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    Extracting hydrogen from rocks

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    It’s commonly thought that the most abundant element in the universe, hydrogen, exists mainly alongside other elements — with oxygen in water, for example, and with carbon in methane. But naturally occurring underground pockets of pure hydrogen are punching holes in that notion — and generating attention as a potentially unlimited source of carbon-free power. One interested party is the U.S. Department of Energy, which last month awarded $20 million in research grants to 18 teams from laboratories, universities, and private companies to develop technologies that can lead to cheap, clean fuel from the subsurface. Geologic hydrogen, as it’s known, is produced when water reacts with iron-rich rocks, causing the iron to oxidize. One of the grant recipients, MIT Assistant Professor Iwnetim Abate’s research group, will use its $1.3 million grant to determine the ideal conditions for producing hydrogen underground — considering factors such as catalysts to initiate the chemical reaction, temperature, pressure, and pH levels. The goal is to improve efficiency for large-scale production, meeting global energy needs at a competitive cost. The U.S. Geological Survey estimates there are potentially billions of tons of geologic hydrogen buried in the Earth’s crust. Accumulations have been discovered worldwide, and a slew of startups are searching for extractable deposits. Abate is looking to jump-start the natural hydrogen production process, implementing “proactive” approaches that involve stimulating production and harvesting the gas.                                                                                                                         “We aim to optimize the reaction parameters to make the reaction faster and produce hydrogen in an economically feasible manner,” says Abate, the Chipman Development Professor in the Department of Materials Science and Engineering (DMSE). Abate’s research centers on designing materials and technologies for the renewable energy transition, including next-generation batteries and novel chemical methods for energy storage. 

    Sparking innovation

    Interest in geologic hydrogen is growing at a time when governments worldwide are seeking carbon-free energy alternatives to oil and gas. In December, French President Emmanuel Macron said his government would provide funding to explore natural hydrogen. And in February, government and private sector witnesses briefed U.S. lawmakers on opportunities to extract hydrogen from the ground. Today commercial hydrogen is manufactured at $2 a kilogram, mostly for fertilizer and chemical and steel production, but most methods involve burning fossil fuels, which release Earth-heating carbon. “Green hydrogen,” produced with renewable energy, is promising, but at $7 per kilogram, it’s expensive. “If you get hydrogen at a dollar a kilo, it’s competitive with natural gas on an energy-price basis,” says Douglas Wicks, a program director at Advanced Research Projects Agency – Energy (ARPA-E), the Department of Energy organization leading the geologic hydrogen grant program. Recipients of the ARPA-E grants include Colorado School of Mines, Texas Tech University, and Los Alamos National Laboratory, plus private companies including Koloma, a hydrogen production startup that has received funding from Amazon and Bill Gates. The projects themselves are diverse, ranging from applying industrial oil and gas methods for hydrogen production and extraction to developing models to understand hydrogen formation in rocks. The purpose: to address questions in what Wicks calls a “total white space.” “In geologic hydrogen, we don’t know how we can accelerate the production of it, because it’s a chemical reaction, nor do we really understand how to engineer the subsurface so that we can safely extract it,” Wicks says. “We’re trying to bring in the best skills of each of the different groups to work on this under the idea that the ensemble should be able to give us good answers in a fairly rapid timeframe.” Geochemist Viacheslav Zgonnik, one of the foremost experts in the natural hydrogen field, agrees that the list of unknowns is long, as is the road to the first commercial projects. But he says efforts to stimulate hydrogen production — to harness the natural reaction between water and rock — present “tremendous potential.” “The idea is to find ways we can accelerate that reaction and control it so we can produce hydrogen on demand in specific places,” says Zgonnik, CEO and founder of Natural Hydrogen Energy, a Denver-based startup that has mineral leases for exploratory drilling in the United States. “If we can achieve that goal, it means that we can potentially replace fossil fuels with stimulated hydrogen.”

    “A full-circle moment”

    For Abate, the connection to the project is personal. As a child in his hometown in Ethiopia, power outages were a usual occurrence — the lights would be out three, maybe four days a week. Flickering candles or pollutant-emitting kerosene lamps were often the only source of light for doing homework at night. “And for the household, we had to use wood and charcoal for chores such as cooking,” says Abate. “That was my story all the way until the end of high school and before I came to the U.S. for college.” In 1987, well-diggers drilling for water in Mali in Western Africa uncovered a natural hydrogen deposit, causing an explosion. Decades later, Malian entrepreneur Aliou Diallo and his Canadian oil and gas company tapped the well and used an engine to burn hydrogen and power electricity in the nearby village. Ditching oil and gas, Diallo launched Hydroma, the world’s first hydrogen exploration enterprise. The company is drilling wells near the original site that have yielded high concentrations of the gas. “So, what used to be known as an energy-poor continent now is generating hope for the future of the world,” Abate says. “Learning about that was a full-circle moment for me. Of course, the problem is global; the solution is global. But then the connection with my personal journey, plus the solution coming from my home continent, makes me personally connected to the problem and to the solution.”

    Experiments that scale

    Abate and researchers in his lab are formulating a recipe for a fluid that will induce the chemical reaction that triggers hydrogen production in rocks. The main ingredient is water, and the team is testing “simple” materials for catalysts that will speed up the reaction and in turn increase the amount of hydrogen produced, says postdoc Yifan Gao. “Some catalysts are very costly and hard to produce, requiring complex production or preparation,” Gao says. “A catalyst that’s inexpensive and abundant will allow us to enhance the production rate — that way, we produce it at an economically feasible rate, but also with an economically feasible yield.” The iron-rich rocks in which the chemical reaction happens can be found across the United States and the world. To optimize the reaction across a diversity of geological compositions and environments, Abate and Gao are developing what they call a high-throughput system, consisting of artificial intelligence software and robotics, to test different catalyst mixtures and simulate what would happen when applied to rocks from various regions, with different external conditions like temperature and pressure. “And from that we measure how much hydrogen we are producing for each possible combination,” Abate says. “Then the AI will learn from the experiments and suggest to us, ‘Based on what I’ve learned and based on the literature, I suggest you test this composition of catalyst material for this rock.’” The team is writing a paper on its project and aims to publish its findings in the coming months. The next milestones for the project, after developing the catalyst recipe, is designing a reactor that will serve two purposes. First, fitted with technologies such as Raman spectroscopy, it will allow researchers to identify and optimize the chemical conditions that lead to improved rates and yield of hydrogen production. The lab-scale device will also inform the design of a real-world reactor that can accelerate hydrogen production in the field. “That would be a plant-scale reactor that would be implanted into the subsurface,” Abate says. The cross-disciplinary project is also tapping the expertise of Yang Shao-Horn, of MIT’s Department of Mechanical Engineering and DMSE, for computational analysis of the catalyst, and Esteban Gazel, a Cornell University scientist who will lend his expertise in geology and geochemistry. He’ll focus on understanding the iron-rich ultramafic rock formations across the United States and the globe and how they react with water. For Wicks at ARPA-E, the questions Abate and the other grant recipients are asking are just the first, critical steps in uncharted energy territory. “If we can understand how to stimulate these rocks into generating hydrogen, safely getting it up, it really unleashes the potential energy source,” he says. Then the emerging industry will look to oil and gas for the drilling, piping, and gas extraction know-how. “As I like to say, this is enabling technology that we hope to, in a very short term, enable us to say, ‘Is there really something there?’” More

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      With just a little electricity, MIT researchers boost common catalytic reactions

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      A simple technique that uses small amounts of energy could boost the efficiency of some key chemical processing reactions, by up to a factor of 100,000, MIT researchers report. These reactions are at the heart of petrochemical processing, pharmaceutical manufacturing, and many other industrial chemical processes.

      The surprising findings are reported today in the journal Science, in a paper by MIT graduate student Karl Westendorff, professors Yogesh Surendranath and Yuriy Roman-Leshkov, and two others.

      “The results are really striking,” says Surendranath, a professor of chemistry and chemical engineering. Rate increases of that magnitude have been seen before but in a different class of catalytic reactions known as redox half-reactions, which involve the gain or loss of an electron. The dramatically increased rates reported in the new study “have never been observed for reactions that don’t involve oxidation or reduction,” he says.

      The non-redox chemical reactions studied by the MIT team are catalyzed by acids. “If you’re a first-year chemistry student, probably the first type of catalyst you learn about is an acid catalyst,” Surendranath says. There are many hundreds of such acid-catalyzed reactions, “and they’re super important in everything from processing petrochemical feedstocks to making commodity chemicals to doing transformations in pharmaceutical products. The list goes on and on.”

      “These reactions are key to making many products we use daily,” adds Roman-Leshkov, a professor of chemical engineering and chemistry.

      But the people who study redox half-reactions, also known as electrochemical reactions, are part of an entirely different research community than those studying non-redox chemical reactions, known as thermochemical reactions. As a result, even though the technique used in the new study, which involves applying a small external voltage, was well-known in the electrochemical research community, it had not been systematically applied to acid-catalyzed thermochemical reactions.

      People working on thermochemical catalysis, Surendranath says, “usually don’t consider” the role of the electrochemical potential at the catalyst surface, “and they often don’t have good ways of measuring it. And what this study tells us is that relatively small changes, on the order of a few hundred millivolts, can have huge impacts — orders of magnitude changes in the rates of catalyzed reactions at those surfaces.”

      “This overlooked parameter of surface potential is something we should pay a lot of attention to because it can have a really, really outsized effect,” he says. “It changes the paradigm of how we think about catalysis.”

      Chemists traditionally think about surface catalysis based on the chemical binding energy of molecules to active sites on the surface, which influences the amount of energy needed for the reaction, he says. But the new findings show that the electrostatic environment is “equally important in defining the rate of the reaction.”

      The team has already filed a provisional patent application on parts of the process and is working on ways to apply the findings to specific chemical processes. Westendorff says their findings suggest that “we should design and develop different types of reactors to take advantage of this sort of strategy. And we’re working right now on scaling up these systems.”

      While their experiments so far were done with a two-dimensional planar electrode, most industrial reactions are run in three-dimensional vessels filled with powders. Catalysts are distributed through those powders, providing a lot more surface area for the reactions to take place. “We’re looking at how catalysis is currently done in industry and how we can design systems that take advantage of the already existing infrastructure,” Westendorff says.

      Surendranath adds that these new findings “raise tantalizing possibilities: Is this a more general phenomenon? Does electrochemical potential play a key role in other reaction classes as well? In our mind, this reshapes how we think about designing catalysts and promoting their reactivity.”

      Roman-Leshkov adds that “traditionally people who work in thermochemical catalysis would not associate these reactions with electrochemical processes at all. However, introducing this perspective to the community will redefine how we can integrate electrochemical characteristics into thermochemical catalysis. It will have a big impact on the community in general.”

      While there has typically been little interaction between electrochemical and thermochemical catalysis researchers, Surendranath says, “this study shows the community that there’s really a blurring of the line between the two, and that there is a huge opportunity in cross-fertilization between these two communities.”

      Westerndorff adds that to make it work, “you have to design a system that’s pretty unconventional to either community to isolate this effect.” And that helps explain why such a dramatic effect had never been seen before. He notes that even their paper’s editor asked them why this effect hadn’t been reported before. The answer has to do with “how disparate those two ideologies were before this,” he says. “It’s not just that people don’t really talk to each other. There are deep methodological differences between how the two communities conduct experiments. And this work is really, we think, a great step toward bridging the two.”

      In practice, the findings could lead to far more efficient production of a wide variety of chemical materials, the team says. “You get orders of magnitude changes in rate with very little energy input,” Surendranath says. “That’s what’s amazing about it.”

      The findings, he says, “build a more holistic picture of how catalytic reactions at interfaces work, irrespective of whether you’re going to bin them into the category of electrochemical reactions or thermochemical reactions.” He adds that “it’s rare that you find something that could really revise our foundational understanding of surface catalytic reactions in general. We’re very excited.”

      “This research is of the highest quality,” says Costas Vayenas, a professor of engineering at the university of Patras, in Greece, who was not associated with the study. The work “is very promising for practical applications, particularly since it extends previous related work in redox catalytic systems,” he says.

      The team included MIT postdoc Max Hulsey PhD ’22 and graduate student Thejas Wesley PhD ’23, and was supported by the Air Force Office of Scientific Research and the U.S. Department of Energy Basic Energy Sciences. More

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      Working to beat the clock on climate change

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      “There’s so much work ahead of us and so many obstacles in the way,” said Raisa Lee, director of project development with Clearway Energy Group, an independent clean power producer. But, added Lee, “It’s most important to focus on finding spaces and people so we can foster growth and support each other — the power of belonging!”

      These sentiments captured the spirit of the 12th annual Women in Clean Energy Education and Empowerment (C3E) Symposium and Awards, held recently at MIT. The conference is part of the C3E Initiative, which aims to connect women in clean energy, recognize the accomplishments of leaders across different fields, and engage more women in the enterprise of decarbonization.

      The conference topic, “Clearing hurdles to achieve net zero by 2050: Moving quickly, eliminating risks, and leaving no one behind,” spoke to the shared sense of urgency and commitment to community-building among the several hundred participants attending in person and online.

      As symposium speakers attested, the task of saving the world doesn’t seem as daunting when someone has your back.

      Melinda Baglio, chief investment officer and general counsel of the renewable energy finance firm  CleanCapital, said “I have several groups of women in my life … and whenever I am doing something really difficult, I like to close my eyes for a minute and imagine their hands right on my shoulders and just giving me that support and pushing me forward to do the thing that I need to do.”

      The C3E symposium was hosted by the MIT Energy Initiative (MITEI), which partners in the C3E Initiative with the U.S. Department of Energy (DoE), Stanford University’s Precourt Institute for Energy, and the Texas A&M Energy Institute.

      Gender diversity and emissions

      “Time is not on our side in the race to achieve net zero by 2050,” said Martha Broad, executive director of MITEI, in her opening remarks.“However, by increasing the gender diversity of the energy sector, we’re putting our best team forward to tackle this challenge.”

      Closing a pronounced gender gap in corporate leadership and legislative bodies would also help, she said. Research has demonstrated that improving gender diversity in the energy sector leads to stronger climate governance and innovation. In addition, Broad noted, a recent study showed that increasing gender diversity in legislative bodies results in stronger climate policy and “hence lowers CO2 emissions.”

      There was wide agreement that beating the clock on climate change means recruiting, training, and retaining a vast and diverse workforce. In talks and panels, symposium participants described their wide-ranging roles as leaders in this enterprise.

      “This is a very exciting time to be working in clean energy, and an exciting time to be doubling down on the work that C3E does, because clean energy technologies are ready,” said Kathleen Hogan, principal undersecretary for infrastructure at DoE. In her keynote address, Hogan highlighted “the amazing, historic funding through the bipartisan infrastructure law and Inflation Reduction Act, where we are putting ultimately trillions of dollars into clean energy.” This presents a “tremendous opportunity to grow the clean energy workforce … to pull in the next generation of women to advance this field of work, and to figure out how to deliver the maximum impact.”

      Gina McCarthy, who received the C3E Lifetime Achievement Award, rallied symposium participants to remain hopeful and engaged. “It’s all about a world of new possibilities, new partnerships we can create together,” said the former White House national climate advisor and Environmental Protection Agency administrator. “Use each milestone as an opportunity to pat ourselves on the back and be more passionate than ever before — that is how change happens.”

      “You belong”

      Other speakers provided ample evidence of passion and persistence in their pursuit of clean energy goals.

      C3E advocacy award winner and climate justice policy leader Jameka Hodnett works to ensure that historically underfunded Black communities benefit from decarbonization programs. Not all of her community contacts share her concerns about climate change or recognize the necessity of an energy transition. “This is difficult work, where I must be willing to stick my neck out and build relationships with others across differences,” she said.

      Remote and often marginalized communities in the United States and around the world pose other kinds of challenges. Wahleah Johns, director of DoE’s Office of Indian Energy Policy and Programs, described the loss of jobs on tribal lands as fossil fuel companies shut down, and the problem of developing trust with local groups. She believes energy justice in these communities must draw “on Indigenous, traditional knowledge of design, building, and planning” and demonstrate “value for future generations.”

      Evangelina Galvan Shreeve, daughter of immigrant farm workers, is tapping the talent of diverse communities to build the next generation’s clean energy workforce. The C3E education award winner, chief diversity officer, and director of STEM education at the Pacific Northwest National Laboratory tells young people: “You are worthy of joining places you dream about, you are brilliant, and we need both to pursue the clean energy future. You belong.”

      Reducing the carbon budget

      In her keynote address, Sally M. Benson, the Precourt Family Professor of Energy Science Engineering at Stanford University’s School of Earth, Energy, and Environmental Sciences, warned of the hazards of not acting quickly to reduce the global carbon budget. “It’s starting to cost us lots of money: In some years we are getting half a trillion dollars in damage,” she said. “We need all hands on deck, and to do that we need to align people’s views to give us the speed and scale to beat incredibly short timelines.”

      Benson’s strategies include generating community- and city-scale, rather than individual-scale actions; streamlining the process for approving renewable energy projects; and advancing technological innovations based on “which would have the largest, transformational impact, the kind that could meet our 2050 [net-zero carbon emissions] goals.”

      The symposium offered examples of innovations that could play out at the scale and speed that Benson recommends. 

      Elise Strobach SM ’17, PhD ’20 developed a nanoporous nanogel coating for windows that can cut energy losses — estimated at $40 billion a year — in half. Her spinout company, AeroShield Materials, aims to make windows light, thin, and affordable.

      Claire Woo’s startup employer, Form Energy, has designed an iron-air battery that could bolster the electric grid as renewable sources such as sun and wind fuel more of the world’s energy needs. Stacked like so many blocks in giant arrays, the batteries provide 100-hour energy backup for multi-day power outages due to storms or other emergencies.

      Grids and energy equity

      Panelists discussed the requirements for resilient electric grids in the clean energy transition. Peggy Heeg, a corporate board member of the Electric Reliability Council of Texas (ERCOT), celebrated her state’s top-ranked status in solar and wind production but cautioned that “the shift is creating some real problems with our operations of the grid.” She believes that, currently, the only viable backup when heat or storms cause demand peaks is natural gas generation.

      Caroline Choi, the senior vice president of corporate affairs at Edison International and Southern California Edison, described “unprecedented grid expansion” under way in California, as more solar and wind suppliers plug in. This will require “a significant acceleration in the pace of deployment of transmission systems,” said Julie Mulvaney Kemp, a research scientist at Lawrence Berkeley National Laboratory. Such expansion is complicated by fragmented regional planning, high costs, and local siting issues.

      Not all power systems are super-sized. “I flew in small bush planes with my baby daughter in order to shadow Alaska microgrid operators,” said Piper Foster Wilder, founder and CEO of 60Hertz Energy and the C3E entrepreneurship award winner. Her software enables energy suppliers in even the most inaccessible places to monitor and protect utilities and infrastructure.

      “Given the fundamental aspects of energy for life, the widely entrenched nature of the energy system, and the intersecting challenges with other priorities, everyone has a vital role to play,” said Kathleen Araújo, a professor of sustainable energy systems, innovation, and policy at Boise State University. In a panel devoted to energy justice, speakers hammered home the centrality of historically marginalized groups in achieving a global energy transition.

      In the United States, communities must play a vital role in shaping their clean energy futures, whether former mining counties in Pennsylvania, Indian tribes whose lands have been exploited for fossil fuel production, or diesel-importing regions in Alaska, said Araújo. “Inclusive engagement, knowledge sharing, and other forms of collaboration can strengthen the legitimacy and [lead to] more enduring outcomes.”

      Worldwide, 675 million people lack access to electricity, and 590 million of them live in sub-Saharan Africa, according to Rhonda Jordan Antoine, a senior energy specialist at The World Bank. The bank is committed to providing the populace of this vast region with reliable, renewable energy sources, customizing solutions to specific countries and communities. “Africa’s not just about connecting households to power but also supporting activities, agricultural productivity, and provision of essential services such as health care and education,” she said.

      Whether confronting environmental injustice, supply chain gridlock, financing difficulties or communities resistant to addressing decarbonization, symposium participants candidly shared their challenges and frustrations. “I personally find this is really hard work,” Sally Benson acknowledged. “It took us 100 years or more to build the energy system that we have today and now we’re saying that we want to change it in the next 20 years.”

      But the words of Gina McCarthy were invoked repeatedly over the two-day conference, lifting spirits in the room: “I am hugely optimistic,” she said. “The clean energy future isn’t just around, it isn’t just possible, it is already under way. And it is the opportunity of a lifetime.” More

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      How to decarbonize the world, at scale

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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      in Energy

      Engineers develop an efficient process to make fuel from carbon dioxide

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      The search is on worldwide to find ways to extract carbon dioxide from the air or from power plant exhaust and then make it into something useful. One of the more promising ideas is to make it into a stable fuel that can replace fossil fuels in some applications. But most such conversion processes have had problems with low carbon efficiency, or they produce fuels that can be hard to handle, toxic, or flammable.

      Now, researchers at MIT and Harvard University have developed an efficient process that can convert carbon dioxide into formate, a liquid or solid material that can be used like hydrogen or methanol to power a fuel cell and generate electricity. Potassium or sodium formate, already produced at industrial scales and commonly used as a de-icer for roads and sidewalks, is nontoxic, nonflammable, easy to store and transport, and can remain stable in ordinary steel tanks to be used months, or even years, after its production.

      The new process, developed by MIT doctoral students Zhen Zhang, Zhichu Ren, and Alexander H. Quinn; Harvard University doctoral student Dawei Xi; and MIT Professor Ju Li, is described this week in an open-access paper in Cell Reports Physical Science. The whole process — including capture and electrochemical conversion of the gas to a solid formate powder, which is then used in a fuel cell to produce electricity — was demonstrated at a small, laboratory scale. However, the researchers expect it to be scalable so that it could provide emissions-free heat and power to individual homes and even be used in industrial or grid-scale applications.

      Other approaches to converting carbon dioxide into fuel, Li explains, usually involve a two-stage process: First the gas is chemically captured and turned into a solid form as calcium carbonate, then later that material is heated to drive off the carbon dioxide and convert it to a fuel feedstock such as carbon monoxide. That second step has very low efficiency, typically converting less than 20 percent of the gaseous carbon dioxide into the desired product, Li says.

      By contrast, the new process achieves a conversion of well over 90 percent and eliminates the need for the inefficient heating step by first converting the carbon dioxide into an intermediate form, liquid metal bicarbonate. That liquid is then electrochemically converted into liquid potassium or sodium formate in an electrolyzer that uses low-carbon electricity, e.g. nuclear, wind, or solar power. The highly concentrated liquid potassium or sodium formate solution produced can then be dried, for example by solar evaporation, to produce a solid powder that is highly stable and can be stored in ordinary steel tanks for up to years or even decades, Li says.

      Several steps of optimization developed by the team made all the difference in changing an inefficient chemical-conversion process into a practical solution, says Li, who holds joint appointments in the departments of Nuclear Science and Engineering and of Materials Science and Engineering.

      The process of carbon capture and conversion involves first an alkaline solution-based capture that concentrates carbon dioxide, either from concentrated streams such as from power plant emissions or from very low-concentration sources, even open air, into the form of a liquid metal-bicarbonate solution. Then, through the use of a cation-exchange membrane electrolyzer, this bicarbonate is electrochemically converted into solid formate crystals with a carbon efficiency of greater than 96 percent, as confirmed in the team’s lab-scale experiments.

      These crystals have an indefinite shelf life, remaining so stable that they could be stored for years, or even decades, with little or no loss. By comparison, even the best available practical hydrogen storage tanks allow the gas to leak out at a rate of about 1 percent per day, precluding any uses that would require year-long storage, Li says. Methanol, another widely explored alternative for converting carbon dioxide into a fuel usable in fuel cells, is a toxic substance that cannot easily be adapted to use in situations where leakage could pose a health hazard. Formate, on the other hand, is widely used and considered benign, according to national safety standards.

      Several improvements account for the greatly improved efficiency of this process. First, a careful design of the membrane materials and their configuration overcomes a problem that previous attempts at such a system have encountered, where a buildup of certain chemical byproducts changes the pH, causing the system to steadily lose efficiency over time. “Traditionally, it is difficult to achieve long-term, stable, continuous conversion of the feedstocks,” Zhang says. “The key to our system is to achieve a pH balance for steady-state conversion.”

      To achieve that, the researchers carried out thermodynamic modeling to design the new process so that it is chemically balanced and the pH remains at a steady state with no shift in acidity over time. It can therefore continue operating efficiently over long periods. In their tests, the system ran for over 200 hours with no significant decrease in output. The whole process can be done at ambient temperatures and relatively low pressures (about five times atmospheric pressure).

      Another issue was that unwanted side reactions produced other chemical products that were not useful, but the team figured out a way to prevent these side reactions by the introduction of an extra “buffer” layer of bicarbonate-enriched fiberglass wool that blocked these reactions.

      The team also built a fuel cell specifically optimized for the use of this formate fuel to produce electricity. The stored formate particles are simply dissolved in water and pumped into the fuel cell as needed. Although the solid fuel is much heavier than pure hydrogen, when the weight and volume of the high-pressure gas tanks needed to store hydrogen is considered, the end result is an electricity output near parity for a given storage volume, Li says.

      The formate fuel can potentially be adapted for anything from home-sized units to large scale industrial uses or grid-scale storage systems, the researchers say. Initial household applications might involve an electrolyzer unit about the size of a refrigerator to capture and convert the carbon dioxide into formate, which could be stored in an underground or rooftop tank. Then, when needed, the powdered solid would be mixed with water and fed into a fuel cell to provide power and heat. “This is for community or household demonstrations,” Zhang says, “but we believe that also in the future it may be good for factories or the grid.”

      “The formate economy is an intriguing concept because metal formate salts are very benign and stable, and a compelling energy carrier,” says Ted Sargent, a professor of chemistry and of electrical and computer engineering at Northwestern University, who was not associated with this work. “The authors have demonstrated enhanced efficiency in liquid-to-liquid conversion from bicarbonate feedstock to formate, and have demonstrated these fuels can be used later to produce electricity,” he says.

      The work was supported by the U.S. Department of Energy Office of Science. More

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      in Energy

      Fast-tracking fusion energy’s arrival with AI and accessibility

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      As the impacts of climate change continue to grow, so does interest in fusion’s potential as a clean energy source. While fusion reactions have been studied in laboratories since the 1930s, there are still many critical questions scientists must answer to make fusion power a reality, and time is of the essence. As part of their strategy to accelerate fusion energy’s arrival and reach carbon neutrality by 2050, the U.S. Department of Energy (DoE) has announced new funding for a project led by researchers at MIT’s Plasma Science and Fusion Center (PSFC) and four collaborating institutions.

      Cristina Rea, a research scientist and group leader at the PSFC, will serve as the primary investigator for the newly funded three-year collaboration to pilot the integration of fusion data into a system that can be read by AI-powered tools. The PSFC, together with scientists from the College of William and Mary, the University of Wisconsin at Madison, Auburn University, and the nonprofit HDF Group, plan to create a holistic fusion data platform, the elements of which could offer unprecedented access for researchers, especially underrepresented students. The project aims to encourage diverse participation in fusion and data science, both in academia and the workforce, through outreach programs led by the group’s co-investigators, of whom four out of five are women. 

      The DoE’s award, part of a $29 million funding package for seven projects across 19 institutions, will support the group’s efforts to distribute data produced by fusion devices like the PSFC’s Alcator C-Mod, a donut-shaped “tokamak” that utilized powerful magnets to control and confine fusion reactions. Alcator C-Mod operated from 1991 to 2016 and its data are still being studied, thanks in part to the PSFC’s commitment to the free exchange of knowledge.

      Currently, there are nearly 50 public experimental magnetic confinement-type fusion devices; however, both historical and current data from these devices can be difficult to access. Some fusion databases require signing user agreements, and not all data are catalogued and organized the same way. Moreover, it can be difficult to leverage machine learning, a class of AI tools, for data analysis and to enable scientific discovery without time-consuming data reorganization. The result is fewer scientists working on fusion, greater barriers to discovery, and a bottleneck in harnessing AI to accelerate progress.

      The project’s proposed data platform addresses technical barriers by being FAIR — Findable, Interoperable, Accessible, Reusable — and by adhering to UNESCO’s Open Science (OS) recommendations to improve the transparency and inclusivity of science; all of the researchers’ deliverables will adhere to FAIR and OS principles, as required by the DoE. The platform’s databases will be built using MDSplusML, an upgraded version of the MDSplus open-source software developed by PSFC researchers in the 1980s to catalogue the results of Alcator C-Mod’s experiments. Today, nearly 40 fusion research institutes use MDSplus to store and provide external access to their fusion data. The release of MDSplusML aims to continue that legacy of open collaboration.

      The researchers intend to address barriers to participation for women and disadvantaged groups not only by improving general access to fusion data, but also through a subsidized summer school that will focus on topics at the intersection of fusion and machine learning, which will be held at William and Mary for the next three years.

      Of the importance of their research, Rea says, “This project is about responding to the fusion community’s needs and setting ourselves up for success. Scientific advancements in fusion are enabled via multidisciplinary collaboration and cross-pollination, so accessibility is absolutely essential. I think we all understand now that diverse communities have more diverse ideas, and they allow faster problem-solving.”

      The collaboration’s work also aligns with vital areas of research identified in the International Atomic Energy Agency’s “AI for Fusion” Coordinated Research Project (CRP). Rea was selected as the technical coordinator for the IAEA’s CRP emphasizing community engagement and knowledge access to accelerate fusion research and development. In a letter of support written for the group’s proposed project, the IAEA stated that, “the work [the researchers] will carry out […] will be beneficial not only to our CRP but also to the international fusion community in large.”

      PSFC Director and Hitachi America Professor of Engineering Dennis Whyte adds, “I am thrilled to see PSFC and our collaborators be at the forefront of applying new AI tools while simultaneously encouraging and enabling extraction of critical data from our experiments.”

      “Having the opportunity to lead such an important project is extremely meaningful, and I feel a responsibility to show that women are leaders in STEM,” says Rea. “We have an incredible team, strongly motivated to improve our fusion ecosystem and to contribute to making fusion energy a reality.” More

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      in Energy

      To improve solar and other clean energy tech, look beyond hardware

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      To continue reducing the costs of solar energy and other clean energy technologies, scientists and engineers will likely need to focus, at least in part, on improving technology features that are not based on hardware, according to MIT researchers. They describe this finding and the mechanisms behind it today in Nature Energy.

      While the cost of installing a solar energy system has dropped by more than 99 percent since 1980, this new analysis shows that “soft technology” features, such as the codified permitting practices, supply chain management techniques, and system design processes that go into deploying a solar energy plant, contributed only 10 to 15 percent of total cost declines. Improvements to hardware features were responsible for the lion’s share.

      But because soft technology is increasingly dominating the total costs of installing solar energy systems, this trend threatens to slow future cost savings and hamper the global transition to clean energy, says the study’s senior author, Jessika Trancik, a professor in MIT’s Institute for Data, Systems, and Society (IDSS).

      Trancik’s co-authors include lead author Magdalena M. Klemun, a former IDSS graduate student and postdoc who is now an assistant professor at the Hong Kong University of Science and Technology; Goksin Kavlak, a former IDSS graduate student and postdoc who is now an associate at the Brattle Group; and James McNerney, a former IDSS postdoc and now senior research fellow at the Harvard Kennedy School.

      The team created a quantitative model to analyze the cost evolution of solar energy systems, which captures the contributions of both hardware technology features and soft technology features.

      The framework shows that soft technology hasn’t improved much over time — and that soft technology features contributed even less to overall cost declines than previously estimated.

      Their findings indicate that to reverse this trend and accelerate cost declines, engineers could look at making solar energy systems less reliant on soft technology to begin with, or they could tackle the problem directly by improving inefficient deployment processes.  

      “Really understanding where the efficiencies and inefficiencies are, and how to address those inefficiencies, is critical in supporting the clean energy transition. We are making huge investments of public dollars into this, and soft technology is going to be absolutely essential to making those funds count,” says Trancik.

      “However,” Klemun adds, “we haven’t been thinking about soft technology design as systematically as we have for hardware. That needs to change.”

      The hard truth about soft costs

      Researchers have observed that the so-called “soft costs” of building a solar power plant — the costs of designing and installing the plant — are becoming a much larger share of total costs. In fact, the share of soft costs now typically ranges from 35 to 64 percent.

      “We wanted to take a closer look at where these soft costs were coming from and why they weren’t coming down over time as quickly as the hardware costs,” Trancik says.

      In the past, scientists have modeled the change in solar energy costs by dividing total costs into additive components — hardware components and nonhardware components — and then tracking how these components changed over time.

      “But if you really want to understand where those rates of change are coming from, you need to go one level deeper to look at the technology features. Then things split out differently,” Trancik says.

      The researchers developed a quantitative approach that models the change in solar energy costs over time by assigning contributions to the individual technology features, including both hardware features and soft technology features.

      For instance, their framework would capture how much of the decline in system installation costs — a soft cost — is due to standardized practices of certified installers — a soft technology feature. It would also capture how that same soft cost is affected by increased photovoltaic module efficiency — a hardware technology feature.

      With this approach, the researchers saw that improvements in hardware had the greatest impacts on driving down soft costs in solar energy systems. For example, the efficiency of photovoltaic modules doubled between 1980 and 2017, reducing overall system costs by 17 percent. But about 40 percent of that overall decline could be attributed to reductions in soft costs tied to improved module efficiency.

      The framework shows that, while hardware technology features tend to improve many cost components, soft technology features affect only a few.

      “You can see this structural difference even before you collect data on how the technologies have changed over time. That’s why mapping out a technology’s network of cost dependencies is a useful first step to identify levers of change, for solar PV and for other technologies as well,” Klemun notes.  

      Static soft technology

      The researchers used their model to study several countries, since soft costs can vary widely around the world. For instance, solar energy soft costs in Germany are about 50 percent less than those in the U.S.

      The fact that hardware technology improvements are often shared globally led to dramatic declines in costs over the past few decades across locations, the analysis showed. Soft technology innovations typically aren’t shared across borders. Moreover, the team found that countries with better soft technology performance 20 years ago still have better performance today, while those with worse performance didn’t see much improvement.

      This country-by-country difference could be driven by regulation and permitting processes, cultural factors, or by market dynamics such as how firms interact with each other, Trancik says.

      “But not all soft technology variables are ones that you would want to change in a cost-reducing direction, like lower wages. So, there are other considerations, beyond just bringing the cost of the technology down, that we need to think about when interpreting these results,” she says.

      Their analysis points to two strategies for reducing soft costs. For one, scientists could focus on developing hardware improvements that make soft costs more dependent on hardware technology variables and less on soft technology variables, such as by creating simpler, more standardized equipment that could reduce on-site installation time.

      Or researchers could directly target soft technology features without changing hardware, perhaps by creating more efficient workflows for system installation or automated permitting platforms.

      “In practice, engineers will often pursue both approaches, but separating the two in a formal model makes it easier to target innovation efforts by leveraging specific relationships between technology characteristics and costs,” Klemun says.

      “Often, when we think about information processing, we are leaving out processes that still happen in a very low-tech way through people communicating with one another. But it is just as important to think about that as a technology as it is to design fancy software,” Trancik notes.

      In the future, she and her collaborators want to apply their quantitative model to study the soft costs related to other technologies, such as electrical vehicle charging and nuclear fission. They are also interested in better understanding the limits of soft technology improvement, and how one could design better soft technology from the outset.

      This research is funded by the U.S. Department of Energy Solar Energy Technologies Office. More

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      in Energy

      Chemists discover why photosynthetic light-harvesting is so efficient

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      When photosynthetic cells absorb light from the sun, packets of energy called photons leap between a series of light-harvesting proteins until they reach the photosynthetic reaction center. There, cells convert the energy into electrons, which eventually power the production of sugar molecules.

      This transfer of energy through the light-harvesting complex occurs with extremely high efficiency: Nearly every photon of light absorbed generates an electron, a phenomenon known as near-unity quantum efficiency.

      A new study from MIT chemists offers a potential explanation for how proteins of the light-harvesting complex, also called the antenna, achieve that high efficiency. For the first time, the researchers were able to measure the energy transfer between light-harvesting proteins, allowing them to discover that the disorganized arrangement of these proteins boosts the efficiency of the energy transduction.

      “In order for that antenna to work, you need long-distance energy transduction. Our key finding is that the disordered organization of the light-harvesting proteins enhances the efficiency of that long-distance energy transduction,” says Gabriela Schlau-Cohen, an associate professor of chemistry at MIT and the senior author of the new study.

      MIT postdocs Dihao Wang and Dvir Harris and former MIT graduate student Olivia Fiebig PhD ’22 are the lead authors of the paper, which appears this week in the Proceedings of the National Academy of Sciences. Jianshu Cao, an MIT professor of chemistry, is also an author of the paper.

      Energy capture

      For this study, the MIT team focused on purple bacteria, which are often found in oxygen-poor aquatic environments and are commonly used as a model for studies of photosynthetic light-harvesting.

      Within these cells, captured photons travel through light-harvesting complexes consisting of proteins and light-absorbing pigments such as chlorophyll. Using ultrafast spectroscopy, a technique that uses extremely short laser pulses to study events that happen on timescales of femtoseconds to nanoseconds, scientists have been able to study how energy moves within a single one of these proteins. However, studying how energy travels between these proteins has proven much more challenging because it requires positioning multiple proteins in a controlled way.

      To create an experimental setup where they could measure how energy travels between two proteins, the MIT team designed synthetic nanoscale membranes with a composition similar to those of naturally occurring cell membranes. By controlling the size of these membranes, known as nanodiscs, they were able to control the distance between two proteins embedded within the discs.

      For this study, the researchers embedded two versions of the primary light-harvesting protein found in purple bacteria, known as LH2 and LH3, into their nanodiscs. LH2 is the protein that is present during normal light conditions, and LH3 is a variant that is usually expressed only during low light conditions.

      Using the cryo-electron microscope at the MIT.nano facility, the researchers could image their membrane-embedded proteins and show that they were positioned at distances similar to those seen in the native membrane. They were also able to measure the distances between the light-harvesting proteins, which were on the scale of 2.5 to 3 nanometers.

      Disordered is better

      Because LH2 and LH3 absorb slightly different wavelengths of light, it is possible to use ultrafast spectroscopy to observe the energy transfer between them. For proteins spaced closely together, the researchers found that it takes about 6 picoseconds for a photon of energy to travel between them. For proteins farther apart, the transfer takes up to 15 picoseconds.

      Faster travel translates to more efficient energy transfer, because the longer the journey takes, the more energy is lost during the transfer.

      “When a photon gets absorbed, you only have so long before that energy gets lost through unwanted processes such as nonradiative decay, so the faster it can get converted, the more efficient it will be,” Schlau-Cohen says.

      The researchers also found that proteins arranged in a lattice structure showed less efficient energy transfer than proteins that were arranged in randomly organized structures, as they usually are in living cells.

      “Ordered organization is actually less efficient than the disordered organization of biology, which we think is really interesting because biology tends to be disordered. This finding tells us that that may not just be an inevitable downside of biology, but organisms may have evolved to take advantage of it,” Schlau-Cohen says.

      Now that they have established the ability to measure inter-protein energy transfer, the researchers plan to explore energy transfer between other proteins, such as the transfer between proteins of the antenna to proteins of the reaction center. They also plan to study energy transfer between antenna proteins found in organisms other than purple bacteria, such as green plants.

      The research was funded primarily by the U.S. Department of Energy. More

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      in Environment

      Exploring the bow shock and beyond

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

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

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

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

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

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

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

      Gathering measurements from MAGPIE

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

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

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

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

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

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

      Onward to Z

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

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

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

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

      Pursuing climate action at MIT

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

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

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

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