Profile

Subterms

    More stories

    • 75 Shares149 Views

      in Environment

      Exploring the bow shock and beyond

      by

      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

    • 50 Shares109 Views

      in Environment

      Engineering for social impact

      by

      A desire to make meaningful contributions to society has influenced Runako Gentles’ path in life. Gentles grew up in Jamaica with a supportive extended family that instilled in him his connection to his faith and his aspiration to aim for greatness.

      “While growing up, I was encouraged to live a life that could potentially bring about major positive changes in my family and many other people’s lives,” says the MIT junior.

      One of those pathways his parents encouraged is pursuing excellence in academics.

      Gentles attended Campion College, a Jesuit high school in Jamaica for academically high-achieving students. Gentles was valedictorian and even won an award “for the member of the valedictory class who most closely resembles the ideal of intellectual competence, openness to growth, and commitment to social justice.”

      Although he did well in all subjects, he naturally gravitated toward biology and chemistry. “There are certain subjects people just make sense of material much faster, and high school biology and chemistry were those subjects for me,” he says. His love of learning often surprised friends and classmates when he could recall science concepts and definitions years later.  

      For several years Gentles wanted to pursue the field of medicine. He remembers becoming more excited about the career of a surgeon after reading a book on the story of retired neurosurgeon Ben Carson. During his advanced studies at Campion, he attended a career event and met with a neurosurgeon who invited him and other classmates to watch a surgical procedure. Gentles had the unique learning experience to observe a spinal operation. Around that same time another learning opportunity presented itself. His biology teacher recommended he apply to a Caribbean Science Foundation initiative called Student Program for Innovation, Science, and Engineering (SPISE) to explore careers in science, technology, engineering, and math. The intensive residential summer program for Caribbean students is modeled after the Minority Introduction to Engineering and Science (MITES) program at MIT. Cardinal Warde, a professor of electrical engineering at MIT who is also from the Caribbean, serves as the faculty director for both MITES and SPISE. The program was Gentles’ first major exposure to engineering.

      “I felt like I was in my first year of college at SPISE. It was an amazing experience and it helped me realize the opportunities that an engineering career path offers,” Gentles says. He excelled in the SPISE program, even winning one of the program’s highest honors for demonstrating overall excellence and leadership.

      SPISE was profoundly impactful to Gentles and he decided to pursue engineering at MIT. While further exploring his engineering interests before his first year at MIT, he remembers reading an article that piqued his interest in industry sectors that met basic human and societal needs.

      “I started thinking more about engineering and ethics,” says Gentles. He wanted to spend his time learning how to use science and engineering to make meaningful change in society.  “I think back to wanting to be a doctor for many years to help sick people, but I took it a step further. I wanted to get closer to addressing some of the root causes of deaths, illnesses, and the poor quality of life for billions of people,” he says of his decision to pursue a degree in civil and environmental engineering.

      Gentles spent his first semester at MIT working as a remote student when the Covid pandemic shut down in-person learning. He participated in 1.097 (Introduction to Civil and Environmental Engineering Research) during the January Independent Activities Period, in which undergraduates work one-on-one with graduate students or postdoc mentors on research projects that align with their interests. Gentles worked in the lab of Ruben Juanes exploring the use of machine learning to analyze earthquake data to determine whether different geologic faults in Puerto Rico resulted in distinguishable earthquake clusters. He joined the lab of Desiree Plata in the summer of his sophomore year on another undergraduate research opportunity (UROP) project, analyzing diesel range organic compounds in water samples collected from shallow groundwater sources near hydraulic fracking sites in West Virginia. The experience even led Gentles to be a co-author in his graduate student mentor’s abstract proposal for the American Geophysical Union Fall Meeting 2022 conference.  

      Gentles says he found the Department of Civil and Environmental Engineering a place for him to have the big-picture mindset of thinking about how technology is going to affect the environment, which ultimately affects society. “Choosing this department was not just about gaining the technical knowledge that most interested me. I wanted to be in a space where I would significantly develop my mindset of using innovation to bring more harmony between society and the environment,” says Gentles.

      Outside of the classroom, learning acoustic guitar is a passion for Gentles. He plays at social events for Cru, a Christian community at MIT, where he serves as a team leader. He credits Cru with helping him feel connected to a lot of different people, even outside of MIT.

      He’s also a member of the Bernard M. Gordon-MIT Engineering Leadership Program, which helps undergraduates gain and hone leadership skills to prepare them for careers in engineering. After learning and exploring more UROPs and classes in civil and environmental engineering, he aspires to hold a position of leadership where he can use his environmental knowledge to impact human lives.

      “Mitigating environmental issues can sometimes be a very complicated endeavor involving many stakeholders,” Gentles says. “We need more bright minds to be thinking of creative ways to address these pressing problems. We need more leaders helping to make society more harmonious with our planet.” More

    • 138 Shares199 Views

      in Energy

      An interdisciplinary approach to fighting climate change through clean energy solutions

      by

      In early 2021, the U.S. government set an ambitious goal: to decarbonize its power grid, the system that generates and transmits electricity throughout the country, by 2035. It’s an important goal in the fight against climate change, and will require a switch from current, greenhouse-gas producing energy sources (such as coal and natural gas), to predominantly renewable ones (such as wind and solar).

      Getting the power grid to zero carbon will be a challenging undertaking, as Audun Botterud, a principal research scientist at the MIT Laboratory for Information and Decision Systems (LIDS) who has long been interested in the problem, knows well. It will require building lots of renewable energy generators and new infrastructure; designing better technology to capture, store, and carry electricity; creating the right regulatory and economic incentives; and more. Decarbonizing the grid also presents many computational challenges, which is where Botterud’s focus lies. Botterud has modeled different aspects of the grid — the mechanics of energy supply, demand, and storage, and electricity markets — where economic factors can have a huge effect on how quickly renewable solutions get adopted.

      On again, off again

      A major challenge of decarbonization is that the grid must be designed and operated to reliably meet demand. Using renewable energy sources complicates this, as wind and solar power depend on an infamously volatile system: the weather. A sunny day becomes gray and blustery, and wind turbines get a boost but solar farms go idle. This will make the grid’s energy supply variable and hard to predict. Additional resources, including batteries and backup power generators, will need to be incorporated to regulate supply. Extreme weather events, which are becoming more common with climate change, can further strain both supply and demand. Managing a renewables-driven grid will require algorithms that can minimize uncertainty in the face of constant, sometimes random fluctuations to make better predictions of supply and demand, guide how resources are added to the grid, and inform how those resources are committed and dispatched across the entire United States.

      “The problem of managing supply and demand in the grid has to happen every second throughout the year, and given how much we rely on electricity in society, we need to get this right,” Botterud says. “You cannot let the reliability drop as you increase the amount of renewables, especially because I think that will lead to resistance towards adopting renewables.”

      That is why Botterud feels fortunate to be working on the decarbonization problem at LIDS — even though a career here is not something he had originally planned. Botterud’s first experience with MIT came during his time as a graduate student in his home country of Norway, when he spent a year as a visiting student with what is now called the MIT Energy Initiative. He might never have returned, except that while at MIT, Botterud met his future wife, Bilge Yildiz. The pair both ended up working at the Argonne National Laboratory outside of Chicago, with Botterud focusing on challenges related to power systems and electricity markets. Then Yildiz got a faculty position at MIT, where she is a professor of nuclear and materials science and engineering. Botterud moved back to the Cambridge area with her and continued to work for Argonne remotely, but he also kept an eye on local opportunities. Eventually, a position at LIDS became available, and Botterud took it, while maintaining his connections to Argonne.

      “At first glance, it may not be an obvious fit,” Botterud says. “My work is very focused on a specific application, power system challenges, and LIDS tends to be more focused on fundamental methods to use across many different application areas. However, being at LIDS, my lab [the Energy Analytics Group] has access to the most recent advances in these fundamental methods, and we can apply them to power and energy problems. Other people at LIDS are working on energy too, so there is growing momentum to address these important problems.”

      Weather, space, and time

      Much of Botterud’s research involves optimization, using mathematical programming to compare alternatives and find the best solution. Common computational challenges include dealing with large geographical areas that contain regions with different weather, different types and quantities of renewable energy available, and different infrastructure and consumer needs — such as the entire United States. Another challenge is the need for granular time resolution, sometimes even down to the sub-second level, to account for changes in energy supply and demand.

      Often, Botterud’s group will use decomposition to solve such large problems piecemeal and then stitch together solutions. However, it’s also important to consider systems as a whole. For example, in a recent paper, Botterud’s lab looked at the effect of building new transmission lines as part of national decarbonization. They modeled solutions assuming coordination at the state, regional, or national level, and found that the more regions coordinate to build transmission infrastructure and distribute electricity, the less they will need to spend to reach zero carbon.

      In other projects, Botterud uses game theory approaches to study strategic interactions in electricity markets. For example, he has designed agent-based models to analyze electricity markets. These assume each actor will make strategic decisions in their own best interest and then simulate interactions between them. Interested parties can use the models to see what would happen under different conditions and market rules, which may lead companies to make different investment decisions, or governing bodies to issue different regulations and incentives. These choices can shape how quickly the grid gets decarbonized.

      Botterud is also collaborating with researchers in MIT’s chemical engineering department who are working on improving battery storage technologies. Batteries will help manage variable renewable energy supply by capturing surplus energy during periods of high generation to release during periods of insufficient generation. Botterud’s group models the sort of charge cycles that batteries are likely to experience in the power grid, so that chemical engineers in the lab can test their batteries’ abilities in more realistic scenarios. In turn, this also leads to a more realistic representation of batteries in power system optimization models.

      These are only some of the problems that Botterud works on. He enjoys the challenge of tackling a spectrum of different projects, collaborating with everyone from engineers to architects to economists. He also believes that such collaboration leads to better solutions. The problems created by climate change are myriad and complex, and solving them will require researchers to cooperate and explore.

      “In order to have a real impact on interdisciplinary problems like energy and climate,” Botterud says, “you need to get outside of your research sweet spot and broaden your approach.” More

    • 88 Shares189 Views

      in Energy

      Michael Howland gives wind energy a lift

      by

      Michael Howland was in his office at MIT, watching real-time data from a wind farm 7,000 miles away in northwest India, when he noticed something odd: Some of the turbines weren’t producing the expected amount of electricity.

      Howland, the Esther and Harold E. Edgerton Assistant Professor of Civil and Environmental Engineering, studies the physics of the Earth’s atmosphere and how that information can optimize renewable energy systems. To accomplish this, he and his team develop and use predictive models, supercomputer simulations, and real-life data from wind farms, such as the one in India.

      The global wind power market is one of the most cost-competitive and resilient power sources across the world, the Global Wind Energy Council reported last year. The year 2020 saw record growth in wind power capacity, thanks to a surge of installations in China and the United States. Yet wind power needs to grow three times faster in the coming decade to address the worst impacts of climate change and achieve federal and state climate goals, the report says.

      “Optimal wind farm design and the resulting cost of energy are dependent on the wind,” Howland says. “But wind farms are often sited and designed based on short-term historical climate records.”

      In October 2021, Howland received a Seed Fund grant from the MIT Energy Initiative (MITEI) to account for how climate change might affect the wind of the future. “Our initial results suggest that considering the uncertainty in the winds in the design and operation of wind farms can lead to more reliable energy production,” he says.

      Most recently, Howland and his team came up with a model that predicts the power produced by each individual turbine based on the physics of the wind farm as a whole. The model can inform decisions that may boost a farm’s overall output.

      The state of the planet

      Growing up in a suburb of Philadelphia, the son of neuroscientists, Howland’s childhood wasn’t especially outdoorsy. Later, he’d become an avid hiker with a deep appreciation for nature, but a ninth-grade class assignment made him think about the state of the planet, perhaps for the first time.

      A history teacher had asked the class to write a report on climate change. “I remember arguing with my high school classmates about whether humans were the leading cause of climate change, but the teacher didn’t want to get into that debate,” Howland recalls. “He said climate change was happening, whether or not you accept that it’s anthropogenic, and he wanted us to think about the impacts of global warming, and solutions. I was one of his vigorous defenders.”

      As part of a research internship after his first year of college, Howland visited a wind farm in Iowa, where wind produces more than half of the state’s electricity. “The turbines look tall from the highway, but when you’re underneath them, you’re really struck by their scale,” he says. “That’s where you get a sense of how colossal they really are.” (Not a fan of heights, Howland opted not to climb the turbine’s internal ladder to snap a photo from the top.)

      After receiving an undergraduate degree from Johns Hopkins University and master’s and PhD degrees in mechanical engineering from Stanford University, he joined MIT’s Department of Civil and Environmental Engineering to focus on the intersection of fluid mechanics, weather, climate, and energy modeling. His goal is to enhance renewable energy systems.

      An added bonus to being at MIT is the opportunity to inspire the next generation, much like his ninth-grade history teacher did for him. Howland’s graduate-level introduction to the atmospheric boundary layer is geared primarily to engineers and physicists, but as he sees it, climate change is such a multidisciplinary and complex challenge that “every skill set that exists in human society can be relevant to mitigating it.”

      “There are the physics and engineering questions that our lab primarily works on, but there are also questions related to social sciences, public acceptance, policymaking, and implementation,” he says. “Careers in renewable energy are rapidly growing. There are far more job openings than we can hire for right now. In many areas, we don’t yet have enough people to address the challenges in renewable energy and climate change mitigation that need to be solved.

      “I encourage my students — really, everyone I interact with — to find a way to impact the climate change problem,” he says.

      Unusual conditions

      In fall 2021, Howland was trying to explain the odd data coming in from India.

      Based on sensor feedback, wind turbines’ software-driven control systems constantly tweak the speed and the angle of the blades, and what’s known as yaw — the orientation of the giant blades in relation to the wind direction.

      Existing utility-scale turbines are controlled “greedily,” which means that every turbine in the farm automatically turns into the wind to maximize its own power production.

      Though the turbines in the front row of the Indian wind farm were reacting appropriately to the wind direction, their power output was all over the place. “Not what we would expect based on the existing models,” Howland says.

      These massive turbine towers stood at 100 meters, about the length of a football field, with blades the length of an Olympic swimming pool. At their highest point, the blade tips lunged almost 200 meters into the sky.

      Then there’s the speed of the blades themselves: The tips move many times faster than the wind, around 80 to 100 meters per second — up to a quarter or a third of the speed of sound.

      Using a state-of-the-art sensor that measures the speed of incoming wind before it interacts with the massive rotors, Howland’s team saw an unexpectedly complex airflow effect. He covers the phenomenon in his class. The data coming in from India, he says, displayed “quite remarkable wind conditions stemming from the effects of Earth’s rotation and the physics of buoyancy 
that you don’t always see.”

      Traditionally, wind turbines operate in the lowest 10 percent of the atmospheric boundary layer — the so-called surface layer — which is affected primarily by ground conditions. The Indian turbines, Howland realized, were operating in regions of the atmosphere that turbines haven’t historically accessed.

      Trending taller

      Howland knew that airflow interactions can persist for kilometers. The interaction of high winds with the front-row turbines was generating wakes in the air similar to the way boats generate wakes in the water.

      To address this, Howland’s model trades off the efficiency of upwind turbines to benefit downwind ones. By misaligning some of the upwind turbines in certain conditions, the downwind units experience less wake turbulence, increasing the overall energy output of the wind farm by as much as 1 percent to 3 percent, without requiring additional costs. If a 1.2 percent energy increase was applied to the world’s existing wind farms, it would be the equivalent of adding more than 3,600 new wind turbines — enough to power about 3 million homes.

      Even a modest boost could mean fewer turbines generating the same output, or the ability to place more units into a smaller space, because negative interactions between the turbines can be diminished.

      Howland says the model can predict potential benefits in a variety of scenarios at different types of wind farms. “The part that’s important and exciting is that it’s not just particular to this wind farm. We can apply the collective control method across the wind farm fleet,” he says, which is growing taller and wider.

      By 2035, the average hub height for offshore turbines in the United States is projected to grow from 100 meters to around 150 meters — the height of the Washington Monument.

      “As we continue to build larger wind turbines and larger wind farms, we need to revisit the existing practice for their design and control,” Howland says. “We can use our predictive models to ensure that we build and operate the most efficient renewable generators possible.”

      Looking to the future

      Howland and other climate watchers have reason for optimism with the passage in August 2022 of the Inflation Reduction Act, which calls for a significant investment in domestic energy production and for reducing carbon emissions by roughly 40 percent by 2030.

      But Howland says the act itself isn’t sufficient. “We need to continue pushing the envelope in research and development as well as deployment,” he says. The model he created with his team can help, especially for offshore wind farms experiencing low wind turbulence and larger wake interactions.

      Offshore wind can face challenges of public acceptance. Howland believes that researchers, policymakers, and the energy industry need to do more to get the public on board by addressing concerns through open public dialogue, outreach, and education.

      Howland once wrote and illustrated a children’s book, inspired by Dr. Seuss’s “The Lorax,” that focused on renewable energy. Howland recalls his “really terrible illustrations,” but he believes he was onto something. “I was having some fun helping people interact with alternative energy in a more natural way at an earlier age,” he says, “and recognize that these are not nefarious technologies, but remarkable feats of human ingenuity.” More

    • 75 Shares169 Views

      in Energy

      Helping the cause of environmental resilience

      by

      Haruko Wainwright, the Norman C. Rasmussen Career Development Professor in Nuclear Science and Engineering (NSE) and assistant professor in civil and environmental engineering at MIT, grew up in rural Japan, where many nuclear facilities are located. She remembers worrying about the facilities as a child. Wainwright was only 6 at the time of the Chernobyl accident in 1986, but still recollects it vividly.

      Those early memories have contributed to Wainwright’s determination to research how technologies can mold environmental resilience — the capability of mitigating the consequences of accidents and recovering from contamination.

      Wainwright believes that environmental monitoring can help improve resilience. She co-leads the U.S. Department of Energy (DOE)’s Advanced Long-term Environmental Monitoring Systems (ALTEMIS) project, which integrates technologies such as in situ sensors, geophysics, remote sensing, simulations, and artificial intelligence to establish new paradigms for monitoring. The project focuses on soil and groundwater contamination at more than 100 U.S. sites that were used for nuclear weapons production.

      As part of this research, which was featured last year in Environmental Science & Technology Journal, Wainwright is working on a machine learning framework for improving environmental monitoring strategies. She hopes the ALTEMIS project will enable the rapid detection of anomalies while ensuring the stability of residual contamination and waste disposal facilities.

      Childhood in rural Japan

      Even as a child, Wainwright was interested in physics, history, and a variety of other subjects.

      But growing up in a rural area was not ideal for someone interested in STEM. There were no engineers or scientists in the community and no science museums, either. “It was not so cool to be interested in science, and I never talked about my interest with anyone,” Wainwright recalls.

      Television and books were the only door to the world of science. “I did not study English until middle school and I had never been on a plane until college. I sometimes find it miraculous that I am now working in the U.S. and teaching at MIT,” she says.

      As she grew a little older, Wainwright heard a lot of discussions about nuclear facilities in the region and many stories about Hiroshima and Nagasaki.

      At the same time, giants like Marie Curie inspired her to pursue science. Nuclear physics was particularly fascinating. “At some point during high school, I started wondering ‘what are radiations, what is radioactivity, what is light,’” she recalls. Reading Richard Feynman’s books and trying to understand quantum mechanics made her want to study physics in college.

      Pursuing research in the United States

      Wainwright pursued an undergraduate degree in engineering physics at Kyoto University. After two research internships in the United States, Wainwright was impressed by the dynamic and fast-paced research environment in the country.

      And compared to Japan, there were “more women in science and engineering,” Wainwright says. She enrolled at the University of California at Berkeley in 2005, where she completed her doctorate in nuclear engineering with minors in statistics and civil and environmental engineering.

      Before moving to MIT NSE in 2022, Wainwright was a staff scientist in the Earth and Environmental Area at Lawrence Berkeley National Laboratory (LBNL). She worked on a variety of topics, including radioactive contamination, climate science, CO2 sequestration, precision agriculture, and watershed science. Her time at LBNL helped Wainwright build a solid foundation about a variety of environmental sensors and monitoring and simulation methods across different earth science disciplines.   

      Empowering communities through monitoring

      One of the most compelling takeaways from Wainwright’s early research: People trust actual measurements and data as facts, even though they are skeptical about models and predictions. “I talked with many people living in Fukushima prefecture. Many of them have dosimeters and measure radiation levels on their own. They might not trust the government, but they trust their own data and are then convinced that it is safe to live there and to eat local food,” Wainwright says.

      She has been impressed that area citizens have gained significant knowledge about radiation and radioactivity through these efforts. “But they are often frustrated that people living far away, in cities like Tokyo, still avoid agricultural products from Fukushima,” Wainwright says.

      Wainwright thinks that data derived from environmental monitoring — through proper visualization and communication — can address misconceptions and fake news that often hurt people near contaminated sites.

      Wainwright is now interested in how these technologies — tested with real data at contaminated sites — can be proactively used for existing and future nuclear facilities “before contamination happens,” as she explored for Nuclear News. “I don’t think it is a good idea to simply dismiss someone’s concern as irrational. Showing credible data has been much more effective to provide assurance. Or a proper monitoring network would enable us to minimize contamination or support emergency responses when accidents happen,” she says.

      Educating communities and students

      Part of empowering communities involves improving their ability to process science-based information. “Potentially hazardous facilities always end up in rural regions; minorities’ concerns are often ignored. The problem is that these regions don’t produce so many scientists or policymakers; they don’t have a voice,” Wainwright says, “I am determined to dedicate my time to improve STEM education in rural regions and to increase the voice in these regions.”

      In a project funded by DOE, she collaborates with the team of researchers at the University of Alaska — the Alaska Center for Energy and Power and Teaching Through Technology program — aiming to improve STEM education for rural and indigenous communities. “Alaska is an important place for energy transition and environmental justice,” Wainwright says. Micro-nuclear reactors can potentially improve the life of rural communities who bear the brunt of the high cost of fuel and transportation. However, there is a distrust of nuclear technologies, stemming from past nuclear weapon testing. At the same time, Alaska has vast metal mining resources for renewable energy and batteries. And there are concerns about environmental contamination from mining and various sources. The teams’ vision is much broader, she points out. “The focus is on broader environmental monitoring technologies and relevant STEM education, addressing general water and air qualities,” Wainwright says.

      The issues also weave into the courses Wainwright teaches at MIT. “I think it is important for engineering students to be aware of environmental justice related to energy waste and mining as well as past contamination events and their recovery,” she says. “It is not OK just to send waste to, or develop mines in, rural regions, which could be a special place for some people. We need to make sure that these developments will not harm the environment and health of local communities.” Wainwright also hopes that this knowledge will ultimately encourage students to think creatively about engineering designs that minimize waste or recycle material.

      The last question of the final quiz of one of her recent courses was: Assume that you store high-level radioactive waste in your “backyard.” What technical strategies would make you and your family feel safe? “All students thought about this question seriously and many suggested excellent points, including those addressing environmental monitoring,” Wainwright says, “that made me hopeful about the future.” More

    • 150 Shares169 Views

      in Environment

      Detailed images from space offer clearer picture of drought effects on plants

      by

      “MIT is a place where dreams come true,” says César Terrer, an assistant professor in the Department of Civil and Environmental Engineering. Here at MIT, Terrer says he’s given the resources needed to explore ideas he finds most exciting, and at the top of his list is climate science. In particular, he is interested in plant-soil interactions, and how the two can mitigate impacts of climate change. In 2022, Terrer received seed grant funding from the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) to produce drought monitoring systems for farmers. The project is leveraging a new generation of remote sensing devices to provide high-resolution plant water stress at regional to global scales.

      Growing up in Granada, Spain, Terrer always had an aptitude and passion for science. He studied environmental science at the University of Murcia, where he interned in the Department of Ecology. Using computational analysis tools, he worked on modeling species distribution in response to human development. Early on in his undergraduate experience, Terrer says he regarded his professors as “superheroes” with a kind of scholarly prowess. He knew he wanted to follow in their footsteps by one day working as a faculty member in academia. Of course, there would be many steps along the way before achieving that dream. 

      Upon completing his undergraduate studies, Terrer set his sights on exciting and adventurous research roles. He thought perhaps he would conduct field work in the Amazon, engaging with native communities. But when the opportunity arose to work in Australia on a state-of-the-art climate change experiment that simulates future levels of carbon dioxide, he headed south to study how plants react to CO2 in a biome of native Australian eucalyptus trees. It was during this experience that Terrer started to take a keen interest in the carbon cycle and the capacity of ecosystems to buffer rising levels of CO2 caused by human activity.

      Around 2014, he began to delve deeper into the carbon cycle as he began his doctoral studies at Imperial College London. The primary question Terrer sought to answer during his PhD was “will plants be able to absorb predicted future levels of CO2 in the atmosphere?” To answer the question, Terrer became an early adopter of artificial intelligence, machine learning, and remote sensing to analyze data from real-life, global climate change experiments. His findings from these “ground truth” values and observations resulted in a paper in the journal Science. In it, he claimed that climate models most likely overestimated how much carbon plants will be able to absorb by the end of the century, by a factor of three. 

      After postdoctoral positions at Stanford University and the Universitat Autonoma de Barcelona, followed by a prestigious Lawrence Fellowship, Terrer says he had “too many ideas and not enough time to accomplish all those ideas.” He knew it was time to lead his own group. Not long after applying for faculty positions, he landed at MIT. 

      New ways to monitor drought

      Terrer is employing similar methods to those he used during his PhD to analyze data from all over the world for his J-WAFS project. He and postdoc Wenzhe Jiao collect data from remote sensing satellites and field experiments and use machine learning to come up with new ways to monitor drought. Terrer says Jiao is a “remote sensing wizard,” who fuses data from different satellite products to understand the water cycle. With Jiao’s hydrology expertise and Terrer’s knowledge of plants, soil, and the carbon cycle, the duo is a formidable team to tackle this project.

      According to the U.N. World Meteorological Organization, the number and duration of droughts has increased by 29 percent since 2000, as compared to the two previous decades. From the Horn of Africa to the Western United States, drought is devastating vegetation and severely stressing water supplies, compromising food production and spiking food insecurity. Drought monitoring can offer fundamental information on drought location, frequency, and severity, but assessing the impact of drought on vegetation is extremely challenging. This is because plants’ sensitivity to water deficits varies across species and ecosystems. 

      Terrer and Jiao are able to obtain a clearer picture of how drought is affecting plants by employing the latest generation of remote sensing observations, which offer images of the planet with incredible spatial and temporal resolution. Satellite products such as Sentinel, Landsat, and Planet can provide daily images from space with such high resolution that individual trees can be discerned. Along with the images and datasets from satellites, the team is using ground-based observations from meteorological data. They are also using the MIT SuperCloud at MIT Lincoln Laboratory to process and analyze all of the data sets. The J-WAFS project is among one of the first to leverage high-resolution data to quantitatively measure plant drought impacts in the United States with the hopes of expanding to a global assessment in the future.

      Assisting farmers and resource managers 

      Every week, the U.S. Drought Monitor provides a map of drought conditions in the United States. The map has zero resolution and is more of a drought recap or summary, unable to predict future drought scenarios. The lack of a comprehensive spatiotemporal evaluation of historic and future drought impacts on global vegetation productivity is detrimental to farmers both in the United States and worldwide.  

      Terrer and Jiao plan to generate metrics for plant water stress at an unprecedented resolution of 10-30 meters. This means that they will be able to provide drought monitoring maps at the scale of a typical U.S. farm, giving farmers more precise, useful data every one to two days. The team will use the information from the satellites to monitor plant growth and soil moisture, as well as the time lag of plant growth response to soil moisture. In this way, Terrer and Jiao say they will eventually be able to create a kind of “plant water stress forecast” that may be able to predict adverse impacts of drought four weeks in advance. “According to the current soil moisture and lagged response time, we hope to predict plant water stress in the future,” says Jiao. 

      The expected outcomes of this project will give farmers, land and water resource managers, and decision-makers more accurate data at the farm-specific level, allowing for better drought preparation, mitigation, and adaptation. “We expect to make our data open-access online, after we finish the project, so that farmers and other stakeholders can use the maps as tools,” says Jiao. 

      Terrer adds that the project “has the potential to help us better understand the future states of climate systems, and also identify the regional hot spots more likely to experience water crises at the national, state, local, and tribal government scales.” He also expects the project will enhance our understanding of global carbon-water-energy cycle responses to drought, with applications in determining climate change impacts on natural ecosystems as a whole. More

    • 75 Shares119 Views

      in Environment

      Engaging enterprises with the climate crisis

      by

      Almost every large corporation is committed to achieving net zero carbon emissions by 2050 but lacks a roadmap to get there, says John Sterman, professor of management at MIT’s Sloan School of Management, co-director of the MIT Sloan Sustainability Initiative, and leader of its Climate Pathways Project. Sterman and colleagues offer a suite of well-honed strategies to smooth this journey, including a free global climate policy simulator called En-ROADS deployed in workshops that have educated more than 230,000 people, including thousands of senior elected officials and leaders in business and civil society around the world. 

      Running on ordinary laptops, En-ROADS examines how we can reduce carbon emissions to keep global warming under 2 degrees Celsius, Sterman says. Users, expert or not, can easily explore how dozens of policies, such as pricing carbon and electrifying vehicles, can affect hundreds of factors such as temperature, energy prices, and sea level rise. 

      En-ROADs and related work on climate change are just one thread in Sterman’s decades of research to integrate environmental sustainability with business decisions. 

      “There’s a fundamental alignment between a healthy environment, a healthy society, and a healthy economy,” he says. “Destroy the environment and you destroy the economy and society. Likewise, hungry, ill-housed, insecure people, lacking decent jobs and equity in opportunity, will catch the last fish and cut the last tree, destroying the environment and society. Unfortunately, a lot of businesses still see the issue as a trade-off — if we focus on the environment, it will hurt our bottom line; if we improve working conditions, it will raise our labor costs. That turns out not to be true in many, many cases. But how can we help people understand that fundamental alignment? That’s where simulation models can play a big role.”

      Play video

      Learning with management flight simulators 

      “My original field is system dynamics, a method for understanding the complex systems in which we’re embedded—whether those are organizations, companies, markets, society as a whole, or the climate system” Sterman says. “You can build these wonderful, complex simulation models that offer important insights and insight into high-leverage policies so that organizations can make significant improvements.” 

      “But those models don’t do any good at all unless the folks in those organizations can learn for themselves about what those high-leverage opportunities are,” he emphasizes. “You can show people the best scientific evidence, the best data, and it’s not necessarily going to change their minds about what they ought to be doing. You’ve got to create a process that helps smart but busy people learn how they can improve their organizations.” 

      Sterman and his colleagues pioneered management flight simulators — which, like aircraft flight simulators, offer an environment in which you can make decisions, seeing what works and what doesn’t, at low cost with no risk. 

      “People learn best from experience and experiment,” he points out. “But in many of the most important settings that we face today, experience comes too late to be useful, and experiments are impossible. In such settings, simulation becomes the only way people can learn for themselves and gain the confidence to change their behavior in the real world.” 

      “You can’t learn to fly a new jetliner by watching someone else; to learn, one must be at the controls,” Sterman emphasizes. “People don’t change deeply embedded beliefs and behaviors just because somebody tells them that what they’re doing is harmful and there are better options. People have to learn for themselves.”

      Play video

      Learning the business of sustainability 

      His longstanding “laboratory for sustainable business” course lets MIT Sloan School students learn the state of the art in sustainability challenges — not just climate change but microplastics, water shortages, toxins in our food and air, and other crises. As part of the course, students work in teams with organizations on real sustainability challenges. “We’ve had a very wide range of companies and other organizations participate, and many of them come back year after year,” Sterman says. 

      MIT Sloan also offers executive education in sustainability, in both open enrollment and customized programs. “We’ve had all kinds of folks, from all over the world and every industry” he says. 

      In his opening class for executive MBAs, he polls attendees to ask if sustainability is a material issue for their companies, and how actively those companies are addressing that issue. Almost all of the attendees agree that sustainability is a key issue, but nearly all say their companies are not doing enough, with many saying they “comply with all applicable laws and regulations.” 

      “So there’s a huge disconnect,” Sterman points out. “How do you close that gap? How do you take action? How do you break the idea that if you take action to be more sustainable it will hurt your business, when in fact it’s almost always the other way around? And then how can you make the change happen, so that what you’re doing will get implemented and stick?” 

      Simulating policies for sustainability 

      Management flight simulators that offer active learning can provide crucial guidance. In the case of climate change, En-ROADs presents a straightforward interface that lets users adjust sliders to experiment with actions to try to bring down carbon emissions. “Should we have a price on carbon?” Sterman asks. “Should we promote renewables? Should we work on methane? Stop deforestation? You can try anything you want. You get immediate feedback on the likely consequences of your decisions. Often people are surprised as favorite policies — say, planting trees — have only minor impact on global warming. (In the case of trees, because it takes so long for the trees to grow).”

      One En-ROADS alumnus works for a pharmaceutical company that set a target of zero net emissions by mid-century. But, as often observed, measures proposed at the senior corporate level were often resisted by the operating units. The alumnus attacked the problem by bringing workshops with simulations and other sustainability tools to front-line employees in a manufacturing plant he knew well. He asked these employees how they thought they could reduce carbon emissions and what they needed to do so. 

      “It turns out that they had a long list of opportunities to reduce the emissions from this plant,” Sterman says. “But they didn’t have any support to get it done. He helped their ideas get that support, get the resources, come up with ways to monitor their progress, and ways to look for quick wins. It’s been highly successful.” 

      En-ROADS helps people understand that process improvement activity takes resources; you might need to take some equipment offline temporarily, for example, to upgrade or improve it. “There’s a little bit of a worse-before-better trade-off,” he says. “You need to be prepared. The active learning, the use of the simulators, helps people prepare for that journey and overcome the barriers that they will face.” 

      Interactive workshops with En-ROADS and other sustainability tools also brought change to another large corporation, HSBC Bank U.S.A. Like many other financial institutions, HSBC has committed to significantly cut its emissions, but many employees and executives didn’t understand why or what that would entail. For instance, would the bank give up potential business in carbon-intensive industries? 

      Brought to more than 1,000 employees, the En-ROADS workshops let employees surface concerns they might have about continuing to be successful while addressing climate concerns. “It turns out in many cases, there isn’t that much of a trade-off,” Sterman remarks. “Fossil energy projects, for example, are extremely risky. And there are opportunities to improve margins in other businesses where you can help cut their carbon footprint.” 

      The free version of En-ROADS generally satisfies the needs of most organizations, but Sterman and his partners also can augment the model or develop customized workshops to address specific concerns. 

      People who take the workshops emerge with a greater understanding of climate change and its effects, and a deeper knowledge of the high-leverage opportunities to cut emissions. “Even more importantly, they come out with a greater sense of urgency,” he says. “But they also come out with an understanding that it’s not too late. Time is short, but what we do can still make a difference.”  More

    • 88 Shares149 Views

      in Energy

      Working to make nuclear energy more competitive

      by

      Assil Halimi has loved science since he was a child, but it was a singular experience at a college internship that stoked his interest in nuclear engineering. As part of work on a conceptual design for an aircraft electric propulsion system, Halimi had to read a chart that compared the energy density of various fuel sources. He was floored to see that the value for uranium was orders of magnitude higher than the rest. “Just a fuel pellet the size of my fingertip can generate as much energy as a ton of coal or 150 gallons of oil,” Halimi points out.

      Having grown up in Algeria, in an economy dominated by oil and gas, Halimi was always aware of energy’s role in fueling growth. But here was a source that showed enormous potential. “The more I read about nuclear, the more I saw its direct relationship with climate change and how nuclear energy can potentially replace the carbonized economy,” Halimi says. “The problem we’re dealing with right now is that the source of energy is not clean. Nuclear [presented itself] as an answer, or at least as a promise that you can dig into,” he says. “I was also seeing the electrification of systems and the economy evolving.”

      A tectonic shift was brewing, and Halimi wanted in.

      Then an electrical engineering major at the Institut National des Sciences Appliquées de Lyon (INSA Lyon), Halimi added nuclear engineering as a second major. Today, the second-year doctoral student at MIT’s Department of Nuclear Science and Engineering (NSE) has expanded on his early curiosity in the field and researches methods of improving the design of small modular reactors. Under Professor Koroush Shirvan’s advisement, Halimi also studies high burnup fuel so we can extract more energy from the same amount of material.

      A foot in two worlds

      The son of a computer engineer father and a mother who works as a judge, Halimi was born in Algiers and grew up in Cherchell, a small town near the capital. His interest in science grew sharper in middle school; Halimi remembers being a member of the astronomy club. As a middle and high schooler, Halimi traveled to areas with low light pollution to observe the night skies.

      As a teenager, Halimi set his goals high, enrolling in high school in both Algeria and France. Taking classes in Arabic and French, he found a fair amount of overlap between the two curricula. The divergence in the nonscientific classes gave Halimi a better understanding of the cultural perspectives. After studying the French curriculum remotely, Halimi graduated with two diplomas. He remembers having to take two baccalaureate exams, which didn’t bother him much, but he did have to miss viewing parts of the 2014 World Cup soccer tournament.

      A multidisciplinary approach to engineering

      After high school, Halimi moved to France to study engineering at INSA Lyon. He elected for a major in electrical engineering and, ever the pragmatist, also signed up for a bachelor’s degree in math and economics. “You can build a lot of amazing things, but you have to take costs into account to make sure you’re proposing something feasible that can make it in the real world,” Halimi says, explaining his motivation to study economics.

      Wrapping up his bachelor’s in math and economics in two short years, Halimi decided to pursue a double curriculum in electrical and nuclear engineering during his final year of engineering studies. Since his school in Lyon did not offer the double curriculum, Halimi had to move to Paris to study at The French Alternative Energies and Atomic Energy Commission (CEA), part of the University of Paris-Saclay. The summer before he started, he traveled to Japan and toured the Fukushima nuclear power plant.

      Halimi first conducted research at MIT NSE as part of an internship in nuclear engineering when he was still a student in France. He remembers wanting to explore work on reactor design, when an advisor at CEA recommended interning with Shirvan.

      Pragmatism in nuclear energy adoption

      Halimi’s work at MIT NSE focuses on high burnup fuel assessment and small modular reactor (SMR) design.

      Existing nuclear plants have faced stiff competition during the last decade. Improving the fuel efficiency (high burnup) is a potential way of improving the economic competitiveness of the existing reactor fleet. One challenge is that materials degrade when you keep them longer in the reactor. Halimi evaluates fuel performance and safety features of more efficient fuel operation using advanced computer simulation tools. At the 2022 TopFuel Light Water Reactor Fuel Performance Conference, Halimi presented a paper describing strategies to achieve higher burnups. He is now working on journal paper about this work.

      Halimi’s research on SMR design is motivated by the industry’s move to smaller plants that take less time to construct. The challenge, he says, is that if you simply make the reactors smaller, you lose the advantages of economies of scale and might end up with a more expensive economic proposal. Halimi’s goal is to analyze how smaller reactors can compensate for economies of scale by improving their technical design. Other advantages stacked in favor of smaller reactors is that they can be constructed faster and in series.

      Halimi analyzes the fuel performance, core design, thermal hydraulics, and safety of these small reactors. “One efficient way that I particularly assess to improve their economics is high power density operation,” he says. In late 2021 Halimi published a paper on the relationship between cost and reactor power density in Nuclear Engineering and Design Journal. The research has been featured in other conference papers.

      When he’s not working, Halimi makes time to play soccer and hopes to get back into astronomy. “I sold all my gear when I moved from Europe so I need to buy new ones at some point,” he says.

      Halimi is convinced that nuclear power will be a serious contender in the energy landscape. “You have to propose something that will make everyone happy,” Halimi laughs when he describes work in nuclear science and engineering.

      The work ahead is daunting — “Nuclear power is safe, sustainable, and reliable; now we need to be on time and on budget [to achieve] climate goals” he says — but Halimi is ready. By addressing both the competitiveness of the existing reactors through high burnup fuels and designing the next generation of nuclear plants, he is adopting a dual-pronged approach to make nuclear energy an economical and viable alternative to carbon-based fuels. More