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    Smart handling of neutrons is crucial to fusion power success

    In fall 2009, when Ethan Peterson ’13 arrived at MIT as an undergraduate, he already had some ideas about possible career options. He’d always liked building things, even as a child, so he imagined his future work would involve engineering of some sort. He also liked physics. And he’d recently become intent on reducing our dependence on fossil fuels and simultaneously curbing greenhouse gas emissions, which made him consider studying solar and wind energy, among other renewable sources.Things crystallized for him in the spring semester of 2010, when he took an introductory course on nuclear fusion, taught by Anne White, during which he discovered that when a deuterium nucleus and a tritium nucleus combine to produce a helium nucleus, an energetic (14 mega electron volt) neutron — traveling at one-sixth the speed of light — is released. Moreover, 1020 (100 billion billion) of these neutrons would be produced every second that a 500-megawatt fusion power plant operates. “It was eye-opening for me to learn just how energy-dense the fusion process is,” says Peterson, who became the Class of 1956 Career Development Professor of nuclear science and engineering in July 2024. “I was struck by the richness and interdisciplinary nature of the fusion field. This was an engineering discipline where I could apply physics to solve a real-world problem in a way that was both interesting and beautiful.”He soon became a physics and nuclear engineering double major, and by the time he graduated from MIT in 2013, the U.S. Department of Energy (DoE) had already decided to cut funding for MIT’s Alcator C-Mod fusion project. In view of that facility’s impending closure, Peterson opted to pursue graduate studies at the University of Wisconsin. There, he acquired a basic science background in plasma physics, which is central not only to nuclear fusion but also to astrophysical phenomena such as the solar wind.When Peterson received his PhD from Wisconsin in 2019, nuclear fusion had rebounded at MIT with the launch, a year earlier, of the SPARC project — a collaborative effort being carried out with the newly founded MIT spinout Commonwealth Fusion Systems. He returned to his alma mater as a postdoc and then a research scientist in the Plasma Science and Fusion Center, taking his time, at first, to figure out how to best make his mark in the field.Minding your neutronsAround that time, Peterson was participating in a community planning process, sponsored by the DoE, that focused on critical gaps that needed to be closed for a successful fusion program. In the course of these discussions, he came to realize that inadequate attention had been paid to the handling of neutrons, which carry 80 percent of the energy coming out of a fusion reaction — energy that needs to be harnessed for electrical generation. However, these neutrons are so energetic that they can penetrate through many tens of centimeters of material, potentially undermining the structural integrity of components and damaging vital equipment such as superconducting magnets. Shielding is also essential for protecting humans from harmful radiation.One goal, Peterson says, is to minimize the number of neutrons that escape and, in so doing, to reduce the amount of lost energy. A complementary objective, he adds, “is to get neutrons to deposit heat where you want them to and to stop them from depositing heat where you don’t want them to.” These considerations, in turn, can have a profound influence on fusion reactor design. This branch of nuclear engineering, called neutronics — which analyzes where neutrons are created and where they end up going — has become Peterson’s specialty.It was never a high-profile area of research in the fusion community — as plasma physics, for example, has always garnered more of the spotlight and more of the funding. That’s exactly why Peterson has stepped up. “The impacts of neutrons on fusion reactor design haven’t been a high priority for a long time,” he says. “I felt that some initiative needed to be taken,” and that prompted him to make the switch from plasma physics to neutronics. It has been his principal focus ever since — as a postdoc, a research scientist, and now as a faculty member.A code to design byThe best way to get a neutron to transfer its energy is to make it collide with a light atom. Lithium, with an atomic number of three, or lithium-containing materials are normally good choices — and necessary for producing tritium fuel. The placement of lithium “blankets,” which are intended to absorb energy from neutrons and produce tritium, “is a critical part of the design of fusion reactors,” Peterson says. High-density materials, such as lead and tungsten, can be used, conversely, to block the passage of neutrons and other types of radiation. “You might want to layer these high- and low-density materials in a complicated way that isn’t immediately intuitive” he adds. Determining which materials to put where — and of what thickness and mass — amounts to a tricky optimization problem, which will affect the size, cost, and efficiency of a fusion power plant.To that end, Peterson has developed modelling tools that can make analyses of these sorts easier and faster, thereby facilitating the design process. “This has traditionally been the step that takes the longest time and causes the biggest holdups,” he says. The models and algorithms that he and his colleagues are devising are general enough, moreover, to be compatible with a diverse range of fusion power plant concepts, including those that use magnets or lasers to confine the plasma.Now that he’s become a professor, Peterson is in a position to introduce more people to nuclear engineering, and to neutronics in particular. “I love teaching and mentoring students, sharing the things I’m excited about,” he says. “I was inspired by all the professors I had in physics and nuclear engineering at MIT, and I hope to give back to the community in the same way.”He also believes that if you are going to work on fusion, there is no better place to be than MIT, “where the facilities are second-to-none. People here are extremely innovative and passionate. And the sheer number of people who excel in their fields is staggering.” Great ideas can sometimes be sparked by off-the-cuff conversations in the hallway — something that happens more frequently than you expect, Peterson remarks. “All of these things taken together makes MIT a very special place.” More

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    3 Questions: Can we secure a sustainable supply of nickel?

    As the world strives to cut back on carbon emissions, demand for minerals and metals needed for clean energy technologies is growing rapidly, sometimes straining existing supply chains and harming local environments. In a new study published today in Joule, Elsa Olivetti, a professor of materials science and engineering and director of the Decarbonizing Energy and Industry mission within MIT’s Climate Project, along with recent graduates Basuhi Ravi PhD ’23 and Karan Bhuwalka PhD ’24 and nine others, examine the case of nickel, which is an essential element for some electric vehicle batteries and parts of some solar panels and wind turbines.How robust is the supply of this vital metal, and what are the implications of its extraction for the local environments, economies, and communities in the places where it is mined? MIT News asked Olivetti, Ravi, and Bhuwalka to explain their findings.Q: Why is nickel becoming more important in the clean energy economy, and what are some of the potential issues in its supply chain?Olivetti: Nickel is increasingly important for its role in EV batteries, as well as other technologies such as wind and solar. For batteries, high-purity nickel sulfate is a key input to the cathodes of EV batteries, which enables high energy density in batteries and increased driving range for EVs. As the world transitions away from fossil fuels, the demand for EVs, and consequently for nickel, has increased dramatically and is projected to continue to do so.The nickel supply chain for battery-grade nickel sulfate includes mining nickel from ore deposits, processing it to a suitable nickel intermediary, and refining it to nickel sulfate. The potential issues in the supply chain can be broadly described as land use concerns in the mining stage, and emissions concerns in the processing stage. This is obviously oversimplified, but as a basic structure for our inquiry we thought about it this way. Nickel mining is land-intensive, leading to deforestation, displacement of communities, and potential contamination of soil and water resources from mining waste. In the processing step, the use of fossil fuels leads to direct emissions including particulate matter and sulfur oxides. In addition, some emerging processing pathways are particularly energy-intensive, which can double the carbon footprint of nickel-rich batteries compared to the current average.Q: What is Indonesia’s role in the global nickel supply, and what are the consequences of nickel extraction there and in other major supply countries?Ravi: Indonesia plays a critical role in nickel supply, holding the world’s largest nickel reserves and supplying nearly half of the globally mined nickel in 2023. The country’s nickel production has seen a remarkable tenfold increase since 2016. This production surge has fueled economic growth in some regions, but also brought notable environmental and social impacts to nickel mining and processing areas.Nickel mining expansion in Indonesia has been linked to health impacts due to air pollution in the islands where nickel processing is prominent, as well as deforestation in some of the most biodiversity-rich locations on the planet. Reports of displacement of indigenous communities, land grabbing, water rights issues, and inadequate job quality in and around mines further highlight the social concerns and unequal distribution of burdens and benefits in Indonesia. Similar concerns exist in other major nickel-producing countries, where mining activities can negatively impact the environment, disrupt livelihoods, and exacerbate inequalities.On a global scale, Indonesia’s reliance on coal-based energy for nickel processing, particularly in energy-intensive smelting and leaching of a clay-like material called laterite, results in a high carbon intensity for nickel produced in the region, compared to other major producing regions such as Australia.Q: What role can industry and policymakers play in helping to meet growing demand while improving environmental safety?Bhuwalka: In consuming countries, policies can foster “discerning demand,” which means creating incentives for companies to source nickel from producers that prioritize sustainability. This can be achieved through regulations that establish acceptable environmental footprints for imported materials, such as limits on carbon emissions from nickel production. For example, the EU’s Critical Raw Materials Act and the U.S. Inflation Reduction Act could be leveraged to promote responsible sourcing. Additionally, governments can use their purchasing power to favor sustainably produced nickel in public procurement, which could influence industry practices and encourage the adoption of sustainability standards.On the supply side, nickel-producing countries like Indonesia can implement policies to mitigate the adverse environmental and social impacts of nickel extraction. This includes strengthening environmental regulations and enforcement to reduce the footprint of mining and processing, potentially through stricter pollution limits and responsible mine waste management. In addition, supporting community engagement, implementing benefit-sharing mechanisms, and investing in cleaner nickel processing technologies are also crucial.Internationally, harmonizing sustainability standards and facilitating capacity building and technology transfer between developed and developing countries can create a level playing field and prevent unsustainable practices. Responsible investment practices by international financial institutions, favoring projects that meet high environmental and social standards, can also contribute to a stable and sustainable nickel supply chain. More

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    Making agriculture more resilient to climate change

    As Earth’s temperature rises, agricultural practices will need to adapt. Droughts will likely become more frequent, and some land may no longer be arable. On top of that is the challenge of feeding an ever-growing population without expanding the production of fertilizer and other agrochemicals, which have a large carbon footprint that is contributing to the overall warming of the planet.Researchers across MIT are taking on these agricultural challenges from a variety of angles, from engineering plants that sound an alarm when they’re under stress to making seeds more resilient to drought. These types of technologies, and more yet to be devised, will be essential to feed the world’s population as the climate changes.“After water, the first thing we need is food. In terms of priority, there is water, food, and then everything else. As we are trying to find new strategies to support a world of 10 billion people, it will require us to invent new ways of making food,” says Benedetto Marelli, an associate professor of civil and environmental engineering at MIT.Marelli is the director of one of the six missions of the recently launched Climate Project at MIT, which focus on research areas such as decarbonizing industry and building resilient cities. Marelli directs the Wild Cards mission, which aims to identify unconventional solutions that are high-risk and high-reward.Drawing on expertise from a breadth of fields, MIT is well-positioned to tackle the challenges posed by climate change, Marelli says. “Bringing together our strengths across disciplines, including engineering, processing at scale, biological engineering, and infrastructure engineering, along with humanities, science, and economics, presents a great opportunity.”Protecting seeds from droughtMarelli, who began his career as a biomedical engineer working on regenerative medicine, is now developing ways to boost crop yields by helping seeds to survive and germinate during drought conditions, or in soil that has been depleted of nutrients. To achieve that, he has devised seed coatings, based on silk and other polymers, that can envelop and nourish seeds during the critical germination process.

    A new seed-coating process could facilitate agriculture on marginal arid lands by enabling the seeds to retain any available water.

    In healthy soil, plants have access to nitrogen, phosphates, and other nutrients that they need, many of which are supplied by microbes that live in the soil. However, in soil that has suffered from drought or overfarming, these nutrients are lacking. Marelli’s idea was to coat the seeds with a polymer that can be embedded with plant-growth-promoting bacteria that “fix” nitrogen by absorbing it from the air and making it available to plants. The microbes can also make other necessary nutrients available to plants.For the first generation of the seed coatings, he embedded these microbes in coatings made of silk — a material that he had previously shown can extend the shelf life of produce, meat, and other foods. In his lab at MIT, Marelli has shown that the seed coatings can help germinating plants survive drought, ultraviolet light exposure, and high salinity.Now, working with researchers at the Mohammed VI Polytechnic University in Morocco, he is adapting the approach to crops native to Morocco, a country that has experienced six consecutive years of drought due a drop in rainfall linked to climate change.For these studies, the researchers are using a biopolymer coating derived from food waste that can be easily obtained in Morocco, instead of silk.“We’re working with local communities to extract the biopolymers, to try to have a process that works at scale so that we make materials that work in that specific environment.” Marelli says. “We may come up with an idea here at MIT within a high-resource environment, but then to work there, we need to talk with the local communities, with local stakeholders, and use their own ingenuity and try to match our solution with something that could actually be applied in the local environment.”Microbes as fertilizersWhether they are experiencing drought or not, crops grow much better when synthetic fertilizers are applied. Although it’s essential to most farms, applying fertilizer is expensive and has environmental consequences. Most of the world’s fertilizer is produced using the Haber-Bosch process, which converts nitrogen and hydrogen to ammonia at high temperatures and pressures. This energy intensive process accounts for about 1.5 percent of the world’s greenhouse gas emissions, and the transportation required to deliver it to farms around the world adds even more emissions.Ariel Furst, the Paul M. Cook Career Development Assistant Professor of Chemical Engineering at MIT, is developing a microbial alternative to the Haber-Bosch process. Some farms have experimented with applying nitrogen-fixing bacteria directly to the roots of their crops, which has shown some success. However, the microbes are too delicate to be stored long-term or shipped anywhere, so they must be produced in a bioreactor on the farm.

    MIT chemical engineers devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function.

    To overcome those challenges, Furst has developed a way to coat the microbes with a protective shell that prevents them from being destroyed by heat or other stresses. The coating also protects microbes from damage caused by freeze-drying — a process that would make them easier to transport.The coatings can vary in composition, but they all consist of two components. One is a metal such as iron, manganese, or zinc, and the other is a polyphenol — a type of plant-derived organic compound that includes tannins and other antioxidants. These two components self-assemble into a protective shell that encapsulates bacteria.

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    Mighty Microbes: The Power of Protective PolymersVideo: Chemistry Shorts

    “These microbes would be delivered with the seeds, so it would remove the need for fertilizing mid-growing. It also reduces the cost and provides more autonomy to the farmers and decreases carbon emissions associated with agriculture,” Furst says. “We think it’ll be a way to make agriculture completely regenerative, so to bring back soil health while also boosting crop yields and the nutrient density of the crops.”Furst has founded a company called Seia Bio, which is working on commercializing the coated microbes and has begun testing them on farms in Brazil. In her lab, Furst is also working on adapting the approach to coat microbes that can capture carbon dioxide from the atmosphere and turn it into limestone, which helps to raise the soil pH.“It can help change the pH of soil to stabilize it, while also being a way to effectively perform direct air capture of CO2,” she says. “Right now, farmers may truck in limestone to change the pH of soil, and so you’re creating a lot of emissions to bring something in that microbes can do on their own.”Distress sensors for plantsSeveral years ago, Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT, began to explore the idea of using plants themselves as sensors that could reveal when they’re in distress. When plants experience drought, attack by pests, or other kinds of stress, they produce hormones and other signaling molecules to defend themselves.Strano, whose lab specializes in developing tiny sensors for a variety of molecules, wondered if such sensors could be deployed inside plants to pick up those distress signals. To create their sensors, Strano’s lab takes advantage of the special properties of single-walled carbon nanotubes, which emit fluorescent light. By wrapping the tubes with different types of polymers, the sensors can be tuned to detect specific targets, giving off a fluorescent signal when the target is present.For use in plants, Strano and his colleagues created sensors that could detect signaling molecules such as salicylic acid and hydrogen peroxide. They then showed that these sensors could be inserted into the underside of plant leaves, without harming the plants. Once embedded in the mesophyll of the leaves, the sensors can pick up a variety of signals, which can be read with an infrared camera.

    Sensors that detect plant signaling molecules can reveal when crops are experiencing too much light or heat, or attack from insects or microbes.

    These sensors can reveal, in real-time, whether a plant is experiencing a variety of stresses. Until now, there hasn’t been a way to get that information fast enough for farmers to act on it.“What we’re trying to do is make tools that get information into the hands of farmers very quickly, fast enough for them to make adaptive decisions that can increase yield,” Strano says. “We’re in the middle of a revolution of really understanding the way in which plants internally communicate and communicate with other plants.”This kind of sensing could be deployed in fields, where it could help farmers respond more quickly to drought and other stresses, or in greenhouses, vertical farms, and other types of indoor farms that use technology to grow crops in a controlled environment.Much of Strano’s work in this area has been conducted with the support of the U.S. Department of Agriculture (USDA) and as part of the Disruptive and Sustainable Technologies for Agricultural Precision (DiSTAP) program at the Singapore-MIT Alliance for Research and Technology (SMART), and sensors have been deployed in tests in crops at a controlled environment farm in Singapore called Growy.“The same basic kinds of tools can help detect problems in open field agriculture or in controlled environment agriculture,” Strano says. “They both suffer from the same problem, which is that the farmers get information too late to prevent yield loss.”Reducing pesticide usePesticides represent another huge financial expense for farmers: Worldwide, farmers spend about $60 billion per year on pesticides. Much of this pesticide ends up accumulating in water and soil, where it can harm many species, including humans. But, without using pesticides, farmers may lose more than half of their crops.Kripa Varanasi, an MIT professor of mechanical engineering, is working on tools that can help farmers measure how much pesticide is reaching their plants, as well as technologies that can help pesticides adhere to plants more efficiently, reducing the amount that runs off into soil and water.Varanasi, whose research focuses on interactions between liquid droplets and surfaces, began to think about applying his work to agriculture more than a decade ago, after attending a conference at the USDA. There, he was inspired to begin developing ways to improve the efficiency of pesticide application by optimizing the interactions that occur at leaf surfaces.“Billions of drops of pesticide are being sprayed on every acre of crop, and only a small fraction is ultimately reaching and staying on target. This seemed to me like a problem that we could help to solve,” he says.Varanasi and his students began exploring strategies to make drops of pesticide stick to leaves better, instead of bouncing off. They found that if they added polymers with positive and negative charges, the oppositely charged droplets would form a hydrophilic (water-attracting) coating on the leaf surface, which helps the next droplets applied to stick to the leaf.

    AgZen has developed a system for farming that can monitor exactly how much of the sprayed chemicals adheres to plants, in real time, as the sprayer drives through a field.

    Later, they developed an easier-to-use technology in which a surfactant is added to the pesticide before spraying. When this mixture is sprayed through a special nozzle, it forms tiny droplets that are “cloaked” in surfactant. The surfactant helps the droplets to stick to the leaves within a few milliseconds, without bouncing off.In 2020, Varanasi and Vishnu Jayaprakash SM ’19, PhD ’22 founded a company called AgZen to commercialize their technologies and get them into the hands of farmers. They incorporated their ideas for improving pesticide adhesion into a product called EnhanceCoverage.During the testing for this product, they realized that there weren’t any good ways to measure how many of the droplets were staying on the plant. That led them to develop a product known as RealCoverage, which is based on machine vision. It can be attached to any pesticide sprayer and offer real-time feedback on what percentage of the pesticide droplets are sticking to and staying on every leaf.RealCoverage was used on 65,000 acres of farmland across the United States in 2024, from soybeans in Iowa to cotton in Georgia. Farmers who used the product were able to reduce their pesticide use by 30 to 50 percent, by using the data to optimize delivery and, in some cases, even change what chemicals were sprayed.He hopes that the EnhanceCoverage product, which is expected to become available in 2025, will help farmers further reduce their pesticide use.“Our mission here is to help farmers with savings while helping them achieve better yields. We have found a way to do all this while also reducing waste and the amount of chemicals that we put into our atmosphere and into our soils and into our water,” Varanasi says. “This is the MIT approach: to figure out what are the real issues and how to come up with solutions. Now we have a tool and I hope that it’s deployed everywhere and everyone gets the benefit from it.” More

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    Aspiring to sustainable development

    In a first for both universities, MIT undergraduates are engaged in research projects at the Universidad del Valle de Guatemala (UVG), while MIT scholars are collaborating with UVG undergraduates on in-depth field studies in Guatemala.These pilot projects are part of a larger enterprise, called ASPIRE (Achieving Sustainable Partnerships for Innovation, Research, and Entrepreneurship). Funded by the U.S. Agency for International Development, this five-year, $15-million initiative brings together MIT, UVG, and the Guatemalan Exporters Association to promote sustainable solutions to local development challenges.“This research is yielding insights into our understanding of how to design with and for marginalized people, specifically Indigenous people,” says Elizabeth Hoffecker, co-principal investigator of ASPIRE at MIT and director of the MIT Local Innovation Group.The students’ work is bearing fruit in the form of publications and new products — directly advancing ASPIRE’s goals to create an innovation ecosystem in Guatemala that can be replicated elsewhere in Central and Latin America.For the students, the project offers rewards both tangible and inspirational.“My experience allowed me to find my interest in local innovation and entrepreneurship,” says Ximena Sarmiento García, a fifth-year undergraduate at UVG majoring in anthropology. Supervised by Hoffecker, Sarmiento García says, “I learned how to inform myself, investigate, and find solutions — to become a researcher.”Sandra Youssef, a rising junior in mechanical engineering at MIT, collaborated with UVG researchers and Indigenous farmers to design a mobile cart to improve the harvest yield of snow peas. “It was perfect for me,” she says. “My goal was to use creative, new technologies and science to make a dent in difficult problems.”Remote and effectiveKendra Leith, co-principal investigator of ASPIRE, and associate director for research at MIT D-Lab, shaped the MIT-based undergraduate research opportunities (UROPs) in concert with UVG colleagues. “Although MIT students aren’t currently permitted to travel to Guatemala, I wanted them to have an opportunity to apply their experience and knowledge to address real-world challenges,” says Leith. “The Covid pandemic prepared them and their counterparts at UVG for effective remote collaboration — the UROPs completed remarkably productive research projects over Zoom and met our goals for them.”MIT students participated in some of UVG’s most ambitious ASPIRE research. For instance, Sydney Baller, a rising sophomore in mechanical engineering, joined a team of Indigenous farmers and UVG mechanical engineers investigating the manufacturing process and potential markets for essential oils extracted from thyme, rosemary, and chamomile plants.“Indigenous people have thousands of years working with plant extracts and ancient remedies,” says Baller. “There is promising history there that would be important to follow up with more modern research.”Sandra Youssef used computer-aided design and manufacturing to realize a design created in a hackathon by snow pea farmers. “Our cart had to hold 495 pounds of snow peas without collapsing or overturning, navigate narrow paths on hills, and be simple and inexpensive to assemble,” she says. The snow pea producers have tested two of Youssef’s designs, built by a team at UVG led by Rony Herrarte, a faculty member in the department of mechanical engineering.From waste to filterTwo MIT undergraduates joined one of UVG’s long-standing projects: addressing pollution in Guatemala’s water. The research seeks to use chitosan molecules, extracted from shrimp shells, for bioremediation of heavy metals and other water contaminants. These shells are available in abundance, left as waste by the country’s shrimp industry.Sophomores Ariana Hodlewsky, majoring in chemical engineering, and Paolo Mangiafico, majoring in brain and cognitive sciences, signed on to work with principal investigator and chemistry department instructor Allan Vásquez (UVG) on filtration systems utilizing chitosan.“The team wants to find a cost-effective product rural communities, most at risk from polluted water, can use in homes or in town water systems,” says Mangiafico. “So we have been investigating different technologies for water filtration, and analyzing the Guatemalan and U.S. markets to understand the regulations and opportunities that might affect introduction of a chitosan-based product.”“Our research into how different communities use water and into potential consumers and pitfalls sets the scene for prototypes UVG wants to produce,” says Hodlewsky.Lourdes Figueroa, UVG ASPIRE project manager for technology transfer, found their assistance invaluable.“Paolo and Ariana brought the MIT culture and mindset to the project,” she says. “They wanted to understand not only how the technology works, but the best ways of getting the technology out of the lab to make it useful.”This was an “Aha!” moment, says Figueroa. “The MIT students made a major contribution to both the engineering and marketing sides by emphasizing that you have to think about how to guarantee the market acceptance of the technology while it is still under development.”Innovation ecosystemsUVG’s three campuses have served as incubators for problem-solving innovation and entrepreneurship, in many cases driven by students from Indigenous communities and families. In 2022, Elizabeth Hoffecker, with eight UVG anthropology majors, set out to identify the most vibrant examples of these collaborative initiatives, which ASPIRE seeks to promote and replicate.Hoffecker’s “innovation ecosystem diagnostic” revealed a cluster of activity centered on UVG’s Altiplano campus in the central highlands, which serves Mayan communities. Hoffecker and two of the anthropology students focused on four examples for a series of case studies, which they are currently preparing for submission to a peer-reviewed journal.“The caliber of their work was so good that it became clear to me that we could collaborate on a paper,” says Hoffecker. “It was my first time publishing with undergraduates.”The researchers’ cases included novel production of traditional thread, and creation of a 3D phytoplankton kit that is being used to educate community members about water pollution in Lake Atitlán, a tourist destination that drives the local economy but is increasingly being affected by toxic algae blooms. Hoffecker singles out a project by Indigenous undergraduates who developed play-based teaching tools for introducing basic mathematical concepts.“These connect to local Mayan ways of understanding and offer a novel, hands-on way to strengthen the math teaching skills of local primary school teachers in Indigenous communities,” says Hoffecker. “They created something that addresses a very immediate need in the community — lack of training.Both of Hoffecker’s undergraduate collaborators are writing theses inspired by these case studies.“My time with Elizabeth allowed me to learn how to conduct research from scratch, ask for help, find solutions, and trust myself,” says Sarmiento García. She finds the ASPIRE approach profoundly appealing. “It is not only ethical, but also deeply committed to applying results to the real lives of the people involved.”“This experience has been incredibly positive, validating my own ability to generate knowledge through research, rather than relying only on established authors to back up my arguments,” says Camila del Cid, a fifth-year anthropology student. “This was empowering, especially as a Latin American researcher, because it emphasized that my perspective and contributions are important.”Hoffecker says this pilot run with UVG undergrads produced “high-quality research that can inform evidence-based decision-making on development issues of top regional priority” — a key goal for ASPIRE. Hoffecker plans to “develop a pathway that other UVG students can follow to conduct similar research.”MIT undergraduate research will continue. “Our students’ activities have been very valuable in Guatemala, so much so that the snow pea, chitosan, and essential oils teams would like to continue working with our students this year,” says Leith.  She anticipates a new round of MIT UROPs for next summer.Youssef, for one, is eager to get to work on refining the snow pea cart. “I like the idea of working outside my comfort zone, thinking about things that seem unsolvable and coming up with a solution to fix some aspect of the problem,” she says. More

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    Study: Marshes provide cost-effective coastal protection

    Images of coastal houses being carried off into the sea due to eroding coastlines and powerful storm surges are becoming more commonplace as climate change brings a rising sea level coupled with more powerful storms. In the U.S. alone, coastal storms caused $165 billion in losses in 2022.Now, a study from MIT shows that protecting and enhancing salt marshes in front of protective seawalls can significantly help protect some coastlines, at a cost that makes this approach reasonable to implement.The new findings are being reported in the journal Communications Earth and Environment, in a paper by MIT graduate student Ernie I. H. Lee and professor of civil and environmental engineering Heidi Nepf. This study, Nepf says, shows that restoring coastal marshes “is not just something that would be nice to do, but it’s actually economically justifiable.” The researchers found that, among other things, the wave-attenuating effects of salt marsh mean that the seawall behind it can be built significantly lower, reducing construction cost while still providing as much protection from storms.“One of the other exciting things that the study really brings to light,” Nepf says, “is that you don’t need a huge marsh to get a good effect. It could be a relatively short marsh, just tens of meters wide, that can give you benefit.” That makes her hopeful, Nepf says, that this information might be applied in places where planners may have thought saving a smaller marsh was not worth the expense. “We show that it can make enough of a difference to be financially viable,” she says.While other studies have previously shown the benefits of natural marshes in attenuating damaging storms, Lee says that such studies “mainly focus on landscapes that have a wide marsh on the order of hundreds of meters. But we want to show that it also applies in urban settings where not as much marsh land is available, especially since in these places existing gray infrastructure (seawalls) tends to already be in place.”The study was based on computer modeling of waves propagating over different shore profiles, using the morphology of various salt marsh plants — the height and stiffness of the plants, and their spatial density — rather than an empirical drag coefficient. “It’s a physically based model of plant-wave interaction, which allowed us to look at the influence of plant species and changes in morphology across seasons,” without having to go out and calibrate the vegetation drag coefficient with field measurements for each different condition, Nepf says.The researchers based their benefit-cost analysis on a simple metric: To protect a certain length of shoreline, how much could the height of a given seawall be reduced if it were accompanied by a given amount of marsh? Other ways of assessing the value, such as including the value of real estate that might be damaged by a given amount of flooding, “vary a lot depending on how you value the assets if a flood happens,” Lee says. “We use a more concrete value to quantify the benefits of salt marshes, which is the equivalent height of seawall you would need to deliver the same protection value.”They used models of a variety of plants, reflecting differences in height and the stiffness across different seasons. They found a twofold variation in the various plants’ effectiveness in attenuating waves, but all provided a useful benefit.To demonstrate the details in a real-world example and help to validate the simulations, Nepf and Lee studied local salt marshes in Salem, Massachusetts, where projects are already underway to try to restore marshes that had been degraded. Including the specific example provided a template for others, Nepf says. In Salem, their model showed that a healthy salt marsh could offset the need for an additional seawall height of 1.7 meters (about 5.5 feet), based on satisfying a rate of wave overtopping that was set for the safety of pedestrians.However, the real-world data needed to model a marsh, including maps of salt marsh species, plant height, and shoots per bed area, are “very labor-intensive” to put together, Nepf says. Lee is now developing a method to use drone imaging and machine learning to facilitate this mapmaking. Nepf says this will enable researchers or planners to evaluate a given area of marshland and say, “How much is this marsh worth in terms of its ability to reduce flooding?”The White House Office of Information and Regulatory Affairs recently released guidance for assessing the value of ecosystem services in planning of federal projects, Nepf explains.  “But in many scenarios, it lacks specific methods for quantifying value, and this study is meeting that need,” she says.The Federal Emergency Management Agency also has a benefit-cost analysis (BCA) toolkit, Lee notes. “They have guidelines on how to quantify each of the environmental services, and one of the novelties of this paper is quantifying the cost and the protection value of marshes. This is one of the applications that policymakers can consider on how to quantify the environmental service values of marshes,” he says.The software that environmental engineers can apply to specific sites has been made available online for free on GitHub. “It’s a one-dimensional model accessible by a standard consulting firm,” Nepf says.“This paper presents a practical tool for translating the wave attenuation capabilities of marshes into economic values, which could assist decision-makers in the adaptation of marshes for nature-based coastal defense,” says Xioaxia Zhang, a professor at Shenzen University in China who was not involved in this work. “The results indicate that salt marshes are not only environmentally beneficial but also cost-effective.”The study “is a very important and crucial step to quantifying the protective value of marshes,” adds Bas Borsje, an associate professor of nature-based flood protection at the University of Twente in the Netherlands, who was not associated with this work. “The most important step missing at the moment is how to translate our findings to the decision makers. This is the first time I’m aware of that decision-makers are quantitatively informed on the protection value of salt marshes.”Lee received support for this work from the Schoettler Scholarship Fund, administered by the MIT Department of Civil and Environmental Engineering. More

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    Uplifting West African communities, one cashew at a time

    Ever wonder how your favorite snack was sourced? Joshua Reed-Diawuoh thinks more people should.Reed-Diawuoh MBA ’20 is the founder and CEO of GRIA Food Company, which partners with companies that ethically source and process food in West Africa to support local food economies and help communities in the region more broadly.“It’s very difficult for these agribusinesses and producers to start sustainable businesses and build up that value chain in the area,” says Reed-Diawuoh, who started the company as a student in the MIT Sloan School of Management. “We want to support these companies that put in the work to build integrated businesses that are employing people and uplifting communities.”GRIA, which stands for “Grown in Africa,” is currently selling six types of flavored cashews sourced from Benin, Togo, and Burkina Faso. All of the cashews are certified by Fairtrade International, which means in addition to offering sustainable wages, access to financing, and decent working conditions, the companies receive a “Fairtrade Premium” on top of the selling price that allows them to invest in the long-term health of their communities.“That premium is transformational,” Reed-Diawuoh says. “The premium goes to the producer cooperatives, or the farmers working the land, and they can invest that in any way they choose. They can put it back into their business, they can start new community development projects, like building schools or improving wastewater infrastructure, whatever they want.”Cracking the nutReed-Diawuoh’s family is from Ghana, and before coming to MIT Sloan, he worked to support agriculture and food manufacturing for countries in Sub-Saharan Africa, with particular focus on uplifting small-scale farmers. That’s where he learned about difficulties with financing and infrastructure constraints that held many companies back.“I wanted to get my hands dirty and start my own business that contributed to improving agricultural development in West Africa,” Reed-Diawuoh says.He entered MIT Sloan in 2018, taking entrepreneurship classes and exploring several business ideas before deciding to ethically source produce from farmers and sell directly to consumers. He says MIT Sloan’s Sustainability Business Lab offered particularly valuable lessons for how to structure his business.In his second year, Reed-Diawuoh was selected for a fellowship at the Legatum Center, which connected him to other entrepreneurs working in emerging markets around the world.“Legatum was a pivotal milestone for me,” he says. “It provided me with some structure and space to develop this idea. It also gave me an incredible opportunity to take risks and explore different business concepts in a way I couldn’t have done if I was working in industry.”The business model Reed-Diawuoh settled on for GRIA sources product from agribusiness partners in West Africa that adhere to the strictest environmental and labor standards. Reed-Diawuoh decided to start with cashews because they have many manual processing steps — from shelling to peeling and roasting — that are often done after the cashews are shipped out of West Africa, limiting the growth of local food economies and taking wealth out of communities.Each of GRIA’s partners, from the companies harvesting cashews to the processing facilities, works directly with farmer cooperatives and small-scale farmers and is certified by Fairtrade International.“Without proper oversight and regulations, workers oftentimes get exploited, and child labor is a huge problem across the agriculture sector,” Reed-Diawuoh says. “Fairtrade certifications try and take a robust and rigorous approach to auditing all of the businesses and their supply chains, from producers to farmers to processors. They do on-site visits and they audit financial documents. We went through this over the course of a thorough three-month review.”After importing cashew kernels, GRIA flavors and packages them at a production facility in Boston. Reed-Diawuoh started by selling to small independent retailers in Greater Boston before scaling up GRIA’s online sales. He started ramping up production in the beginning of 2023.“Every time we sell our product, if people weren’t already familiar with Fairtrade or ethical sourcing, we provide information on our packaging and all of our collateral,” Reed-Diawuoh says. “We want to spread this message about the importance of ethical sourcing and the importance of building up food manufacturing in West Africa in particular, but also in rising economies throughout the world.”Making ethical sourcing mainstreamGRIA currently imports about a ton of Fairtrade cashews and kernels each quarter, and Reed-Diawuoh hopes to double that number each year for the foreseeable future.“For each pound, we pay premiums for the kernels, and that supports this ecosystem where producers get compensated fairly for their work on the land, and agribusinesses are able to build more robust and profitable business models, because they have an end market for these Fairtrade-certified products.”Reed-Diawuoh is currently trying out different packaging and flavors and is in discussions with partners to expand production capacity and move into Ghana. He’s also exploring corporate collaborations and has provided MIT with product over the past two years for conferences and other events.“We’re experimenting with different growth strategies,” Reed-Diawuoh says. “We’re very much still in startup mode, but really trying to ramp up our sales and production.”As GRIA scales, Reed-Diawuoh hopes it pushes consumers to start asking more of their favorite food brands.“It’s absolutely critical that, if we’re sourcing produce in markets like the U.S. from places like West Africa, we’re hyper-focused on doing it in an ethical manner,” Reed-Diawuoh says. “The overall goal of GRIA is to ensure we are adhering to and promoting strict sourcing standards and being rigorous and thoughtful about the way we import product.” More

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    MIT Energy and Climate Club mobilizes future leaders to address global climate issues

    One of MIT’s missions is helping to solve the world’s greatest problems — with a large focus on one of the most pressing topics facing the world today, climate change.The MIT Energy and Climate Club, (MITEC) formerly known as the MIT Energy Club, has been working since 2004 to inform and educate the entire MIT community about this urgent issue and other related matters.MITEC, one of the largest clubs on campus, has hundreds of active members from every major, including both undergraduate and graduate students. With a broad reach across the Institute, MITEC is the hub for thought leadership and relationship-building across campus.The club’s co-presidents Laurențiu Anton, doctoral candidate in electrical engineering and computer science; Rosie Keller, an MBA student in the MIT Sloan School of Management; and Thomas Lee, doctoral candidate in the Institute for Data, Systems, and Society, say that faculty, staff, and alumni are also welcome to join and interact with the continuously growing club.While they closely collaborate on all aspects of the club, each of the co-presidents has a focus area to support the student managing directors and vice presidents for several of the club’s committees. Keller oversees the External Relations, Social, Launchpad, and Energy and Climate Hackathon leadership teams. Lee supports the leadership team for next spring’s Energy Conference. He also assists the club treasurer on budget and finance and guides the industry Sponsorships team. Anton oversees marketing, community and education as well as the Energy and Climate Night and Energy and Climate Career Fair leadership teams.“We think of MITEC as the umbrella of all things related to energy and climate on campus. Our goal is to share actionable information and not just have discussions. We work with other organizations on campus, including the MIT Environmental Solutions Initiative, to bring awareness,” says Anton. “Our Community and Education team is currently working with the MIT ESI [Environmental Solutions Initiative] to create an ecosystem map that we’re excited to produce for the MIT community.”To share their knowledge and get more people interested in solving climate and energy problems, each year MITEC hosts a variety of events including the MIT Energy and Climate Night, the MIT Energy and Climate Hack, the MIT Energy and Climate Career Fair, and the MIT Energy Conference to be held next spring March 3-4. The club also offers students the opportunity to gain valuable work experience while engaging with top companies, such as Constellation Energy and GE Vernova, on real climate and energy issues through their Launchpad Program.Founded in 2006, the annual MIT Energy Conference is the largest student-run conference in North America focused on energy and climate issues, where hundreds of participants gather every year with the CEOs, policymakers, investors, and scholars at the forefront of the global energy transition.“The 2025 MIT Energy Conference’s theme is ‘Breakthrough to Deployment: Driving Climate Innovation to Market’ — which focuses on the importance of both cutting-edge research innovation as well as large-scale commercial deployment to successfully reach climate goals,” says Lee.Anton notes that the first of four MITEC flagship events the MIT Energy and Climate Night. This research symposium that takes place every year in the fall at the MIT Museum will be held on Nov. 8. The club invites a select number of keynote speakers and several dozen student posters. Guests are allowed to walk around and engage with students, and in return students get practice showcasing their research. The club’s career fair will take place in the spring semester, shortly after Independent Activities Period.MITEC also provides members opportunities to meet with companies that are working to improve the energy sector, which helps to slow down, as well as adapt to, the effects of climate change.“We recently went to Provincetown and toured Eversource’s battery energy storage facility. This helped open doors for club members,” says Keller. “The Provincetown battery helps address grid reliability problems after extreme storms on Cape Cod — which speaks to energy’s connection to both the mitigation and adaptation aspects of climate change,” adds Lee.“MITEC is also a great way to meet other students at MIT that you might not otherwise have a chance to,” says Keller.“We’d always welcome more undergraduate students to join MITEC. There are lots of leadership opportunities within the club for them to take advantage of and build their resumes. We also have good and growing collaboration between different centers on campus such as the Sloan Sustainability Initiative and the MIT Energy Initiative. They support us with resources, introductions, and help amplify what we’re doing. But students are the drivers of the club and set the agendas,” says Lee.All three co-presidents are excited to hear that MIT President Sally Kornbluth wants to bring climate change solutions to the next level, and that she recently launched The Climate Project at MIT to kick off the Institute’s major new effort to accelerate and scale up climate change solutions.“We look forward to connecting with the new directors of the Climate Project at MIT and Interim Vice President for Climate Change Richard Lester in the near future. We are eager to explore how MITEC can support and collaborate with the Climate Project at MIT,” says Anton.Lee, Keller, and Anton want MITEC to continue fostering solutions to climate issues. They emphasized that while individual actions like bringing your own thermos, using public transportation, or recycling are necessary, there’s a bigger picture to consider. They encourage the MIT community to think critically about the infrastructure and extensive supply chains behind the products everyone uses daily.“It’s not just about bringing a thermos; it’s also understanding the life cycle of that thermos, from production to disposal, and how our everyday choices are interconnected with global climate impacts,” says Anton.“Everyone should get involved with this worldwide problem. We’d like to see more people think about how they can use their careers for change. To think how they can navigate the type of role they can play — whether it’s in finance or on the technical side. I think exploring what that looks like as a career is also a really interesting way of thinking about how to get involved with the problem,” says Keller.“MITEC’s newsletter reaches more than 4,000 people. We’re grateful that so many people are interested in energy and climate change,” says Anton. More

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    Study finds mercury pollution from human activities is declining

    MIT researchers have some good environmental news: Mercury emissions from human activity have been declining over the past two decades, despite global emissions inventories that indicate otherwise.In a new study, the researchers analyzed measurements from all available monitoring stations in the Northern Hemisphere and found that atmospheric concentrations of mercury declined by about 10 percent between 2005 and 2020.They used two separate modeling methods to determine what is driving that trend. Both techniques pointed to a decline in mercury emissions from human activity as the most likely cause.Global inventories, on the other hand, have reported opposite trends. These inventories estimate atmospheric emissions using models that incorporate average emission rates of polluting activities and the scale of these activities worldwide.“Our work shows that it is very important to learn from actual, on-the-ground data to try and improve our models and these emissions estimates. This is very relevant for policy because, if we are not able to accurately estimate past mercury emissions, how are we going to predict how mercury pollution will evolve in the future?” says Ari Feinberg, a former postdoc in the Institute for Data, Systems, and Society (IDSS) and lead author of the study.The new results could help inform scientists who are embarking on a collaborative, global effort to evaluate pollution models and develop a more in-depth understanding of what drives global atmospheric concentrations of mercury.However, due to a lack of data from global monitoring stations and limitations in the scientific understanding of mercury pollution, the researchers couldn’t pinpoint a definitive reason for the mismatch between the inventories and the recorded measurements.“It seems like mercury emissions are moving in the right direction, and could continue to do so, which is heartening to see. But this was as far as we could get with mercury. We need to keep measuring and advancing the science,” adds co-author Noelle Selin, an MIT professor in the IDSS and the Department of Earth, Atmospheric and Planetary Sciences (EAPS).Feinberg and Selin, his MIT postdoctoral advisor, are joined on the paper by an international team of researchers that contributed atmospheric mercury measurement data and statistical methods to the study. The research appears this week in the Proceedings of the National Academy of Sciences.Mercury mismatchThe Minamata Convention is a global treaty that aims to cut human-caused emissions of mercury, a potent neurotoxin that enters the atmosphere from sources like coal-fired power plants and small-scale gold mining.The treaty, which was signed in 2013 and went into force in 2017, is evaluated every five years. The first meeting of its conference of parties coincided with disheartening news reports that said global inventories of mercury emissions, compiled in part from information from national inventories, had increased despite international efforts to reduce them.This was puzzling news for environmental scientists like Selin. Data from monitoring stations showed atmospheric mercury concentrations declining during the same period.Bottom-up inventories combine emission factors, such as the amount of mercury that enters the atmosphere when coal mined in a certain region is burned, with estimates of pollution-causing activities, like how much of that coal is burned in power plants.“The big question we wanted to answer was: What is actually happening to mercury in the atmosphere and what does that say about anthropogenic emissions over time?” Selin says.Modeling mercury emissions is especially tricky. First, mercury is the only metal that is in liquid form at room temperature, so it has unique properties. Moreover, mercury that has been removed from the atmosphere by sinks like the ocean or land can be re-emitted later, making it hard to identify primary emission sources.At the same time, mercury is more difficult to study in laboratory settings than many other air pollutants, especially due to its toxicity, so scientists have limited understanding of all chemical reactions mercury can undergo. There is also a much smaller network of mercury monitoring stations, compared to other polluting gases like methane and nitrous oxide.“One of the challenges of our study was to come up with statistical methods that can address those data gaps, because available measurements come from different time periods and different measurement networks,” Feinberg says.Multifaceted modelsThe researchers compiled data from 51 stations in the Northern Hemisphere. They used statistical techniques to aggregate data from nearby stations, which helped them overcome data gaps and evaluate regional trends.By combining data from 11 regions, their analysis indicated that Northern Hemisphere atmospheric mercury concentrations declined by about 10 percent between 2005 and 2020.Then the researchers used two modeling methods — biogeochemical box modeling and chemical transport modeling — to explore possible causes of that decline.  Box modeling was used to run hundreds of thousands of simulations to evaluate a wide array of emission scenarios. Chemical transport modeling is more computationally expensive but enables researchers to assess the impacts of meteorology and spatial variations on trends in selected scenarios.For instance, they tested one hypothesis that there may be an additional environmental sink that is removing more mercury from the atmosphere than previously thought. The models would indicate the feasibility of an unknown sink of that magnitude.“As we went through each hypothesis systematically, we were pretty surprised that we could really point to declines in anthropogenic emissions as being the most likely cause,” Selin says.Their work underscores the importance of long-term mercury monitoring stations, Feinberg adds. Many stations the researchers evaluated are no longer operational because of a lack of funding.While their analysis couldn’t zero in on exactly why the emissions inventories didn’t match up with actual data, they have a few hypotheses.One possibility is that global inventories are missing key information from certain countries. For instance, the researchers resolved some discrepancies when they used a more detailed regional inventory from China. But there was still a gap between observations and estimates.They also suspect the discrepancy might be the result of changes in two large sources of mercury that are particularly uncertain: emissions from small-scale gold mining and mercury-containing products.Small-scale gold mining involves using mercury to extract gold from soil and is often performed in remote parts of developing countries, making it hard to estimate. Yet small-scale gold mining contributes about 40 percent of human-made emissions.In addition, it’s difficult to determine how long it takes the pollutant to be released into the atmosphere from discarded products like thermometers or scientific equipment.“We’re not there yet where we can really pinpoint which source is responsible for this discrepancy,” Feinberg says.In the future, researchers from multiple countries, including MIT, will collaborate to study and improve the models they use to estimate and evaluate emissions. This research will be influential in helping that project move the needle on monitoring mercury, he says.This research was funded by the Swiss National Science Foundation, the U.S. National Science Foundation, and the U.S. Environmental Protection Agency. More