer formulations have usable lifetimes of up to a few years, suitable for some applications where longevity is not essential.

    From a research perspective, Buonassisi says, one advantage of perovskites is that they are relatively easy to make in the lab — the chemical constituents assemble readily. But that’s also their downside: “The material goes together very easily at room temperature,” he says, “but it also comes apart very easily at room temperature. Easy come, easy go!”

    To deal with that issue, most researchers are focused on using various kinds of protective materials to encapsulate the perovskite, protecting it from exposure to air and moisture. But others are studying the exact mechanisms that lead to that degradation, in hopes of finding formulations or treatments that are more inherently robust. A key finding is that a process called autocatalysis is largely to blame for the breakdown.

    In autocatalysis, as soon as one part of the material starts to degrade, its reaction products act as catalysts to start degrading the neighboring parts of the structure, and a runaway reaction gets underway. A similar problem existed in the early research on some other electronic materials, such as organic light-emitting diodes (OLEDs), and was eventually solved by adding additional purification steps to the raw materials, so a similar solution may be found in the case of perovskites, Buonassisi suggests.

    Buonassisi and his co-researchers recently completed a study showing that once perovskites reach a usable lifetime of at least a decade, thanks to their much lower initial cost that would be sufficient to make them economically viable as a substitute for silicon in large, utility-scale solar farms.

    Overall, progress in the development of perovskites has been impressive and encouraging, he says. With just a few years of work, it has already achieved efficiencies comparable to levels that cadmium telluride (CdTe), “which has been around for much longer, is still struggling to achieve,” he says. “The ease with which these higher performances are reached in this new material are almost stupefying.” Comparing the amount of research time spent to achieve a 1 percent improvement in efficiency, he says, the progress on perovskites has been somewhere between 100 and 1000 times faster than that on CdTe. “That’s one of the reasons it’s so exciting,” he says. More

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    Getting the carbon out of India’s heavy industries

    The world’s third largest carbon emitter after China and the United States, India ranks seventh in a major climate risk index. Unless India, along with the nearly 200 other signatory nations of the Paris Agreement, takes aggressive action to keep global warming well below 2 degrees Celsius relative to preindustrial levels, physical and financial losses from floods, droughts, and cyclones could become more severe than they are today. So, too, could health impacts associated with the hazardous air pollution levels now affecting more than 90 percent of its population.  

    To address both climate and air pollution risks and meet its population’s escalating demand for energy, India will need to dramatically decarbonize its energy system in the coming decades. To that end, its initial Paris Agreement climate policy pledge calls for a reduction in carbon dioxide intensity of GDP by 33-35 percent by 2030 from 2005 levels, and an increase in non-fossil-fuel-based power to about 40 percent of cumulative installed capacity in 2030. At the COP26 international climate change conference, India announced more aggressive targets, including the goal of achieving net-zero emissions by 2070.

    Meeting its climate targets will require emissions reductions in every economic sector, including those where emissions are particularly difficult to abate. In such sectors, which involve energy-intensive industrial processes (production of iron and steel; nonferrous metals such as copper, aluminum, and zinc; cement; and chemicals), decarbonization options are limited and more expensive than in other sectors. Whereas replacing coal and natural gas with solar and wind could lower carbon dioxide emissions in electric power generation and transportation, no easy substitutes can be deployed in many heavy industrial processes that release CO2 into the air as a byproduct.

    However, other methods could be used to lower the emissions associated with these processes, which draw upon roughly 50 percent of India’s natural gas, 25 percent of its coal, and 20 percent of its oil. Evaluating the potential effectiveness of such methods in the next 30 years, a new study in the journal Energy Economics led by researchers at the MIT Joint Program on the Science and Policy of Global Change is the first to explicitly explore emissions-reduction pathways for India’s hard-to-abate sectors.

    Using an enhanced version of the MIT Economic Projection and Policy Analysis (EPPA) model, the study assesses existing emissions levels in these sectors and projects how much they can be reduced by 2030 and 2050 under different policy scenarios. Aimed at decarbonizing industrial processes, the scenarios include the use of subsidies to increase electricity use, incentives to replace coal with natural gas, measures to improve industrial resource efficiency, policies to put a price on carbon, carbon capture and storage (CCS) technology, and hydrogen in steel production.

    The researchers find that India’s 2030 Paris Agreement pledge may still drive up fossil fuel use and associated greenhouse gas emissions, with projected carbon dioxide emissions from hard-to-abate sectors rising by about 2.6 times from 2020 to 2050. But scenarios that also promote electrification, natural gas support, and resource efficiency in hard-to-abate sectors can lower their CO2 emissions by 15-20 percent.

    While appearing to move the needle in the right direction, those reductions are ultimately canceled out by increased demand for the products that emerge from these sectors. So what’s the best path forward?

    The researchers conclude that only the incentive of carbon pricing or the advance of disruptive technology can move hard-to-abate sector emissions below their current levels. To achieve significant emissions reductions, they maintain, the price of carbon must be high enough to make CCS economically viable. In that case, reductions of 80 percent below current levels could be achieved by 2050.

    “Absent major support from the government, India will be unable to reduce carbon emissions in its hard-to-abate sectors in alignment with its climate targets,” says MIT Joint Program deputy director Sergey Paltsev, the study’s lead author. “A comprehensive government policy could provide robust incentives for the private sector in India and generate favorable conditions for foreign investments and technology advances. We encourage decision-makers to use our findings to design efficient pathways to reduce emissions in those sectors, and thereby help lower India’s climate and air pollution-related health risks.” More

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    Tapping into the million-year energy source below our feet

    There’s an abandoned coal power plant in upstate New York that most people regard as a useless relic. But MIT’s Paul Woskov sees things differently.

    Woskov, a research engineer in MIT’s Plasma Science and Fusion Center, notes the plant’s power turbine is still intact and the transmission lines still run to the grid. Using an approach he’s been working on for the last 14 years, he’s hoping it will be back online, completely carbon-free, within the decade.

    In fact, Quaise Energy, the company commercializing Woskov’s work, believes if it can retrofit one power plant, the same process will work on virtually every coal and gas power plant in the world.

    Quaise is hoping to accomplish those lofty goals by tapping into the energy source below our feet. The company plans to vaporize enough rock to create the world’s deepest holes and harvest geothermal energy at a scale that could satisfy human energy consumption for millions of years. They haven’t yet solved all the related engineering challenges, but Quaise’s founders have set an ambitious timeline to begin harvesting energy from a pilot well by 2026.

    The plan would be easier to dismiss as unrealistic if it were based on a new and unproven technology. But Quaise’s drilling systems center around a microwave-emitting device called a gyrotron that has been used in research and manufacturing for decades.

    “This will happen quickly once we solve the immediate engineering problems of transmitting a clean beam and having it operate at a high energy density without breakdown,” explains Woskov, who is not formally affiliated with Quaise but serves as an advisor. “It’ll go fast because the underlying technology, gyrotrons, are commercially available. You could place an order with a company and have a system delivered right now — granted, these beam sources have never been used 24/7, but they are engineered to be operational for long time periods. In five or six years, I think we’ll have a plant running if we solve these engineering problems. I’m very optimistic.”

    Woskov and many other researchers have been using gyrotrons to heat material in nuclear fusion experiments for decades. It wasn’t until 2008, however, after the MIT Energy Initiative (MITEI) published a request for proposals on new geothermal drilling technologies, that Woskov thought of using gyrotrons for a new application.

    “[Gyrotrons] haven’t been well-publicized in the general science community, but those of us in fusion research understood they were very powerful beam sources — like lasers, but in a different frequency range,” Woskov says. “I thought, why not direct these high-power beams, instead of into fusion plasma, down into rock and vaporize the hole?”

    As power from other renewable energy sources has exploded in recent decades, geothermal energy has plateaued, mainly because geothermal plants only exist in places where natural conditions allow for energy extraction at relatively shallow depths of up to 400 feet beneath the Earth’s surface. At a certain point, conventional drilling becomes impractical because deeper crust is both hotter and harder, which wears down mechanical drill bits.

    Woskov’s idea to use gyrotron beams to vaporize rock sent him on a research journey that has never really stopped. With some funding from MITEI, he began running tests, quickly filling his office with small rock formations he’d blasted with millimeter waves from a small gyrotron in MIT’s Plasma Science and Fusion Center.

    Woskov displaying samples in his lab in 2016.

    Photo: Paul Rivenberg

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    Around 2018, Woskov’s rocks got the attention of Carlos Araque ’01, SM ’02, who had spent his career in the oil and gas industry and was the technical director of MIT’s investment fund The Engine at the time.

    That year, Araque and Matt Houde, who’d been working with geothermal company AltaRock Energy, founded Quaise. Quaise was soon given a grant by the Department of Energy to scale up Woskov’s experiments using a larger gyrotron.

    With the larger machine, the team hopes to vaporize a hole 10 times the depth of Woskov’s lab experiments. That is expected to be accomplished by the end of this year. After that, the team will vaporize a hole 10 times the depth of the previous one — what Houde calls a 100-to-1 hole.

    “That’s something [the DOE] is particularly interested in, because they want to address the challenges posed by material removal over those greater lengths — in other words, can we show we’re fully flushing out the rock vapors?” Houde explains. “We believe the 100-to-1 test also gives us the confidence to go out and mobilize a prototype gyrotron drilling rig in the field for the first field demonstrations.”

    Tests on the 100-to-1 hole are expected to be completed sometime next year. Quaise is also hoping to begin vaporizing rock in field tests late next year. The short timeline reflects the progress Woskov has already made in his lab.

    Although more engineering research is needed, ultimately, the team expects to be able to drill and operate these geothermal wells safely. “We believe, because of Paul’s work at MIT over the past decade, that most if not all of the core physics questions have been answered and addressed,” Houde says. “It’s really engineering challenges we have to answer, which doesn’t mean they’re easy to solve, but we’re not working against the laws of physics, to which there is no answer. It’s more a matter of overcoming some of the more technical and cost considerations to making this work at a large scale.”

    The company plans to begin harvesting energy from pilot geothermal wells that reach rock temperatures at up to 500 C by 2026. From there, the team hopes to begin repurposing coal and natural gas plants using its system.

    “We believe, if we can drill down to 20 kilometers, we can access these super-hot temperatures in greater than 90 percent of locations across the globe,” Houde says.

    Quaise’s work with the DOE is addressing what it sees as the biggest remaining questions about drilling holes of unprecedented depth and pressure, such as material removal and determining the best casing to keep the hole stable and open. For the latter problem of well stability, Houde believes additional computer modeling is needed and expects to complete that modeling by the end of 2024.

    By drilling the holes at existing power plants, Quaise will be able to move faster than if it had to get permits to build new plants and transmission lines. And by making their millimeter-wave drilling equipment compatible with the existing global fleet of drilling rigs, it will also allow the company to tap into the oil and gas industry’s global workforce.

    “At these high temperatures [we’re accessing], we’re producing steam very close to, if not exceeding, the temperature that today’s coal and gas-fired power plants operate at,” Houde says. “So, we can go to existing power plants and say, ‘We can replace 95 to 100 percent of your coal use by developing a geothermal field and producing steam from the Earth, at the same temperature you’re burning coal to run your turbine, directly replacing carbon emissions.”

    Transforming the world’s energy systems in such a short timeframe is something the founders see as critical to help avoid the most catastrophic global warming scenarios.

    “There have been tremendous gains in renewables over the last decade, but the big picture today is we’re not going nearly fast enough to hit the milestones we need for limiting the worst impacts of climate change,” Houde says. “[Deep geothermal] is a power resource that can scale anywhere and has the ability to tap into a large workforce in the energy industry to readily repackage their skills for a totally carbon free energy source.” More

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    Making hydrogen power a reality

    For decades, government and industry have looked to hydrogen as a potentially game-changing tool in the quest for clean energy. As far back as the early days of the Clinton administration, energy sector observers and public policy experts have extolled the virtues of hydrogen — to the point that some people have joked that hydrogen is the energy of the future, “and always will be.”

    Even as wind and solar power have become commonplace in recent years, hydrogen has been held back by high costs and other challenges. But the fuel may finally be poised to have its moment. At the MIT Energy Initiative Spring Symposium — entitled “Hydrogen’s role in a decarbonized energy system” — experts discussed hydrogen production routes, hydrogen consumption markets, the path to a robust hydrogen infrastructure, and policy changes needed to achieve a “hydrogen future.”

    During one panel, “Options for producing low-carbon hydrogen at scale,” four experts laid out existing and planned efforts to leverage hydrogen for decarbonization. 

    “The race is on”

    Huyen N. Dinh, a senior scientist and group manager at the National Renewable Energy Laboratory (NREL), is the director of HydroGEN, a consortium of several U.S. Department of Energy (DOE) national laboratories that accelerates research and development of innovative and advanced water splitting materials and technologies for clean, sustainable, and low-cost hydrogen production.

    For the past 14 years, Dinh has worked on fuel cells and hydrogen production for NREL. “We think that the 2020s is the decade of hydrogen,” she said. Dinh believes that the energy carrier is poised to come into its own over the next few years, pointing to several domestic and international activities surrounding the fuel and citing a Hydrogen Council report that projected the future impacts of hydrogen — including 30 million jobs and $2.5 trillion in global revenue by 2050.

    “Now is the time for hydrogen, and the global race is on,” she said.

    Dinh also explained the parameters of the Hydrogen Shot — the first of the DOE’s “Energy Earthshots” aimed at accelerating breakthroughs for affordable and reliable clean energy solutions. Hydrogen fuel currently costs around $5 per kilogram to produce, and the Hydrogen Shot’s stated goal is to bring that down by 80 percent to $1 per kilogram within a decade.

    The Hydrogen Shot will be facilitated by $9.5 billion in funding for at least four clean hydrogen hubs located in different parts of the United States, as well as extensive research and development, manufacturing, and recycling from last year’s bipartisan infrastructure law. Still, Dinh noted that it took more than 40 years for solar and wind power to become cost competitive, and now industry, government, national lab, and academic leaders are hoping to achieve similar reductions in hydrogen fuel costs over a much shorter time frame. In the near term, she said, stakeholders will need to improve the efficiency, durability, and affordability of hydrogen production through electrolysis (using electricity to split water) using today’s renewable and nuclear power sources. Over the long term, the focus may shift to splitting water more directly through heat or solar energy, she said.

    “The time frame is short, the competition is intense, and a coordinated effort is critical for domestic competitiveness,” Dinh said.

    Hydrogen across continents

    Wambui Mutoru, principal engineer for international commercial development, exploration, and production international at the Norwegian global energy company Equinor, said that hydrogen is an important component in the company’s ambitions to be carbon-neutral by 2050. The company, in collaboration with partners, has several hydrogen projects in the works, and Mutoru laid out the company’s Hydrogen to Humber project in Northern England. Currently, the Humber region emits more carbon dioxide than any other industrial cluster in the United Kingdom — 50 percent more, in fact, than the next-largest carbon emitter.   

    “The ambition here is for us to deploy the world’s first at-scale hydrogen value chain to decarbonize the Humber industrial cluster,” Mutoru said.

    The project consists of three components: a clean hydrogen production facility, an onshore hydrogen and carbon dioxide transmission network, and offshore carbon dioxide transportation and storage operations. Mutoru highlighted the importance of carbon capture and storage in hydrogen production. Equinor, she said, has captured and sequestered carbon offshore for more than 25 years, storing more than 25 million tons of carbon dioxide during that time.

    Mutoru also touched on Equinor’s efforts to build a decarbonized energy hub in the Appalachian region of the United States, covering territory in Ohio, West Virginia, and Pennsylvania. By 2040, she said, the company’s ambition is to produce about 1.5 million tons of clean hydrogen per year in the region — roughly equivalent to 6.8 gigawatts of electricity — while also storing 30 million tons of carbon dioxide.

    Mutoru acknowledged that the biggest challenge facing potential hydrogen producers is the current lack of viable business models. “Resolving that challenge requires cross-industry collaboration, and supportive policy frameworks so that the market for hydrogen can be built and sustained over the long term,” she said.

    Confronting barriers

    Gretchen Baier, executive external strategy and communications leader for Dow, noted that the company already produces hydrogen in multiple ways. For one, Dow operates the world’s largest ethane cracker, in Texas. An ethane cracker heats ethane to break apart molecular bonds to form ethylene, with hydrogen one of the byproducts of the process. Also, Baier showed a slide of the 1891 patent for the electrolysis of brine water, which also produces hydrogen. The company still engages in this practice, but Dow does not have an effective way of utilizing the resulting hydrogen for their own fuel.

    “Just take a moment to think about that,” Baier said. “We’ve been talking about hydrogen production and the cost of it, and this is basically free hydrogen. And it’s still too much of a barrier to somewhat recycle that and use it for ourselves. The environment is clearly changing, and we do have plans for that, but I think that kind of sets some of the challenges that face industry here.”

    However, Baier said, hydrogen is expected to play a significant role in Dow’s future as the company attempts to decarbonize by 2050. The company, she said, plans to optimize hydrogen allocation and production, retrofit turbines for hydrogen fueling, and purchase clean hydrogen. By 2040, Dow expects more than 60 percent of its sites to be hydrogen-ready.

    Baier noted that hydrogen fuel is not a “panacea,” but rather one among many potential contributors as industry attempts to reduce or eliminate carbon emissions in the coming decades. “Hydrogen has an important role, but it’s not the only answer,” she said.

    “This is real”

    Colleen Wright is vice president of corporate strategy for Constellation, which recently separated from Exelon Corporation. (Exelon now owns the former company’s regulated utilities, such as Commonwealth Edison and Baltimore Gas and Electric, while Constellation owns the competitive generation and supply portions of the business.) Wright stressed the advantages of nuclear power in hydrogen production, which she said include superior economics, low barriers to implementation, and scalability.

    “A quarter of emissions in the world are currently from hard-to-decarbonize sectors — the industrial sector, steel making, heavy-duty transportation, aviation,” she said. “These are really challenging decarbonization sectors, and as we continue to expand and electrify, we’re going to need more supply. We’re also going to need to produce clean hydrogen using emissions-free power.”

    “The scale of nuclear power plants is uniquely suited to be able to scale hydrogen production,” Wright added. She mentioned Constellation’s Nine Mile Point site in the State of New York, which received a DOE grant for a pilot program that will see a proton exchange membrane electrolyzer installed at the site.

    “We’re very excited to see hydrogen go from a [research and development] conversation to a commercial conversation,” she said. “We’ve been calling it a little bit of a ‘middle-school dance.’ Everybody is standing around the circle, waiting to see who’s willing to put something at stake. But this is real. We’re not dancing around the edges. There are a lot of people who are big players, who are willing to put skin in the game today.” More

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    Donald Sadoway wins European Inventor Award for liquid metal batteries

    MIT Professor Donald Sadoway has won the 2022 European Inventor Award, in the category for Non-European Patent Office Countries, for his work on liquid metal batteries that could enable the long-term storage of renewable energy.

    Sadoway is the John F. Elliott Professor of Materials Chemistry in MIT’s Department of Materials Science and Engineering, and a longtime supporter and friend of the Materials Research Laboratory.

    “By enabling the large-scale storage of renewable energy, Donald Sadoway’s invention is a huge step towards the deployment of carbon-free electricity generation,” says António Campinos, president of the European Patent Office. “He has spent his career studying electrochemistry and has transformed this expertise into an invention that represents a huge step forward in the transition to green energy.”

    Sadoway was honored at the 2022 European Inventor Award ceremony on June 21. The award is one of Europe’s most prestigious innovation prizes and is presented annually to outstanding inventors from Europe and beyond who have made an exceptional contribution to society, technological progress, and economic growth.

    When accepting the award in Munich, Sadoway told the audience:

    “I am astonished. When I look at all the patented technologies that are represented at this event I see an abundance of excellence, all of them solutions to pressing problems. I wonder if the judges are assessing not only degrees of excellence but degrees of urgency. The liquid metal battery addresses an existential threat to the health of our atmosphere which is related to climate change.

    “By hosting this event the EPO celebrates invention. The thread that connects all the inventors is their efforts to make the world a better place. In my judgment there is no nobler pursuit. So perhaps this is a celebration of nobility.”

    Sadoway’s liquid metal batteries consist of three liquid layers of different densities, which naturally separate in the same way as oil and vinegar do in a salad dressing. The top and bottom layers are made from molten metals, with a middle layer of molten liquid salt.

    To keep the metals liquid, the batteries need to operate at extremely high temperatures, so Sadoway designed a system that is self-heating and insulated, requiring no external heating or cooling. They have a lifespan of more than 20 years, can maintain 99 percent of their capacity over 5,000 charging cycles, and have no combustible materials, meaning there is no fire risk.

    In 2010, with a patent for his invention and support from Bill Gates, Sadoway co-founded Ambri, based in Marlborough, Massachusetts just outside Boston, to develop a commercial product. The company will soon install a unit on a 3,700-acre development for a data center in Nevada. This battery will store energy from a reported 500 megawatts of on-site renewable generation, the same output as a natural gas power plant.

    Born in 1950 into a family of Ukrainian immigrants in Canada, Sadoway studied chemical metallurgy specializing in what he calls “extreme electrochemistry” — chemical reactions in molten salts and liquid metals that have been heated to over 500 degrees Celsius. After earning his BASc, MASc, and PhD, all from the University of Toronto, he joined the faculty at MIT in 1978. More

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    Evan Leppink: Seeking a way to better stabilize the fusion environment

    “Fusion energy was always one of those kind-of sci-fi technologies that you read about,” says nuclear science and engineering PhD candidate Evan Leppink. He’s recalling the time before fusion became a part of his daily hands-on experience at MIT’s Plasma Science and Fusion Center, where he is studying a unique way to drive current in a tokamak plasma using radiofrequency (RF) waves. 

    Now, an award from the U.S. Department of Energy’s (DOE) Office of Science Graduate Student Research (SCGSR) Program will support his work with a 12-month residency at the DIII-D National Fusion Facility in San Diego, California.

    Like all tokamaks, DIII-D generates hot plasma inside a doughnut-shaped vacuum chamber wrapped with magnets. Because plasma will follow magnetic field lines, tokamaks are able to contain the turbulent plasma fuel as it gets hotter and denser, keeping it away from the edges of the chamber where it could damage the wall materials. A key part of the tokamak concept is that part of the magnetic field is created by electrical currents in the plasma itself, which helps to confine and stabilize the configuration. Researchers often launch high-power RF waves into tokamaks to drive that current.

    Leppink will be contributing to research, led by his MIT advisor Steve Wukitch, that pursues launching RF waves in DIII-D using a unique compact antenna placed on the tokamak center column. Typically, antennas are placed inside the tokamak on the outer edge of the doughnut, farthest from the central hole (or column), primarily because access and installation are easier there. This is known as the “low-field side,” because the magnetic field is lower there than at the central column, the “high-field side.” This MIT-led experiment, for the first time, will mount an antenna on the high-field side. There is some theoretical evidence that placing the wave launcher there could improve power penetration and current drive efficiency. And because the plasma environment is less harsh on this side, the antenna will survive longer, a factor important for any future power-producing tokamak.

    Leppink’s work on DIII-D focuses specifically on measuring the density of plasmas generated in the tokamak, for which he developed a “reflectometer.” This small antenna launches microwaves into the plasma, which reflect back to the antenna to be measured. The time that it takes for these microwaves to traverse the plasma provides information about the plasma density, allowing researchers to build up detailed density profiles, data critical for injecting RF power into the plasma.

    “Research shows that when we try to inject these waves into the plasma to drive the current, they can lose power as they travel through the edge region of the tokamak, and can even have problems entering the core of the plasma, where we would most like to direct them,” says Leppink. “My diagnostic will measure that edge region on the high-field side near the launcher in great detail, which provides us a way to directly verify calculations or compare actual results with simulation results.”

    Although focused on his own research, Leppink has excelled at priming other students for success in their studies and research. In 2021 he received the NSE Outstanding Teaching Assistant and Mentorship Award.

    “The highlights of TA’ing for me were the times when I could watch students go from struggling with a difficult topic to fully understanding it, often with just a nudge in the right direction and then allowing them to follow their own intuition the rest of the way,” he says.

    The right direction for Leppink points toward San Diego and RF current drive experiments on DIII-D. He is grateful for the support from the SCGSR, a program created to prepare graduate students like him for science, technology, engineering, or mathematics careers important to the DOE Office of Science mission. It provides graduate thesis research opportunities through extended residency at DOE national laboratories. He has already made several trips to DIII-D, in part to install his reflectometer, and has been impressed with the size of the operation.

    “It takes a little while to kind of compartmentalize everything and say, ‘OK, well, here’s my part of the machine. This is what I’m doing.’ It can definitely be overwhelming at times. But I’m blessed to be able to work on what has been the workhorse tokamak of the United States for the past few decades.” More

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    Helping renewable energy projects succeed in local communities

    Jungwoo Chun makes surprising discoveries about sustainability initiatives by zooming in on local communities.

    His discoveries lie in understanding how renewable energy infrastructure develops at a local level. With so many stakeholders in a community — citizens, government officials, businesses, and other organizations — the development process gets complicated very quickly. Chun works to unpack stakeholder relationships to help local renewable energy projects move forward.

    While his interests today are in local communities around the U.S., Chun comes from a global background. Growing up, his family moved frequently due to his dad’s work. He lived in Seoul, South Korea until elementary school and then hopped from city to city around Asia, spending time in China, Hong Kong, and Singapore. When it was time for college, he returned to South Korea, majoring in international studies at Korea University and later completing his master’s there in the same field.

    After graduating, Chun wanted to leverage his international expertise to tackle climate change. So, he pursued a second master’s in international environmental policy with William Moomaw at Tufts University.

    During that time, Chun came across an article on climate change by David Victor, a professor in public policy at the University of California at San Diego. Victor argued that while international efforts to fight climate change are necessary, more tangible progress can be made through local efforts catered to each country. That prompted Chun to think a step further: “What can we do in the local community to make a little bit of a difference, which could add up to something big in the long term?”

    With a renewed direction for his goals, Chun arrived at the MIT Department of Urban Studies and Planning, specializing in environmental policy and planning. But he was still missing that final inspirational spark to proactively pursue his goals — until he began working with his primary advisor, Lawrence Susskind, the Ford Professor of Urban and Environmental Planning and director of the Science Impact Collaborative.

    For previous research projects, “I would just do what I was told,” Chun says, but his new advisor “really opened [his] eyes” to being an active member of the community. From the start, Susskind has encouraged Chun to share his research ideas and has shown him how to leverage his research skills for public service. Over the past few years, Chun has also taught several classes with Susskind, learning to approach education thoughtfully for an engaging and equitable classroom. Because of their relationship, Chun now always searches for ways to make a difference through research, teaching, and public service.

    Understanding renewable energy projects at a local level

    For his main dissertation project with Susskind, Chun is studying community-owned solar energy projects, working to understand what makes them successful.

    Often, communities don’t have the required expertise to carry out these projects on their own and instead look to advisory organizations for help. But little research has been done on these organizations and the roles that they play in developing solar energy infrastructure.

    Through over 200 surveys and counting, Chun has discovered that these organizations act as life-long collaborators to communities and are critical in getting community-owned solar projects up and running. At the start of these projects, they walk communities through a mountain of logistics for setting up solar energy infrastructure, including permit applications, budgeting, and contractor employment. After the infrastructure is in place, the organizations stay involved, serving as consultants when needed and sometimes even becoming partners.

    Because of these roles, Chun calls these organizations “intermediaries,” drawing a parallel with roles in in conflict resolution. “But it’s much more than that,” he adds. Intermediaries help local communities “build a movement [for community-owned solar energy projects] … and empower them to be independent and self-sustaining.”

    Chun is also working on another project with Susskind, looking at situations where communities are opposed to renewable energy infrastructure. For this project, Chun is supervising and mentoring a group of five undergraduates. Together, they are trying to pinpoint the reasons behind local opposition to renewable energy projects.

    The idea for this project emerged two years ago, when Chun heard in the news that many solar and wind projects were being delayed or cancelled due to local opposition. But the reasons for this opposition weren’t thoroughly researched.

    “When we started to dig a little deeper, [we found that] communities oppose these projects even though they aren’t opposed to renewable energy,” Chun says. The primary reasons for opposition lie in land use concerns, including financial challenges, health and safety concerns, and ironically, environmental consequences. By better understanding these concerns, Chun hopes to help more renewable energy projects succeed and bring society closer to a sustainable future.

    Bringing research to the classroom and community

    Right now, Chun is looking to bring his research insights on renewable energy infrastructure into the classroom. He’s developing a course on renewable energy that will act as a “clinic” where students will work with communities to understand their concerns for potential renewable energy projects. The students’ findings will then be passed onto project leaders to help them address these concerns.

    This new course is modeled after 11.074/11.274 (Cybersecurity Clinic), which Chun has helped develop over the past few years. In this clinic, students work with local governments in New England to assess potential cybersecurity vulnerabilities in their digital systems. At first, “a lot of city governments were very skeptical, like ‘students doing service for us…?’” Chun says. “But in the end, they were all very satisfied with the outcome” and found the assessments “impactful.”

    Since the Cybersecurity Clinic has kicked off, other universities have approached Chun and his co-instructors about developing their own regional clinics. Now, there are cybersecurity clinics operating around the world. “That’s been a huge success,” Chun says. Going forward, “we’d like to expand the benefit of this clinic [to address] communities opposing renewable energy [projects].” The new course will be a philosophical trifecta for Chun, combining his commitments to research, teaching, and public service.

    Chun plans to wrap up his PhD at the end of this summer and is currently writing his dissertation on community-owned solar energy projects. “I’m done with all the background work — working the soil and throwing the seeds in the right place,” he says, “It’s now time to gather all the crops and present the work.” More

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    MIT Climate and Sustainability Consortium announces recipients of inaugural MCSC Seed Awards

    The MIT Climate and Sustainability Consortium (MCSC) has awarded 20 projects a total of $5 million over two years in its first-ever 2022 MCSC Seed Awards program. The winning projects are led by principal investigators across all five of MIT’s schools.

    The goal of the MCSC Seed Awards is to engage MIT researchers and link the economy-wide work of the consortium to ongoing and emerging climate and sustainability efforts across campus. The program offers further opportunity to build networks among the awarded projects to deepen the impact of each and ensure the total is greater than the sum of its parts.

    For example, to drive progress under the awards category Circularity and Materials, the MCSC can facilitate connections between the technologists at MIT who are developing recovery approaches for metals, plastics, and fiber; the urban planners who are uncovering barriers to reuse; and the engineers, who will look for efficiency opportunities in reverse supply chains.

    “The MCSC Seed Awards are designed to complement actions previously outlined in Fast Forward: MIT’s Climate Action Plan for the Decade and, more specifically, the Climate Grand Challenges,” says Anantha P. Chandrakasan, dean of the MIT School of Engineering, Vannevar Bush Professor of Electrical Engineering and Computer Science, and chair of the MIT Climate and Sustainability Consortium. “In collaboration with seed award recipients and MCSC industry members, we are eager to engage in interdisciplinary exploration and propel urgent advancements in climate and sustainability.” 

    By supporting MIT researchers with expertise in economics, infrastructure, community risk assessment, mobility, and alternative fuels, the MCSC will accelerate implementation of cross-disciplinary solutions in the awards category Decarbonized and Resilient Value Chains. Enhancing Natural Carbon Sinks and building connections to local communities will require associations across experts in ecosystem change, biodiversity, improved agricultural practice and engagement with farmers, all of which the consortium can begin to foster through the seed awards.

    “Funding opportunities across campus has been a top priority since launching the MCSC,” says Jeremy Gregory, MCSC executive director. “It is our honor to support innovative teams of MIT researchers through the inaugural 2022 MCSC Seed Awards program.”

    The winning projects are tightly aligned with the MCSC’s areas of focus, which were derived from a year of highly engaged collaborations with MCSC member companies. The projects apply across the member’s climate and sustainability goals.

    The MCSC’s 16 member companies span many industries, and since early 2021, have met with members of the MIT community to define focused problem statements for industry-specific challenges, identify meaningful partnerships and collaborations, and develop clear and scalable priorities. Outcomes from these collaborations laid the foundation for the focus areas, which have shaped the work of the MCSC. Specifically, the MCSC Industry Advisory Board engaged with MIT on key strategic directions, and played a critical role in the MCSC’s series of interactive events. These included virtual workshops hosted last summer, each on a specific topic that allowed companies to work with MIT and each other to align key assumptions, identify blind spots in corporate goal-setting, and leverage synergies between members, across industries. The work continued in follow-up sessions and an annual symposium.

    “We are excited to see how the seed award efforts will help our member companies reach or even exceed their ambitious climate targets, find new cross-sector links among each other, seek opportunities to lead, and ripple key lessons within their industry, while also deepening the Institute’s strong foundation in climate and sustainability research,” says Elsa Olivetti, the Esther and Harold E. Edgerton Associate Professor in Materials Science and Engineering and MCSC co-director.

    As the seed projects take shape, the MCSC will provide ongoing opportunities for awardees to engage with the Industry Advisory Board and technical teams from the MCSC member companies to learn more about the potential for linking efforts to support and accelerate their climate and sustainability goals. Awardees will also have the chance to engage with other members of the MCSC community, including its interdisciplinary Faculty Steering Committee.

    “One of our mantras in the MCSC is to ‘amplify and extend’ existing efforts across campus; we’re always looking for ways to connect the collaborative industry relationships we’re building and the work we’re doing with other efforts on campus,” notes Jeffrey Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems, head of the Department of Materials Science and Engineering, and MCSC co-director. “We feel the urgency as well as the potential, and we don’t want to miss opportunities to do more and go faster.”

    The MCSC Seed Awards complement the Climate Grand Challenges, a new initiative to mobilize the entire MIT research community around developing the bold, interdisciplinary solutions needed to address difficult, unsolved climate problems. The 27 finalist teams addressed four broad research themes, which align with the MCSC’s focus areas. From these finalist teams, five flagship projects were announced in April 2022.

    The parallels between MCSC’s focus areas and the Climate Grand Challenges themes underscore an important connection between the shared long-term research interests of industry and academia. The challenges that some of the world’s largest and most influential companies have identified are complementary to MIT’s ongoing research and innovation — highlighting the tremendous opportunity to develop breakthroughs and scalable solutions quickly and effectively. Special Presidential Envoy for Climate John Kerry underscored the importance of developing these scalable solutions, including critical new technology, during a conversation with MIT President L. Rafael Reif at MIT’s first Climate Grand Challenges showcase event last month.

    Both the MCSC Seed Awards and the Climate Grand Challenges are part of MIT’s larger commitment and initiative to combat climate change; this was underscored in “Fast Forward: MIT’s Climate Action Plan for the Decade,” which the Institute published in May 2021.

    The project titles and research leads for each of the 20 awardees listed below are categorized by MCSC focus area.

    Decarbonized and resilient value chains

    “Collaborative community mapping toolkit for resilience planning,” led by Miho Mazereeuw, associate professor of architecture and urbanism in the Department of Architecture and director of the Urban Risk Lab (a research lead on Climate Grand Challenges flagship project) and Nicholas de Monchaux, professor and department head in the Department of Architecture
    “CP4All: Fast and local climate projections with scientific machine learning — towards accessibility for all of humanity,” led by Chris Hill, principal research scientist in the Department of Earth, Atmospheric and Planetary Sciences and Dava Newman, director of the MIT Media Lab and the Apollo Program Professor in the Department of Aeronautics and Astronautics
    “Emissions reductions and productivity in U.S. manufacturing,” led by Mert Demirer, assistant professor of applied economics at the MIT Sloan School of Management and Jing Li, assistant professor and William Barton Rogers Career Development Chair of Energy Economics in the MIT Sloan School of Management
    “Logistics electrification through scalable and inter-operable charging infrastructure: operations, planning, and policy,” led by Alex Jacquillat, the 1942 Career Development Professor and assistant professor of operations research and statistics in the MIT Sloan School of Management
    “Powertrain and system design for LOHC-powered long-haul trucking,” led by William Green, the Hoyt Hottel Professor in Chemical Engineering in the Department of Chemical Engineering and postdoctoral officer, and Wai K. Cheng, professor in the Department of Mechanical Engineering and director of the Sloan Automotive Laboratory
    “Sustainable Separation and Purification of Biochemicals and Biofuels using Membranes,” led by John Lienhard, the Abdul Latif Jameel Professor of Water in the Department of Mechanical Engineering, director of the Abdul Latif Jameel Water and Food Systems Lab, and director of the Rohsenow Kendall Heat Transfer Laboratory; and Nicolas Hadjiconstantinou, professor in the Department of Mechanical Engineering, co-director of the Center for Computational Science and Engineering, associate director of the Center for Exascale Simulation of Materials in Extreme Environments, and graduate officer
    “Toolkit for assessing the vulnerability of industry infrastructure siting to climate change,” led by Michael Howland, assistant professor in the Department of Civil and Environmental Engineering

    Circularity and Materials

    “Colorimetric Sulfidation for Aluminum Recycling,” led by Antoine Allanore, associate professor of metallurgy in the Department of Materials Science and Engineering
    “Double Loop Circularity in Materials Design Demonstrated on Polyurethanes,” led by Brad Olsen, the Alexander and I. Michael Kasser (1960) Professor and graduate admissions co-chair in the Department of Chemical Engineering, and Kristala Prather, the Arthur Dehon Little Professor and department executive officer in the Department of Chemical Engineering
    “Engineering of a microbial consortium to degrade and valorize plastic waste,” led by Otto Cordero, associate professor in the Department of Civil and Environmental Engineering, and Desiree Plata, the Gilbert W. Winslow (1937) Career Development Professor in Civil Engineering and associate professor in the Department of Civil and Environmental Engineering
    “Fruit-peel-inspired, biodegradable packaging platform with multifunctional barrier properties,” led by Kripa Varanasi, professor in the Department of Mechanical Engineering
    “High Throughput Screening of Sustainable Polyesters for Fibers,” led by Gregory Rutledge, the Lammot du Pont Professor in the Department of Chemical Engineering, and Brad Olsen, Alexander and I. Michael Kasser (1960) Professor and graduate admissions co-chair in the Department of Chemical Engineering
    “Short-term and long-term efficiency gains in reverse supply chains,” led by Yossi Sheffi, the Elisha Gray II Professor of Engineering Systems, professor in the Department of Civil and Environmental Engineering, and director of the Center for Transportation and Logistics
    The costs and benefits of circularity in building construction, led by Siqi Zheng, the STL Champion Professor of Urban and Real Estate Sustainability at the MIT Center for Real Estate and Department of Urban Studies and Planning, faculty director of the MIT Center for Real Estate, and faculty director for the MIT Sustainable Urbanization Lab; and Randolph Kirchain, principal research scientist and co-director of MIT Concrete Sustainability Hub

    Natural carbon sinks

    “Carbon sequestration through sustainable practices by smallholder farmers,” led by Joann de Zegher, the Maurice F. Strong Career Development Professor and assistant professor of operations management in the MIT Sloan School of Management, and Karen Zheng the George M. Bunker Professor and associate professor of operations management in the MIT Sloan School of Management
    “Coatings to protect and enhance diverse microbes for improved soil health and crop yields,” led by Ariel Furst, the Raymond A. (1921) And Helen E. St. Laurent Career Development Professor of Chemical Engineering in the Department of Chemical Engineering, and Mary Gehring, associate professor of biology in the Department of Biology, core member of the Whitehead Institute for Biomedical Research, and graduate officer
    “ECO-LENS: Mainstreaming biodiversity data through AI,” led by John Fernández, professor of building technology in the Department of Architecture and director of MIT Environmental Solutions Initiative
    “Growing season length, productivity, and carbon balance of global ecosystems under climate change,” led by Charles Harvey, professor in the Department of Civil and Environmental Engineering, and César Terrer, assistant professor in the Department of Civil and Environmental Engineering

    Social dimensions and adaptation

    “Anthro-engineering decarbonization at the million-person scale,” led by Manduhai Buyandelger, professor in the Anthropology Section, and Michael Short, the Class of ’42 Associate Professor of Nuclear Science and Engineering in the Department of Nuclear Science and Engineering
    “Sustainable solutions for climate change adaptation: weaving traditional ecological knowledge and STEAM,” led by Janelle Knox-Hayes, the Lister Brothers Associate Professor of Economic Geography and Planning and head of the Environmental Policy and Planning Group in the Department of Urban Studies and Planning, and Miho Mazereeuw, associate professor of architecture and urbanism in the Department of Architecture and director of the Urban Risk Lab (a research lead on a Climate Grand Challenges flagship project) More