Climate change

Subterms

    More stories

    • 88 Shares99 Views

      in Energy

      Bringing sustainable and affordable electricity to all

      by

      When MIT electrical engineer Reja Amatya PhD ’12 arrived in Rwanda in 2015, she was whisked off to a village. She saw that diesel generators provided power to the local health center, bank, and shops, but like most of rural Rwanda, Karambi’s 200 homes did not have electricity. Amatya knew the hilly terrain would make it challenging to connect the village to high-voltage lines from the capital, Kigali, 50 kilometers away.

      While many consider electricity a basic human right, there are places where people have never flipped a light switch. Among the United Nations’ Sustainable Development Goals is global access to affordable, reliable, and sustainable energy by 2030. Recently, the U.N. reported that progress in global electrification had slowed due to the challenge of reaching those hardest to reach.

      Researchers from the MIT Energy Initiative (MITEI) and Comillas Pontifical University in Madrid created Waya Energy Inc., a Cambridge, Massachusetts-based startup commercializing MIT-developed planning and analysis software, to help governments determine the most cost-effective ways to provide electricity to all their citizens.

      The researchers’ 2015 trip to Rwanda marked the beginning of four years of phone calls, Zoom meetings, and international travel to help the east African country — still reeling from the 1994 genocide that killed more than a million people — develop a national electrification strategy and extend its power infrastructure.

      Amatya, Waya president and one of five Waya co-founders, knew that electrifying Karambi and the rest of the country would provide new opportunities for work, education, and connections — and the ability to charge cellphones, often an expensive and inconvenient undertaking.

      To date, Waya — with funding from the Asian Development Bank, the African Development Bank, the Inter-American Development Bank for Latin America, and the World Bank — has helped governments develop electrification plans in 22 countries on almost every continent, including in refugee camps in sub-Saharan Africa’s Sahel and Chad regions, where violence has led to 3 million internally displaced people.

      “With a modeling and visualization tool like ours, we are able to look at the entire spectrum of need and demand and say, ‘OK, what might be the most optimized solution?’” Amatya says.

      More than 15 graduate students and researchers from MIT and Comillas contributed to the development of Waya’s software under the supervision of Robert Stoner, the interim director at MITEI, and Ignacio Pérez-Arriaga, a visiting professor at the MIT Sloan School of Management from Comillas. Pérez-Arriaga looks at how changing electricity use patterns have forced utilities worldwide to rethink antiquated business models.

      The team’s Reference Electrification Model (REM) software pulls information from population density maps, satellite images, infrastructure data, and geospatial points of interest to determine where extending the grid will be most cost-effective and where other solutions would be more practical.

      “I always say we are agnostic to the technology,” Amatya says. “Traditionally, the only way to provide long-term reliable access was through the grid, but that’s changing. In many developing countries, there are many more challenges for utilities to provide reliable service.”

      Off-grid solutions

      Waya co-founder Stoner, who is also the founding director of the MIT Tata Center for Technology and Design, recognized early on that connecting homes to existing infrastructure was not always economically feasible. What’s more, billions of people with grid connections had unreliable access due to uneven regulation and challenging terrain.

      With Waya co-founders Andres Gonzalez-Garcia, a MITEI affiliate researcher, and Professor Fernando de Cuadra Garcia of Comillas, Pérez-Arriaga and Stoner led a team that developed a set of principles to guide universal regional electrification. Their approach — which they dubbed the Integrated Distribution Framework — incorporates elements of optimal planning as well as novel business models and regulation. Getting all three right is “necessary,” Stoner says, “if you want a viable long-term outcome.”

      Amatya says, “Initially, we designed REM to understand what the level of demand is in these countries with very rural and poor populations, and what the system should look like to serve it. We took a lot of that input into developing the model.” In 2019, Waya was created to commercialize the software and add consulting to the package of services the team provides.

      Now, in addition to advising governments and regulators on how to expand existing grids, Waya proposes options such as a mini-grid, powered by renewables like wind, hydropower, or solar, to serve single villages or large-scale mini-grid solutions for larger areas. In some cases, an even more localized, scalable solution is a mesh grid, which might consist of a single solar panel for a few houses that, over time, can be expanded and ultimately connected to the main grid.

      The REM software has been used to design off-grid systems for remote and mountainous regions in Uganda, Peru, Nigeria, Cambodia, Indonesia, India, and elsewhere. When Tata Power, India’s largest integrated power company, saw how well mini-grids would serve parts of east India, the company created a mini-grid division called Tata Renewables.

      Amatya notes that the REM software enables her to come up with an entire national electrification plan from her workspace in Cambridge. But site visits and on-the-ground partners are critical in helping the Waya team understand existing systems, engage with clients to assess demand, and identify stakeholders. In Haiti, an energy consultant reported that the existing grid had typically been operational only six out of every 24 hours. In Karambi, University of Rwanda students surveyed the village’s 200 families and helped lead a community-wide meeting.

      Waya connects with on-the-ground experts and agencies “who can engage directly with the government and other stakeholders, because many times those are the doors that we knock on,” Amatya says. “Local energy ministries, utilities, and regulators have to be open to regulatory change. They have to be open to working with financial institutions and new technology.”

      The goals of regulators, energy providers, funding agencies, and government officials must align in real time “to provide reliable access to energy for a billion people,” she says.

      Moving past challenges

      Growing up in Kathmandu, Amatya used to travel to remote villages with her father, an electrical engineer who designed cable systems for landlines for Nepal Telecom. She remembers being fascinated by the high-voltage lines crisscrossing Nepal on these trips. Now, she points out utility poles to her children and explains how the distribution lines carry power from local substations to customers.

      After majoring in engineering science and physics at Smith College, Amatya completed her PhD in electrical engineering at MIT in 2012. Within two years, she was traveling to off-grid communities in India as a research scientist exploring potential technologies for providing access. There were unexpected challenges: At the time, digitized geospatial data didn’t exist for many regions. In India in 2013, the team used phones to take pictures of paper maps spread out on tables. Team members now scour digital data available through Facebook, Google, Microsoft, and other sources for useful geographical information. 

      It’s one thing to create a plan, Amatya says, but how it gets utilized and implemented becomes a big question. With all the players involved — funding agencies, elected officials, utilities, private companies, and regulators within the countries themselves — it’s sometimes hard to know who’s responsible for next steps.

      “Besides providing technical expertise, our team engages with governments to, let’s say, develop a financial plan or an implementation plan,” she says. Ideally, Waya hopes to stay involved with each project long enough to ensure that its proposal becomes the national electrification strategy of the country. That’s no small feat, given the multiple players, the opaque nature of government, and the need to enact a regulatory framework where none may have existed.

      For Rwanda, Waya identified areas without service, estimated future demand, and proposed the most cost-effective ways to meet that demand with a mix of grid and off-grid solutions. Based on the electrification plan developed by the Waya team, officials have said they hope to have the entire country electrified by 2024.

      In 2017, by the time the team submitted its master plan, which included an off-grid solution for Karambi, Amatya was surprised to learn that electrification in the village had already occurred — an example, she says, of the challenging nature of local planning.

      Perhaps because of Waya’s focus and outreach efforts, Karambi had become a priority. However it happened, Amatya is happy that Karambi’s 200 families finally have access to electricity. More

    • 63 Shares189 Views

      in Energy

      Making aviation fuel from biomass

      by

      In 2021, nearly a quarter of the world’s carbon dioxide emissions came from the transportation sector, with aviation being a significant contributor. While the growing use of electric vehicles is helping to clean up ground transportation, today’s batteries can’t compete with fossil fuel-derived liquid hydrocarbons in terms of energy delivered per pound of weight — a major concern when it comes to flying. Meanwhile, based on projected growth in travel demand, consumption of jet fuel is projected to double between now and 2050 — the year by which the international aviation industry has pledged to be carbon neutral.

      Many groups have targeted a 100 percent sustainable hydrocarbon fuel for aircraft, but without much success. Part of the challenge is that aviation fuels are so tightly regulated. “This is a subclass of fuels that has very specific requirements in terms of the chemistry and the physical properties of the fuel, because you can’t risk something going wrong in an airplane engine,” says Yuriy Román-Leshkov, the Robert T. Haslam Professor of Chemical Engineering. “If you’re flying at 30,000 feet, it’s very cold outside, and you don’t want the fuel to thicken or freeze. That’s why the formulation is very specific.”

      Aviation fuel is a combination of two large classes of chemical compounds. Some 75 to 90 percent of it is made up of “aliphatic” molecules, which consist of long chains of carbon atoms linked together. “This is similar to what we would find in diesel fuels, so it’s a classic hydrocarbon that is out there,” explains Román-Leshkov. The remaining 10 to 25 percent consists of “aromatic” molecules, each of which includes at least one ring made up of six connected carbon atoms.

      In most transportation fuels, aromatic hydrocarbons are viewed as a source of pollution, so they’re removed as much as possible. However, in aviation fuels, some aromatic molecules must remain because they set the necessary physical and combustion properties of the overall mixture. They also perform one more critical task: They ensure that seals between various components in the aircraft’s fuel system are tight. “The aromatics get absorbed by the plastic seals and make them swell,” explains Román-Leshkov. “If for some reason the fuel changes, so can the seals, and that’s very dangerous.”

      As a result, aromatics are a necessary component — but they’re also a stumbling block in the move to create sustainable aviation fuels, or SAFs. Companies know how to make the aliphatic fraction from inedible parts of plants and other renewables, but they haven’t yet developed an approved method of generating the aromatic fraction from sustainable sources. As a result, there’s a “blending wall,” explains Román-Leshkov. “Since we need that aromatic content — regardless of its source — there will always be a limit on how much of the sustainable aliphatic hydrocarbons we can use without changing the properties of the mixture.” He notes a similar blending wall with gasoline. “We have a lot of ethanol, but we can’t add more than 10 percent without changing the properties of the gasoline. In fact, current engines can’t handle even 15 percent ethanol without modification.”

      No shortage of renewable source material — or attempts to convert it

      For the past five years, understanding and solving the SAF problem has been the goal of research by Román-Leshkov and his MIT team — Michael L. Stone PhD ’21, Matthew S. Webber, and others — as well as their collaborators at Washington State University, the National Renewable Energy Laboratory (NREL), and the Pacific Northwest National Laboratory. Their work has focused on lignin, a tough material that gives plants structural support and protection against microbes and fungi. About 30 percent of the carbon in biomass is in lignin, yet when ethanol is generated from biomass, the lignin is left behind as a waste product.

      Despite valiant efforts, no one has found an economically viable, scalable way to turn lignin into useful products, including the aromatic molecules needed to make jet fuel 100 percent sustainable. Why not? As Román-Leshkov says, “It’s because of its chemical recalcitrance.” It’s difficult to make it chemically react in useful ways. As a result, every year millions of tons of waste lignin are burned as a low-grade fuel, used as fertilizer, or simply thrown away.

      Understanding the problem requires understanding what’s happening at the atomic level. A single lignin molecule — the starting point of the challenge — is a big “macromolecule” made up of a network of many aromatic rings connected by oxygen and hydrogen atoms. Put simply, the key to converting lignin into the aromatic fraction of SAF is to break that macromolecule into smaller pieces while in the process getting rid of all of the oxygen atoms.

      In general, most industrial processes begin with a chemical reaction that prevents the subsequent upgrading of lignin: As the lignin is extracted from the biomass, the aromatic molecules in it react with one another, linking together to form strong networks that won’t react further. As a result, the lignin is no longer useful for making aviation fuels.

      To avoid that outcome, Román-Leshkov and his team utilize another approach: They use a catalyst to induce a chemical reaction that wouldn’t normally occur during extraction. By reacting the biomass in the presence of a ruthenium-based catalyst, they are able to remove the lignin from the biomass and produce a black liquid called lignin oil. That product is chemically stable, meaning that the aromatic molecules in it will no longer react with one another.

      So the researchers have now successfully broken the original lignin macromolecule into fragments that contain just one or two aromatic rings each. However, while the isolated fragments don’t chemically react, they still contain oxygen atoms. Therefore, one task remains: finding a way to remove the oxygen atoms.

      In fact, says Román-Leshkov, getting from the molecules in the lignin oil to the targeted aromatic molecules required them to accomplish three things in a single step: They needed to selectively break the carbon-oxygen bonds to free the oxygen atoms; they needed to avoid incorporating noncarbon atoms into the aromatic rings (for example, atoms from the hydrogen gas that must be present for all of the chemical transformations to occur); and they needed to preserve the carbon backbone of the molecule — that is, the series of linked carbon atoms that connect the aromatic rings that remain.

      Ultimately, Román-Leshkov and his team found a special ingredient that would do the trick: a molybdenum carbide catalyst. “It’s actually a really amazing catalyst because it can perform those three actions very well,” says Román-Leshkov. “In addition to that, it’s extremely resistant to poisons. Plants can contain a lot of components like proteins, salts, and sulfur, which often poison catalysts so they don’t work anymore. But molybdenum carbide is very robust and isn’t strongly influenced by such impurities.”

      Trying it out on lignin from poplar trees

      To test their approach in the lab, the researchers first designed and built a specialized “trickle-bed” reactor, a type of chemical reactor in which both liquids and gases flow downward through a packed bed of catalyst particles. They then obtained biomass from a poplar, a type of tree known as an “energy crop” because it grows quickly and doesn’t require a lot of fertilizer.

      To begin, they reacted the poplar biomass in the presence of their ruthenium-based catalyst to extract the lignin and produce the lignin oil. They then flowed the oil through their trickle-bed reactor containing the molybdenum carbide catalyst. The mixture that formed contained some of the targeted product but also a lot of others that still contained oxygen atoms.

      Román-Leshkov notes that in a trickle-bed reactor, the time during which the lignin oil is exposed to the catalyst depends entirely on how quickly it drips down through the packed bed. To increase the exposure time, they tried passing the oil through the same catalyst twice. However, the distribution of products that formed in the second pass wasn’t as they had predicted based on the outcome of the first pass.

      With further investigation, they figured out why. The first time the lignin oil drips through the reactor, it deposits oxygen onto the catalyst. The deposition of the oxygen changes the behavior of the catalyst such that certain products appear or disappear — with the temperature being critical. “The temperature and oxygen content set the condition of the catalyst in the first pass,” says Román-Leshkov. “Then, on the second pass, the oxygen content in the flow is lower, and the catalyst can fully break the remaining carbon-oxygen bonds.” The process can thus operate continuously: Two separate reactors containing independent catalyst beds would be connected in series, with the first pretreating the lignin oil and the second removing any oxygen that remains.

      Based on a series of experiments involving lignin oil from poplar biomass, the researchers determined the operating conditions yielding the best outcome: 350 degrees Celsius in the first step and 375 C in the second step. Under those optimized conditions, the mixture that forms is dominated by the targeted aromatic products, with the remainder consisting of small amounts of other jet-fuel aliphatic molecules and some remaining oxygen-containing molecules. The catalyst remains stable while generating more than 87 percent (by weight) of aromatic molecules.

      “When we do our chemistry with the molybdenum carbide catalyst, our total carbon yields are nearly 85 percent of the theoretical carbon yield,” says Román-Leshkov. “In most lignin-conversion processes, the carbon yields are very low, on the order of 10 percent. That’s why the catalysis community got very excited about our results — because people had not seen carbon yields as high as the ones we generated with this catalyst.”

      There remains one key question: Does the mixture of components that forms have the properties required for aviation fuel? “When we work with these new substrates to make new fuels, the blend that we create is different from standard jet fuel,” says Román-Leshkov. “Unless it has the exact properties required, it will not qualify for certification as jet fuel.”

      To check their products, Román-Leshkov and his team send samples to Washington State University, where a team operates a combustion lab devoted to testing fuels. Results from initial testing of the composition and properties of the samples have been encouraging. Based on the composition and published prescreening tools and procedures, the researchers have made initial property predictions for their samples, and they looked good. For example, the freezing point, viscosity, and threshold sooting index are predicted to be lower than the values for conventional aviation aromatics. (In other words, their material should flow more easily and be less likely to freeze than conventional aromatics while also generating less soot in the atmosphere when they burn.) Overall, the predicted properties are near to or more favorable than those of conventional fuel aromatics.

      Next steps

      The researchers are continuing to study how their sample blends behave at different temperatures and, in particular, how well they perform that key task: soaking into and swelling the seals inside jet engines. “These molecules are not the typical aromatic molecules that you use in jet fuel,” says Román-Leshkov. “Preliminary tests with sample seals show that there’s no difference in how our lignin-derived aromatics swell the seals, but we need to confirm that. There’s no room for error.”

      In addition, he and his team are working with their NREL collaborators to scale up their methods. NREL has much larger reactors and other infrastructure needed to produce large quantities of the new sustainable blend. Based on the promising results thus far, the team wants to be prepared for the further testing required for the certification of jet fuels. In addition to testing samples of the fuel, the full certification procedure calls for demonstrating its behavior in an operating engine — “not while flying, but in a lab,” clarifies Román-Leshkov. In addition to requiring large samples, that demonstration is both time-consuming and expensive — which is why it’s the very last step in the strict testing required for a new sustainable aviation fuel to be approved.

      Román-Leshkov and his colleagues are now exploring the use of their approach with other types of biomass, including pine, switchgrass, and corn stover (the leaves, stalks, and cobs left after corn is harvested). But their results with poplar biomass are promising. If further testing confirms that their aromatic products can replace the aromatics now in jet fuel, “the blending wall could disappear,” says Román-Leshkov. “We’ll have a means of producing all the components in aviation fuel from renewable material, potentially leading to aircraft fuel that’s 100 percent sustainable.”

      This research was initially funded by the Center for Bioenergy Innovation, a U.S. Department of Energy (DOE) Research Center supported by the Office of Biological and Environmental Research in the DOE Office of Science. More recent funding came from the DOE Bioenergy Technologies Office and from Eni S.p.A. through the MIT Energy Initiative. Michael L. Stone PhD ’21 is now a postdoc in chemical engineering at Stanford University. Matthew S. Webber is a graduate student in the Román-Leshkov group, now on leave for an internship at the National Renewable Energy Laboratory.

      This article appears in the Spring 2023 issue of Energy Futures, the magazine of the MIT Energy Initiative. More

    • 100 Shares199 Views

      in Environment

      Q&A: Steven Gonzalez on Indigenous futurist science fiction

      by

      Steven Gonzalez is a PhD candidate in the MIT Doctoral Program in History, Anthropology, Science, Technology, and Society (HASTS), where he researches the environmental impacts of cloud computing and data centers in the United States, Iceland, and Puerto Rico. He is also an author. Writing under the name E.G. Condé, he recently published his first book, “Sordidez.” It’s described as an “Indigenous futurist science fiction novella set in Puerto Rico and the Yucatán.” Set in the near future, it follows the survivors of civil war and climate disaster led by protagonist Vero Diaz, as they reclaim their Indigenous heritage and heal their lands.

      In this Q&A, Gonzalez describes the book’s themes, its inspirations, and its connection to research, people, and classes at MIT.

      Q: Where did the inspiration for this story come from?

      A: I actually began my time at MIT in September of 2017 when Hurricane María struck. It was a really difficult time for me at the Institute, starting a PhD program. And it’s MIT, so there’s a lot of pressure. I was still kind of navigating the new institutional space and trying to understand my place in it. But I had a lot of people at the Institute who were extremely supportive during that time. I had family members in Puerto Rico who were stranded as a result of the hurricane, who I didn’t hear from for a very long time — who I feared dead. It was a very, very chaotic, confusing, and emotionally turbulent time for me, and also incredibly difficult to be trying to be present in a PhD program for the first semester. Karen Gardner, our administrator, was really incredibly supportive in that. Also the folks at the MIT Association of Puerto Ricans, who hosted fundraisers and linked students with counseling resources. But that trauma of the hurricane and the images that I saw of the aftermath of the hurricane, specifically in the town where my grandmother’s house was where I spent time living as a child during the summers, and to me, it was the greenest place that I have ever known. It looked like somebody had torched the entire landscape. It was traumatizing to see that image. But that kind of seeded the idea of, is there a way to burn without fire? There’s climate change, but there’s also climate terror. And so that was sort of one of the premises of the book explores, geoengineering, but also the flip side of geoengineering and terraforming is, of course, climate terror. And in a way, we could frame what’s been happening with the fossil fuel industry as a form of climate terror, as well. So for me, this all began right when I started at MIT, these dual tracks of thought.

      Q: What do you see as the core themes of your novella?

      A: One major theme is rebuilding. As I said, this story was very influenced by the trauma of Hurricane María and the incredibly inspiring accounts from family members, from people in Puerto Rico that I know, of regular people stepping up when the government — both federal and local — essentially abandoned them. There were so many failures of governance. But people stepped up and did what they could to help each other, to help neighbors. Neighbors cleared trees from roads. They banded together to do this. They pooled resources, to run generators so that everyone in the same street could have food that day. They would share medical supplies like insulin and things that were scarce. This was incredibly inspiring for me. And a huge theme of the book is rebuilding in the aftermath of a fictive hurricane, which I call Teddy, named after President Theodore Roosevelt, where Puerto Rico’s journey began as a U.S. commonwealth or a colony.

      Healing is also a huge theme. Healing in the sense of this story was also somewhat critical of Puerto Rican culture. And it’s refracted through my own experience as a queer person navigating the space of Puerto Rico as a very kind of religious and traditional place and a very complex place at that. The main character, Vero, is a trans man. This is a person who’s transitioned and has felt a lot of alienation and as a result of his gender transition, a lot of people don’t accept him and don’t accept his identity or who he is even though he’s incredibly helpful in this rebuilding effort to the point where he’s, in some ways, a leader, if not the leader. And it becomes, in a way, about healing from the trauma of rejection too. And of course, Vero, but other characters who have gone through various traumas that I think are very much shared across Latin America, the Latin American experiences of assimilation, for instance. Latin America is a very complex place. We have Spanish as our language, that is our kind of lingua franca. But there are many Indigenous languages that people speak that have been not valued or people who speak them or use them are actively punished. And there’s this deep trauma of losing language. And in the case of Puerto Rico, the Indigenous language of the Taínos has been destroyed by colonialism. The story is about rebuilding that language and healing and “becoming.” In some ways, it’s about re-indigenization. And then the last part, as I said, healing, reconstruction, but also transformation and metamorphosis. And becoming Taíno. Again, what does that mean? What does it mean to be an Indigenous Caribbean in the future? And so that’s one of the central themes of the story.

      Q: How does the novella intersect with the work you’re doing as a PhD candidate in HASTS?

      A: My research on cloud computing is very much about climate change. It’s pitched within the context of climate change and understanding how our digital ecosystem contributes to not only global warming, but things like desertification. As a social scientist, that’s what I study. My studies of infrastructure are also directly referenced in the book in a lot of ways. For instance, the now collapsed Arecibo Ionosphere Observatory, where some of my pandemic fieldwork occurred, is a setting in the book. And also, I am an anthropologist. I am Puerto Rican. I draw both from my personal experience and my anthropological lens to make a story that I think is very multicultural and multilingual. It’s set in Puerto Rico, but the other half is set in the Yucatán Peninsula in what we’ll call the former Maya world. And there’s a lot of intersections between the two settings. And that goes back to the deeper Indigenous history. Some people are calling this Indigenous futurism because it references the Taínos, who are the Indigenous people of Puerto Rico, but also the Mayas, and many different Maya groups that are throughout the Yucatán Peninsula, but also present-day Guatemala and Honduras. And the story is about exchange between these two worlds. As someone trained as an anthropologist, it’s a really difficult task to kind of pull that off. And I think that my training has really, really helped me achieve that.

      Q: Are there any examples of ways being among the MIT community while writing this book influenced and, in some ways, made this project possible?

      A: I relied on many of my colleagues for support. There’s some sign language in the book. In Puerto Rico, there’s a big tradition of sign language. There’s a version of American sign language called LSPR that’s only found in Puerto Rico. And that’s something I’ve been aware of ever since I was a kid. But I’m not fluent in sign language or deaf communities and their culture. I got a lot of help from Timothy Loh, who’s in the HASTS program, who was extremely helpful to steer me towards sensitivity readers in the deaf community in his networks. My advisor, Stefan Helmreich, is very much a science fiction person in a lot of ways. His research is on the ocean waves, the history and anthropology of biology. He’s done ethnography in deep-sea submersibles. He’s always kind of thinking in a science fictional lens. And he allowed me, for one of my qualifying exam lists, to mesh science fiction with social theory. And that was also a way that I felt very supported by the Institute. In my coursework, I also took a few science fiction courses in other departments. I worked with Shariann Lewitt, who actually read the first version of the story. I workshopped it in her 21W.759 (Writing Science Fiction) class, and got some really amazing feedback that led to what is now a publication and a dream fulfilled in so many ways. She took me under her wing and really believed in this book. More

    • 75 Shares99 Views

      in Environment

      MIT at the 2023 Venice Biennale

      by

      The Venice Architecture Biennale, the world’s largest and most visited exhibition focusing on architecture, is once again featuring work by many MIT faculty, students, and alumni. On view through Nov. 26, the 2023 biennale, curated by Ghanaian-Scottish architect, academic, and novelist Lesley Lokko, is showcasing projects responding to the theme of “The Laboratory of Change.”

      Architecture and Planning and curator of the previous Venice Biennale. “Our students, faculty, and alumni have responded to the speculative theme with innovative projects at a range of scales and in varied media.”

      Below are descriptions of MIT-related projects and activities.

      MIT faculty participants

      Xavi Laida Aguirre, assistant professor of architecture

      Project: Everlasting Plastics

      Project description: SPACES, a nonprofit alternative art organization based in Cleveland, Ohio, and the U.S. Department of State’s Bureau of Educational and Cultural Affairs are behind the U.S. Pavilion’s exhibition at this year’s biennale. The theme, Everlasting Plastics, provides a platform for artists and designers to engage audiences in reframing the overabundance of plastic detritus in our waterways, landfills, and streets as a rich resource. Aguirre’s installation covers two rooms and holds a series of partial scenographies examining indoor proofing materials such as coatings, rubbers, gaskets, bent aluminum, silicone, foam, cement board, and beveled edges.

      Yolande Daniels, associate professor of architecture

      Project: The BLACK City Astrolabe: A Constellation of African Diasporic Women

      Project description: From the multiple displacements of race and gender, enter “The BLACK City Astrolabe,” a space-time field comprised of a 3D map and a 24-hour cycle of narratives that reorder the forces of subjugation, devaluation, and displacement through the spaces and events of African diasporic women. The diaspora map traces the flows of descendants of Africa (whether voluntary or forced) atop the visible tension between the mathematical regularity of meridians of longitude and the biases of international date lines.

      In this moment we are running out of time. The meridians and timeline decades are indexed to an infinite conical projection metered in decades. It structures both the diaspora map and timeline and serves as a threshold to project future structures and events. “The BLACK City Astrolabe” is a vehicle to proactively contemplate things that have happened, that are happening, and that will happen. Yesterday, a “Black” woman went to the future, and here she is.

      Mark Jarzombek, professor of architecture

      Project: Kishkindha NY

      Project description: “Kishkindha NY (Office of (Un)Certainty Research: Mark Jarzombek and Vikramaditya Parakash)” is inspired by an imagined forest-city as described in the ancient Indian text the Ramayana. It comes into being not through the limitations of human agency, but through a multi-species creature that destroys and rebuilds. It is exhibited as a video (Space, Time, Existence) and as a special dance performance.

      Ana Miljački, professor of architecture

      Team: Ana Miljački, professor of architecture and director of Critical Broadcasting Lab, MIT; Ous Abou Ras, MArch candidate; Julian Geltman, MArch; Recording and Design, faculty of Dramatic Arts, Belgrade; Calvin Zhong, MArch candidate. Sound design and production: Pavle Dinulović, assistant professor, Department of Sound Recording and Design, University of Arts in Belgrade.

      Collaborators: Melika Konjičanin, researcher, faculty of architecture, Sarajevo; Ana Martina Bakić, assistant professor, head of department of drawing and visual design, faculty of architecture, Zagreb; Jelica Jovanović, Grupa Arhitekata, Belgrade; Andrew Lawler, Belgrade; Sandro Đukić, CCN Images, Zagreb; Other Tomorrows, Boston.

      Project: The Pilgrimage/Pionirsko hodočašće

      Project description:  The artifacts that constitute Yugoslavia’s socialist architectural heritage, and especially those instrumental in the ideological wiring of several postwar generations for anti-fascism and inclusive living, have been subject to many forms of local and global political investment in forgetting their meaning, as well as to vandalism. The “Pilgrimage” synthesizes “memories” from Yugoslavian childhood visits to myriad postwar anti-fascist memorial monuments and offers them in a shifting and spatial multi-channel video presentation accompanied by a nonlinear documentary soundscape, presenting thus anti-fascism and unity as political and activist positions available (and necessary) today, for the sake of the future. Supported by: MIT Center for Art, Science, and Technology (CAST) Mellon Faculty Grant.

      Adèle Naudé Santos, professor of architecture, planning, and urban design; and Mohamad Nahleh, lecturer in architecture and urbanism; in collaboration with the Beirut Urban Lab at the American University of Beirut

      MIT research team: Ghida El Bsat, Joude Mabsout, Sarin Gacia Vosgerichian, Lasse Rau

      Project: Housing as Infrastructure

      Project description: On Aug. 4, 2020, an estimated 2,750 tons of ammonium nitrate stored at the Port of Beirut exploded, resulting in the deaths of more than 200 people and the devastation of port-adjacent neighborhoods. With over 200,000 housing units in disrepair, exploitative real estate ventures, and the lack of equitable housing policies, we viewed the port blast as a potential escalation of the mechanisms that have produced the ongoing affordable housing crisis across the city. 

      The Dar Group requested proposals to rethink the affected part of the city, through MIT’s Norman B. Leventhal Center for Advanced Urbanism. To best ground our design proposal, we invited the Beirut Urban Lab at the American University of Beirut to join us. We chose to work on the heavily impacted low-rise and high-density neighborhood of Mar Mikhael. Our resultant urban strategy anchors housing within a corridor of shared open spaces. Housing is inscribed within this network and sustained through an adaptive system defined by energy-efficiency and climate responsiveness. Cross-ventilation sweeps through the project on all sides, with solar panel lined roofs integrated to always provide adequate levels of electricity for habitation. These strategies are coupled with an array of modular units designed to echo the neighborhood’s intimate quality — all accessible through shared ramps and staircases. Within this context, housing itself becomes the infrastructure, guiding circulation, managing slopes, integrating green spaces, and providing solar energy across the community. 

      Rafi Segal, associate professor of architecture and urbanism, director of the Future Urban Collectives Lab, director of the SMArchS program; and Susannah Drake.

      Contributors: Olivia Serra, William Minghao Du

      Project:  From Redlining to Blue Zoning: Equity and Environmental Risk, Miami 2100 (2021)

      Project description: As part of Susannah Drake and Rafi Segal’s ongoing work on “Coastal Urbanism,” this project examines the legacy of racial segregation in South Florida and the existential threat that climate change poses to communities in Miami. Through models of coops and community-owned urban blocks, this project seeks to empower formerly disenfranchised communities with new methods of equity capture, allowing residents whose parents and grandparents suffered from racial discrimination to build wealth and benefit from increased real estate value and development.

      Nomeda Urbonas, Art, Culture, and Technology research affiliate; and Gediminas Urbonas, ACT associate professor

      Project: The Swamp Observatory

      Project description: “The Swamp Observatory” augmented reality app is a result of two-year collaboration with a school in Gotland Island in the Baltic Sea, arguably the most polluted sea in the world. Developed as a conceptual playground and a digital tool to augment reality with imaginaries for new climate commons, the app offers new perspective to the planning process, suggesting eco-monsters as emergent ecology for the planned stormwater ponds in the new sustainable city. 

      Sarah Williams, associate professor, technology and urban planning

      Team members: listed here.

      Project: DISTANCE UNKNOWN: RISKS AND OPPORTUNITIES OF MIGRATION IN THE AMERICAS 

      Project description: On view are visualizations made by the MIT Civic Data Design Lab and the United Nations World Food Program that helped to shape U.S. migration policy. The exhibition is built from a unique dataset collected from 4,998 households surveyed in El Salvador, Guatemala, and Honduras. A tapestry woven out of money and constructed by the hands of Central America migrants illustrates that migrants spent $2.2 billion to migrate from Central America in 2021.

      MIT student curators

      Carmelo Ignaccolo, PhD candidate, Department of Urban Studies and Planning (DUSP)

      Curator: Carmelo Ignaccolo; advisor: Sarah Williams; researchers: Emily Levenson (DUSP), Melody Phu (MIT), Leo Saenger (Harvard University), Yuke Zheng (Harvard); digital animation designer: Ting Zhang

      Exhibition Design Assistant: Dila Ozberkman (architecture and DUSP)

      Project: The Consumed City 

      Project description: “The Consumed City” narrates a spatial investigation of “overtourism” in the historic city of Venice by harnessing granular data on lodging, dining, and shopping. The exhibition presents two large maps and digital animations to showcase the complexity of urban tourism and to reveal the spatial interplay between urban tourism and urban features, such as landmarks, bridges, and street patterns. By leveraging by-product geospatial datasets and advancing visualization techniques, “The Consumed City” acts as a prototype to call for novel policymaking tools in cities “consumed” by “overtourism.”

      MIT-affiliated auxiliary events

      Rania Ghosn, associate professor of architecture and urbanism, El Hadi Jazairy, Anhong Li, and Emma Jurczynski, with initial contributions from Marco Nieto and Zhifei Xu. Graphic design: Office of Luke Bulman.

      Project: Climate Inheritance

      Project description: “Climate Inheritance” is a speculative design research publication that reckons with the complexity of “heritage” and “world” in the Anthropocene Epoch. The impacts of climate change on heritage sites — from Venice flooding to extinction in the Galapagos Islands — have garnered empathetic attention in a media landscape that has otherwise mostly failed to communicate the urgency of the climate crisis. In a strategic subversion of the media aura of heritage, the project casts World Heritage sites as narrative figures to visualize pervasive climate risks all while situating the present emergency within the wreckage of other ends of worlds, replete with the salvages of extractivism, racism, and settler colonialism.   

      Rebuilding Beirut: Using Data to Co-Design a New Future

      SA+P faculty, researchers, and students are participating in the sixth biennial architecture exhibition “Time Space Existence,” presented by the European Cultural Center. The exhibit showcases three collaborative research and design proposals that support the rebuilding efforts in Beirut following the catastrophic explosion at the Port of Beirut in August 2020.

      “Living Heritage Atlas” captures the significance and vulnerability of Beirut’s cultural heritage. 

      “City Scanner” tracks the environmental impacts of the explosion and the subsequent rebuilding efforts. “Community Streets” supports the redesign of streets and public space. 

      The work is supported by the Dar Group Urban Seed Grant Fund at MIT’s Norman B. Leventhal Center for Advanced Urbanism.

      Team members:Living Heritage AtlasCivic Data Design Lab and Future Heritage Lab at MITAssociate Professor Sarah Williams, co-principal investigator (PI)Associate Professor Azra Aksamija, co-PICity Scanner Senseable City Lab at MIT with the American University of Beirut and FAE Technology Professor Carlo Ratti, co-PIFábio Duarte, co-PISimone Mora, research and project leadCommunity Streets City Form Lab at MIT with the American University of BeirutAssociate Professor Andres Sevtsuk, co-PIProfessor Maya Abou-Zeid, co-PISchool of Architecture and Planning alumni participants   Rodrigo Escandón Cesarman SMArchS Design ’20 (co-curator, Mexican Pavilion)Felecia Davis PhD ’17 Design and Computation, SOFTLAB@PSU (Penn State University)Jaekyung Jung SM ’10, (with the team for the Korean pavilion)Vijay Rajkumar MArch ’22 (with the team for the Bahrain Pavilion)

      Other MIT alumni participants

      Basis with GKZ

      Team: Emily Mackevicius PhD ’18, brain and cognitive sciences, with Zenna Tavares, Kibwe Tavares, Gaika Tavares, and Eli Bingham

      Project description: The nonprofit research group works on rethinking AI as a “reasoning machine.” Their two goals are to develop advanced technological models and to make society able to tackle “intractable problems.” Their approach to technology is founded less on pattern elaboration than on the Bayes’ hypothesis, the ability of machines to work on abductive reasoning, which is the same used by the human mind. Two city-making projects model cities after interaction between experts and stakeholders, and representation is at the heart of the dialogue. More

    • 138 Shares179 Views

      in Energy

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

      by

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

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

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

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

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

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

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

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

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

      The hard truth about soft costs

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

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

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

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

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

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

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

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

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

      Static soft technology

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

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

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

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

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

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

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

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

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

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

    • 125 Shares179 Views

      in Energy

      A welcome new pipeline for students invested in clean energy

      by

      Akarsh Aurora aspired “to be around people who are actually making the global energy transition happen,” he says. Sam Packman sought to “align his theoretical and computational interests to a clean energy project” with tangible impacts. Lauryn Kortman says she “really liked the idea of an in-depth research experience focused on an amazing energy source.”

      These three MIT students found what they wanted in the Fusion Undergraduate Scholars (FUSars) program launched by the MIT Plasma Science and Fusion Center (PSFC) to make meaningful fusion energy research accessible to undergraduates. Aurora, Kortman, and Packman are members of a cohort of 10 for the program’s inaugural run, which began spring semester 2023.

      FUSars operates like a high-wattage UROP (MIT’s Undergraduate Research Opportunities Program). The program requires a student commitment of 10 to 12 hours weekly on a research project during the course of an academic year, as well as participation in a for-credit seminar providing professional development, communication, and wellness support. Through this class and with the mentorship of graduate students, postdocs, and research scientist advisors, students craft a publication-ready journal submission summarizing their research. Scholars who complete the entire year and submit a manuscript for review will receive double the ordinary UROP stipend — a payment that can reach $9,000.

      “The opportunity just jumped out at me,” says Packman. “It was an offer I couldn’t refuse,” adds Aurora.

      Building a workforce

      “I kept hearing from students wanting to get into fusion, but they were very frustrated because there just wasn’t a pipeline for them to work at the PSFC,” says Michael Short, Class of ’42 Associate Professor of Nuclear Science and Engineering and associate director of the PSFC. The PSFC bustles with research projects run by scientists and postdocs. But since the PSFC isn’t a university department with educational obligations, it does not have the regular machinery in place to integrate undergraduate researchers.

      This poses a problem not just for students but for the field of fusion energy, which holds the prospect of unlimited, carbon-free electricity. There are promising advances afoot: MIT and one of its partners, Commonwealth Fusion Systems, are developing a prototype for a compact commercial fusion energy reactor. The start of a fusion energy industry will require a steady infusion of skilled talent.

      “We have to think about the workforce needs of fusion in the future and how to train that workforce,” says Rachel Shulman, who runs the FUSars program and co-instructs the FUSars class with Short. “Energy education needs to be thinking right now about what’s coming after solar, and that’s fusion.”

      Short, who earned his bachelor’s, master’s, and doctoral degrees at MIT, was himself the beneficiary of the Undergraduate Research Opportunity Program (UROP) at the PSFC. As a faculty member, he has become deeply engaged in building transformative research experiences for undergraduates. With FUSars, he hopes to give students a springboard into the field — with an eye to developing a diverse, highly trained, and zealous employee pool for a future fusion industry.

      Taking a deep dive

      Although these are early days for this initial group of FUSars, there is already a shared sense of purpose and enthusiasm. Chosen from 32 applicants in a whirlwind selection process — the program first convened in early February after crafting the experience over Independent Activities Period — the students arrived with detailed research proposals and personal goals.

      Aurora, a first-year majoring in mechanical engineering and artificial intelligence, became fixed on fusion while still in high school. Today he is investigating methods for increasing the availability, known as capacity factor, of fusion reactors. “This is key to the commercialization of fusion energy,” he says.

      Packman, a first-year planning on a math and physics double major, is developing approaches to help simplify the computations involved in designing the complex geometries of solenoid induction heaters in fusion reactors. “This project is more immersive than my last UROP, and requires more time, but I know what I’m doing here and how this fits into the broader goals of fusion science,” he says. “It’s cool that our project is going to lead to a tool that will actually be used.”

      To accommodate the demands of their research projects, Shulman and Short discouraged students from taking on large academic loads.

      Kortman, a junior majoring in materials science and engineering with a concentration in mechanical engineering, was eager to make room in her schedule for her project, which concerns the effects of radiation damage on superconducting magnets. A shorter research experience with the PSFC during the pandemic fired her determination to delve deeper and invest more time in fusion.

      “It is very appealing and motivating to join people who have been working on this problem for decades, just as breakthroughs are coming through,” she says. “What I’m doing feels like it might be directly applicable to the development of an actual fusion reactor.”

      Camaraderie and support

      In the FUSar program, students aim to seize a sizeable stake in a multipronged research enterprise. “Here, if you have any hypotheses, you really get to pursue those because at the end of the day, the paper you write is yours,” says Aurora. “You can take ownership of what sort of discovery you’re making.”

      Enabling students to make the most of their research experiences requires abundant support — and not just for the students. “We have a whole separate set of programming on mentoring the mentors, where we go over topics with postdocs like how to teach someone to write a research paper, rather than write it for them, and how to help a student through difficulties,” Shulman says.

      The weekly student seminar, taught primarily by Short and Shulman, covers pragmatic matters essential to becoming a successful researcher — topics not always addressed directly or in the kind of detail that makes a difference. Topics include how to collaborate with lab mates, deal with a supervisor, find material in the MIT libraries, produce effective and persuasive research abstracts, and take time for self-care.

      Kortman believes camaraderie will help the cohort through an intense year. “This is a tight-knit community that will be great for keeping us all motivated when we run into research issues,” she says. “Meeting weekly to see what other students are able to accomplish will encourage me in my own project.”

      The seminar offerings have already attracted five additional participants outside the FUSars cohort. Adria Peterkin, a second-year graduate student in nuclear science and engineering, is sitting in to solidify her skills in scientific writing.

      “I wanted a structured class to help me get good at abstracts and communicating with different audiences,” says Peterkin, who is investigating radiation’s impact on the molten salt used in fusion and advanced nuclear reactors. “There’s a lot of assumed knowledge coming in as a PhD student, and a program like FUSars is really useful to help level out that playing field, regardless of your background.”

      Fusion research for all

      Short would like FUSars to cast a wide net, capturing the interest of MIT undergraduates no matter their backgrounds or financial means. One way he hopes to achieve this end is with the support of private donors, who make possible premium stipends for fusion scholars.

      “Many of our students are economically disadvantaged, on financial aid or supporting family back home, and need work that pays more than $15 an hour,” he says. This generous stipend may be critical, he says, to “flipping students from something else to fusion.”

      Although this first FUSars class is composed of science and engineering students, Short envisions a cohort eventually drawn from the broad spectrum of MIT disciplines. “Fusion is not a nuclear-focused discipline anymore — it’s no longer just plasma physics and radiation,” he says. “We’re trying to make a power plant now, and it’s an all hands-on-deck kind of thing, involving policy and economics and other subjects.”

      Although many are just getting started on their academic journeys, FUSar students believe this year will give them a strong push toward potential energy careers. “Fusion is the future of the energy transition and how we’re going to defeat climate change,” says Aurora. “I joined the program for a deep dive into the field, to help me decide whether I should invest the rest of my life to it.” More

    • 63 Shares159 Views

      in Energy

      Embracing the future we need

      by

      When you picture MIT doctoral students taking small PhD courses together, you probably don’t imagine them going on class field trips. But it does happen, sometimes, and one of those trips changed Andy Sun’s career.

      Today, Sun is a faculty member at the MIT Sloan School of Management and a leading global expert on integrating renewable energy into the electric grid. Back in 2007, Sun was an operations research PhD candidate with a diversified academic background: He had studied electrical engineering, quantum computing, and analog computing but was still searching for a doctoral research subject involving energy. 

      One day, as part of a graduate energy class taught by visiting professor Ignacio J. Pérez Arriaga, the students visited the headquarters of ISO-New England, the organization that operates New England’s entire power grid and wholesale electricity market. Suddenly, it hit Sun. His understanding of engineering, used to design and optimize computing systems, could be applied to the grid as a whole, with all its connections, circuitry, and need for efficiency. 

      “The power grids in the U.S. continent are composed of two major interconnections, the Western Interconnection, the Eastern Interconnection, and one minor interconnection, the Texas grid,” Sun says. “Within each interconnection, the power grid is one big machine, essentially. It’s connected by tens of thousands of miles of transmission lines, thousands of generators, and consumers, and if anything is not synchronized, the system may collapse. It’s one of the most complicated engineering systems.”

      And just like that, Sun had a subject he was motivated to pursue. “That’s how I got into this field,” he says. “Taking a field trip.”Sun has barely looked back. He has published dozens of papers about optimizing the flow of intermittent renewable energy through the electricity grid, a major practical issue for grid operators, while also thinking broadly about the future form of the grid and the process of making almost all energy renewable. Sun, who in 2022 rejoined MIT as the Iberdrola-Avangrid Associate Professor in Electric Power Systems, and is also an associate professor of operations research, emphasizes the urgency of rapidly switching to renewables.

      “The decarbonization of our energy system is fundamental,” Sun says. “It will change a lot of things because it has to. We don’t have much time to get there. Two decades, three decades is the window in which we have to get a lot of things done. If you think about how much money will need to be invested, it’s not actually that much. We should embrace this future that we have to get to.”

      Successful operations

      Unexpected as it may have been, Sun’s journey toward being an electricity grid expert was informed by all the stages of his higher education. Sun grew up in China, and received his BA in electronic engineering from Tsinghua University in Beijing, in 2003. He then moved to MIT, joining the Media Lab as a graduate student. Sun intended to study quantum computing but instead began working on analog computer circuit design for Professor Neil Gershenfeld, another person whose worldview influenced Sun.  

      “He had this vision about how optimization is very important in things,” Sun says. “I had never heard of optimization before.” 

      To learn more about it, Sun started taking MIT courses in operations research. “I really enjoyed it, especially the nonlinear optimization course taught by Robert Freund in the Operations Research Center,” he recalls. 

      Sun enjoyed it so much that after a while, he joined MIT’s PhD program in operations research, thanks to the guidance of Freund. Later, he started working with MIT Sloan Professor Dimitri Bertsimas, a leading figure in the field. Still, Sun hadn’t quite nailed down what he wanted to focus on within operations research. Thinking of Sun’s engineering skills, Bertsimas suggested that Sun look for a research topic related to energy. 

      “He wasn’t an expert in energy at that time, but he knew that there are important problems there and encouraged me to go ahead and learn,” Sun says. 

      So it was that Sun found himself in ISO-New England headquarters one day in 2007, finally knowing what he wanted to study, and quickly finding opportunities to start learning from the organization’s experts on electricity markets. By 2011, Sun had finished his MIT PhD dissertation. Based in part on ISO-New England data, the thesis presented new modeling to more efficiently integrate renewable energy into the grid; built some new modeling tools grid operators could use; and developed a way to add fair short-term energy auctions to an efficient grid system.

      The core problem Sun deals with is that, unlike some other sources of electricity, renewables tend to be intermittent, generating power in an uneven pattern over time. That’s not an insurmountable problem for grid operators, but it does require some new approaches. Many of the papers Sun has written focus on precisely how to increasingly draw upon intermittent energy sources while ensuring that the grid’s current level of functionality remains intact. This is also the focus of his 2021 book, co-authored with Antonio J. Conejo, “Robust Optimiziation in Electric Energy Systems.”

      “A major theme of my research is how to achieve the integration of renewables and still operate the system reliably,” Sun says. “You have to keep the balance of supply and demand. This requires many time scales of operation from multidecade planning, to monthly or annual maintenance, to daily operations, down through second-by-second. I work on problems in all these timescales.”

      “I sit in the interface between power engineering and operations research,” Sun says. “I’m not a power engineer, but I sit in this boundary, and I keep the problems in optimization as my motivation.”

      Culture shift

      Sun’s presence on the MIT campus represents a homecoming of sorts. After receiving his doctorate from MIT, Sun spent a year as a postdoc at IBM’s Thomas J. Watson Research Center, then joined the faculty at Georgia Tech, where he remained for a decade. He returned to the Institute in January of 2022.

      “I’m just very excited about the opportunity of being back at MIT,” Sun says. “The MIT Energy Initiative is a such a vibrant place, where many people come together to work on energy. I sit in Sloan, but one very strong point of MIT is there are not many barriers, institutionally. I really look forward to working with colleagues from engineering, Sloan, everywhere, moving forward. We’re moving in the right direction, with a lot of people coming together to break the traditional academic boundaries.” 

      Still, Sun warns that some people may be underestimating the severity of the challenge ahead and the need to implement changes right now. The assets in power grids have long life time, lasting multiple decades. That means investment decisions made now could affect how much clean power is being used a generation from now. 

      “We’re talking about a short timeline, for changing something as huge as how a society fundamentally powers itself with energy,” Sun says. “A lot of that must come from the technology we have today. Renewables are becoming much better and cheaper, so their use has to go up.”

      And that means more people need to work on issues of how to deploy and integrate renewables into everyday life, in the electric grid, transportation, and more. Sun hopes people will increasingly recognize energy as a huge growth area for research and applied work. For instance, when MIT President Sally Kornbluth gave her inaugural address on May 1 this year, she emphasized tackling the climate crisis as her highest priority, something Sun noticed and applauded. 

      “I think the most important thing is the culture,” Sun says. “Bring climate up to the front, and create the platform to encourage people to come together and work on this issue.” More

    • 150 Shares159 Views

      in Environment

      3 Questions: Boosting concrete’s ability to serve as a natural “carbon sink”

      by

      Damian Stefaniuk is a postdoc at the MIT Concrete Sustainability Hub (CSHub). He works with MIT professors Franz-Josef Ulm and Admir Masic of the MIT Department of Civil and Environmental Engineering (CEE) to investigate multifunctional concrete. Here, he provides an overview of carbonation in cement-based products, a brief explanation of why understanding carbonation in the life cycle of cement products is key for assessing their environmental impact, and an update on current research to bolster the process.

      Q: What is carbonation and why is it important for thinking about concrete from a life-cycle perspective?

      A: Carbonation is the reaction between carbon dioxide (CO2) and certain compounds in cement-based products, occurring during their use phase and end of life. It forms calcium carbonate (CaCO3) and has important implications for neutralizing the GHG [greenhouse gas] emissions and achieving carbon neutrality in the life cycle of concrete.

      Firstly, carbonation causes cement-based products to act as natural carbon sinks, sequestering CO2 from the air and storing it permanently. This helps mitigate the carbon emissions associated with the production of cement, reducing their overall carbon footprint.

      Secondly, carbonation affects concrete properties. Early-stage carbonation may increase the compressive strength of cement-based products, enhancing their durability and structural performance. However, late-stage carbonation can impact corrosion resistance in steel-reinforced concrete due to reduced alkalinity.

      Considering carbonation in the life cycle of cement-based products is crucial for accurately assessing their environmental impact. Understanding and leveraging carbonation can help industry reduce carbon emissions and maximize carbon sequestration potential. Paying close attention to it in the design process aids in creating durable and corrosion-resistant structures, contributing to longevity and overall sustainability.

      Q: What are some ongoing global efforts to force carbonation?

      A: Some ongoing efforts to force carbonation in concrete involve artificially increasing the amount of CO2 gas present during the early-stage hydration of concrete. This process, known as forced carbonation, aims to accelerate the carbonation reaction and its associated benefits.

      Forced carbonation is typically applied to precast concrete elements that are produced in artificially CO2-rich environments. By exposing fresh concrete to higher concentrations of CO2 during curing, the carbonation process can be expedited, resulting in potential improvements in strength, reduced water absorption, improved resistance to chloride permeability, and improved performance during freeze-thaw. At the same time, it can be difficult to quantify how much CO2 is absorbed and released because of the process.

      These efforts to induce early-stage carbonation through forced carbonation represent the industry’s focus on optimizing concrete performance and environmental impacts. By exploring methods to enhance the carbonation process, researchers and practitioners seek to more efficiently harness its benefits, such as increasing strength and sequestering CO2.

      It is important to note that forced carbonation requires careful implementation and monitoring to ensure desired outcomes. The specific procedures and conditions vary based on the application and intended goals, highlighting the need for expertise and controlled environments.

      Overall, ongoing efforts in forced carbonation contribute to the continuous development of concrete technology, aiming to improve its properties and reduce its carbon footprint throughout the life cycle of the material.

      Q: What is chemically-induced pre-cure carbonation, and what implications does it have?

      A: Chemically-induced pre-cure carbonation (CIPCC) is a method developed by the MIT CSHub to mineralize and permanently store CO2 in cement. Unlike traditional forced carbonation methods, CIPCC introduces CO2 into the concrete mix as a solid powder, specifically sodium bicarbonate. This approach addresses some of the limitations of current carbon capture and utilization technologies.

      The implications of CIPCC are significant. Firstly, it offers convenience for cast-in-place applications, making it easier to incorporate CO2 use in concrete projects. Unlike some other approaches, CIPCC allows for precise control over the quantity of CO2 sequestered in the concrete. This ensures accurate carbonation and facilitates better management of the storage process. CIPCC also builds on previous research regarding amorphous hydration phases, providing an additional mechanism for CO2 sequestration in cement-based products. These phases carbonate through CIPCC, contributing to the overall carbon sequestration capacity of the material.

      Furthermore, early-stage pre-cure carbonation shows promise as a pathway for concrete to permanently sequester a controlled and precise quantity of CO2. Our recent paper in PNAS Nexus suggests that it could theoretically offset at least 40 percent of the calcination emissions associated with cement production, when anticipating advances in the lower-emissions production of sodium bicarbonate. We also found that up to 15 percent of cement (by weight) could be substituted with sodium bicarbonate without compromising the mechanical performance of a given mix. Further research is needed to evaluate long-term effects of this process to explore the potential life-cycle savings and impacts of carbonation.

      CIPCC offers not only environmental benefits by reducing carbon emissions, but also practical advantages. The early-stage strength increase observed in real-world applications could expedite construction timelines by allowing concrete to reach its full strength faster.

      Overall, CIPCC demonstrates the potential for more efficient and controlled CO2 sequestration in concrete. It represents an important development in concrete sustainability, emphasizing the need for further research and considering the material’s life-cycle impacts.

      This research was carried out by MIT CSHub, which is sponsored by the Concrete Advancement Foundation and the Portland Cement Association. More