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      in Environment

      Global warming begets more warming, new paleoclimate study finds

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      It is increasingly clear that the prolonged drought conditions, record-breaking heat, sustained wildfires, and frequent, more extreme storms experienced in recent years are a direct result of rising global temperatures brought on by humans’ addition of carbon dioxide to the atmosphere. And a new MIT study on extreme climate events in Earth’s ancient history suggests that today’s planet may become more volatile as it continues to warm.

      The study, appearing today in Science Advances, examines the paleoclimate record of the last 66 million years, during the Cenozoic era, which began shortly after the extinction of the dinosaurs. The scientists found that during this period, fluctuations in the Earth’s climate experienced a surprising “warming bias.” In other words, there were far more warming events — periods of prolonged global warming, lasting thousands to tens of thousands of years — than cooling events. What’s more, warming events tended to be more extreme, with greater shifts in temperature, than cooling events.

      The researchers say a possible explanation for this warming bias may lie in a “multiplier effect,” whereby a modest degree of warming — for instance from volcanoes releasing carbon dioxide into the atmosphere — naturally speeds up certain biological and chemical processes that enhance these fluctuations, leading, on average, to still more warming.

      Interestingly, the team observed that this warming bias disappeared about 5 million years ago, around the time when ice sheets started forming in the Northern Hemisphere. It’s unclear what effect the ice has had on the Earth’s response to climate shifts. But as today’s Arctic ice recedes, the new study suggests that a multiplier effect may kick back in, and the result may be a further amplification of human-induced global warming.

      “The Northern Hemisphere’s ice sheets are shrinking, and could potentially disappear as a long-term consequence of human actions” says the study’s lead author Constantin Arnscheidt, a graduate student in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “Our research suggests that this may make the Earth’s climate fundamentally more susceptible to extreme, long-term global warming events such as those seen in the geologic past.”

      Arnscheidt’s study co-author is Daniel Rothman, professor of geophysics at MIT, and  co-founder and co-director of MIT’s Lorenz Center.

      A volatile push

      For their analysis, the team consulted large databases of sediments containing deep-sea benthic foraminifera — single-celled organisms that have been around for hundreds of millions of years and whose hard shells are preserved in sediments. The composition of these shells is affected by the ocean temperatures as organisms are growing; the shells are therefore considered a reliable proxy for the Earth’s ancient temperatures.

      For decades, scientists have analyzed the composition of these shells, collected from all over the world and dated to various time periods, to track how the Earth’s temperature has fluctuated over millions of years. 

      “When using these data to study extreme climate events, most studies have focused on individual large spikes in temperature, typically of a few degrees Celsius warming,” Arnscheidt says. “Instead, we tried to look at the overall statistics and consider all the fluctuations involved, rather than picking out the big ones.”

      The team first carried out a statistical analysis of the data and observed that, over the last 66 million years, the distribution of global temperature fluctuations didn’t resemble a standard bell curve, with symmetric tails representing an equal probability of extreme warm and extreme cool fluctuations. Instead, the curve was noticeably lopsided, skewed toward more warm than cool events. The curve also exhibited a noticeably longer tail, representing warm events that were more extreme, or of higher temperature, than the most extreme cold events.

      “This indicates there’s some sort of amplification relative to what you would otherwise have expected,” Arnscheidt says. “Everything’s pointing to something fundamental that’s causing this push, or bias toward warming events.”

      “It’s fair to say that the Earth system becomes more volatile, in a warming sense,” Rothman adds.

      A warming multiplier

      The team wondered whether this warming bias might have been a result of “multiplicative noise” in the climate-carbon cycle. Scientists have long understood that higher temperatures, up to a point, tend to speed up biological and chemical processes. Because the carbon cycle, which is a key driver of long-term climate fluctuations, is itself composed of such processes, increases in temperature may lead to larger fluctuations, biasing the system towards extreme warming events.

      In mathematics, there exists a set of equations that describes such general amplifying, or multiplicative effects. The researchers applied this multiplicative theory to their analysis to see whether the equations could predict the asymmetrical distribution, including the degree of its skew and the length of its tails.

      In the end, they found that the data, and the observed bias toward warming, could be explained by the multiplicative theory. In other words, it’s very likely that, over the last 66 million years, periods of modest warming were on average further enhanced by multiplier effects, such as the response of biological and chemical processes that further warmed the planet.

      As part of the study, the researchers also looked at the correlation between past warming events and changes in Earth’s orbit. Over hundreds of thousands of years, Earth’s orbit around the sun regularly becomes more or less elliptical. But scientists have wondered why many past warming events appeared to coincide with these changes, and why these events feature outsized warming compared with what the change in Earth’s orbit could have wrought on its own.

      So, Arnscheidt and Rothman incorporated the Earth’s orbital changes into the multiplicative model and their analysis of Earth’s temperature changes, and found that multiplier effects could predictably amplify, on average, the modest temperature rises due to changes in Earth’s orbit.

      “Climate warms and cools in synchrony with orbital changes, but the orbital cycles themselves would predict only modest changes in climate,” Rothman says. “But if we consider a multiplicative model, then modest warming, paired with this multiplier effect, can result in extreme events that tend to occur at the same time as these orbital changes.”

      “Humans are forcing the system in a new way,” Arnscheidt adds. “And this study is showing that, when we increase temperature, we’re likely going to interact with these natural, amplifying effects.”

      This research was supported, in part, by MIT’s School of Science. More

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      in Energy

      Electrifying cars and light trucks to meet Paris climate goals

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      On Aug. 5, the White House announced that it seeks to ensure that 50 percent of all new passenger vehicles sold in the United States by 2030 are powered by electricity. The purpose of this target is to enable the U.S to remain competitive with China in the growing electric vehicle (EV) market and meet its international climate commitments. Setting ambitious EV sales targets and transitioning to zero-carbon power sources in the United States and other nations could lead to significant reductions in carbon dioxide and other greenhouse gas emissions in the transportation sector and move the world closer to achieving the Paris Agreement’s long-term goal of keeping global warming well below 2 degrees Celsius relative to preindustrial levels.

      At this time, electrification of the transportation sector is occurring primarily in private light-duty vehicles (LDVs). In 2020, the global EV fleet exceeded 10 million, but that’s a tiny fraction of the cars and light trucks on the road. How much of the LDV fleet will need to go electric to keep the Paris climate goal in play? 

      To help answer that question, researchers at the MIT Joint Program on the Science and Policy of Global Change and MIT Energy Initiative have assessed the potential impacts of global efforts to reduce carbon dioxide emissions on the evolution of LDV fleets over the next three decades.

      Using an enhanced version of the multi-region, multi-sector MIT Economic Projection and Policy Analysis (EPPA) model that includes a representation of the household transportation sector, they projected changes for the 2020-50 period in LDV fleet composition, carbon dioxide emissions, and related impacts for 18 different regions. Projections were generated under four increasingly ambitious climate mitigation scenarios: a “Reference” scenario based on current market trends and fuel efficiency policies, a “Paris Forever” scenario in which current Paris Agreement commitments (Nationally Determined Contributions, or NDCs) are maintained but not strengthened after 2030, a “Paris to 2 C” scenario in which decarbonization actions are enhanced to be consistent with capping global warming at 2 C, and an “Accelerated Actions” scenario the caps global warming at 1.5 C through much more aggressive emissions targets than the current NDCs.

      Based on projections spanning the first three scenarios, the researchers found that the global EV fleet will likely grow to about 95-105 million EVs by 2030, and 585-823 million EVs by 2050. In the Accelerated Actions scenario, global EV stock reaches more than 200 million vehicles in 2030, and more than 1 billion in 2050, accounting for two-thirds of the global LDV fleet. The research team also determined that EV uptake will likely grow but vary across regions over the 30-year study time frame, with China, the United States, and Europe remaining the largest markets. Finally, the researchers found that while EVs play a role in reducing oil use, a more substantial reduction in oil consumption comes from economy-wide carbon pricing. The results appear in a study in the journal Economics of Energy & Environmental Policy.

      “Our study shows that EVs can contribute significantly to reducing global carbon emissions at a manageable cost,” says MIT Joint Program Deputy Director and MIT Energy Initiative Senior Research Scientist Sergey Paltsev, the lead author. “We hope that our findings will help decision-makers to design efficient pathways to reduce emissions.”  

      To boost the EV share of the global LDV fleet, the study’s co-authors recommend more ambitious policies to mitigate climate change and decarbonize the electric grid. They also envision an “integrated system approach” to transportation that emphasizes making internal combustion engine vehicles more efficient, a long-term shift to low- and net-zero carbon fuels, and systemic efficiency improvements through digitalization, smart pricing, and multi-modal integration. While the study focuses on EV deployment, the authors also stress for the need for investment in all possible decarbonization options related to transportation, including enhancing public transportation, avoiding urban sprawl through strategic land-use planning, and reducing the use of private motorized transport by mode switching to walking, biking, and mass transit.

      This research is an extension of the authors’ contribution to the MIT Mobility of the Future study. More

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      in Environment

      Finding common ground in Malden

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      When disparate groups convene around a common goal, exciting things can happen.

      That is the inspiring story unfolding in Malden, Massachusetts, a city of about 60,000 — nearly half people of color — where a new type of community coalition continues to gain momentum on its plan to build a climate-resilient waterfront park along its river. The Malden River Works (MRW) project, recipient of the inaugural Leventhal City Prize, is seeking to connect to a contiguous greenway network where neighboring cities already have visitors coming to their parks and enjoying recreational boating. More important, the MRW is changing the model for how cities address civic growth, community engagement, equitable climate resilience, and environmental justice.                                                                                        

      The MRW’s steering committee consists of eight resident leaders of color, a resident environmental advocate, and three city representatives. One of the committee’s primary responsibilities is providing direction to the MRW’s project team, which includes urban designers, watershed and climate resilience planners, and a community outreach specialist. MIT’s Kathleen Vandiver, director of the Community Outreach Education and Engagement Core at MIT’s Center for Environmental Health Sciences (CEHS), and Marie Law Adams MArch ’06, a lecturer in the School of Architecture and Planning’s Department of Urban Studies and Planning (DUSP), serve on the project team.

      “This governance structure is somewhat unusual,” says Adams. “More typical is having city government as the primary decision-maker. It is important that one of the first things our team did was build a steering committee that is the decision maker on this project.”

      Evan Spetrini ’18 is the senior planner and policy manager for the Malden Redevelopment Authority and sits on both the steering committee and project team. He says placing the decision-making power with the steering committee and building it to be representative of marginalized communities was intentional. 

      “Changing that paradigm of power and decision-making in planning processes was the way we approached social resilience,” says Spetrini. “We have always intended this project to be a model for future planning projects in Malden.”

      This model ushers in a new history chapter for a city founded in 1640.

      Located about six miles north of Boston, Malden was home to mills and factories that used the Malden River for power, and a site for industrial waste over the last two centuries. Decades after the city’s industrial decline, there is little to no public access to the river. Many residents were not even aware there was a river in their city. Before the project was under way, Vandiver initiated a collaborative effort to evaluate the quality of the river’s water. Working with the Mystic River Watershed Association, Gradient Corporation, and CEHS, water samples were tested and a risk analysis conducted.

      “Having the study done made it clear the public could safely enjoy boating on the water,” says Vandiver. “It was a breakthrough that allowed people to see the river as an amenity.”

      A team effort

      Marcia Manong had never seen the river, but the Malden resident was persuaded to join the steering committee with the promise the project would be inclusive and of value to the community. Manong has been involved with civic engagement most of her life in the United States and for 20 years in South Africa.

      “It wasn’t going to be a marginalized, token-ized engagement,” says Manong. “It was clear to me that they were looking for people that would actually be sitting at the table.”

      Manong agreed to recruit additional people of color to join the team. From the beginning, she says, language was a huge barrier, given that nearly half of Malden’s residents do not speak English at home. Finding the translation efforts at their public events to be inadequate, the steering committee directed more funds to be made available for translation in several languages when public meetings began being held over Zoom this past year.

      “It’s unusual for most cities to spend this money, but our population is so diverse that we require it,” says Manong. “We have to do it. If the steering committee wasn’t raising this issue with the rest of the team, perhaps this would be overlooked.”

      Another alteration the steering committee has made is how the project engages with the community. While public attendance at meetings had been successful before the pandemic, Manong says they are “constantly working” to reach new people. One method has been to request invitations to attend the virtual meetings of other organizations to keep them apprised of the project.

      “We’ve said that people feel most comfortable when they’re in their own surroundings, so why not go where the people are instead of trying to get them to where we are,” says Manong.

      Buoyed by the $100,000 grant from MIT’s Norman B. Leventhal Center for Advanced Urbanism (LCAU) in 2019, the project team worked with Malden’s Department of Public Works, which is located along the river, to redesign its site and buildings and to study how to create a flood-resistant public open space as well as an elevated greenway path, connecting with other neighboring cities’ paths. The park’s plans also call for 75 new trees to reduce urban heat island effect, open lawn for gathering, and a dock for boating on the river.

      “The storm water infrastructure in these cities is old and isn’t going to be able to keep up with increased precipitation,” says Adams. “We’re looking for ways to store as much water as possible on the DPW site so we can hold it and release it more gradually into the river to avoid flooding.”

      The project along the 2.3-mile-long river continues to receive attention. Recently, the city of Malden was awarded a 2021 Accelerating Climate Resilience Grant of more than $50,000 from the state’s Metropolitan Area Planning Council and the Barr Foundation to support the project. Last fall, the project was awarded a $150,015 Municipal Vulnerability Preparedness Action Grant. Both awards are being directed to fund engineering work to refine the project’s design.

      “We — and in general, the planning profession — are striving to create more community empowerment in decision-making as to what happens to their community,” says Spetrini. “Putting the power in the community ensures that it’s actually responding to the needs of the community.”

      Contagious enthusiasm

      Manong says she’s happy she got involved with the project and believes the new governance structure is making a difference.

      “This project is definitely engaging with communities of color in a manner that is transformative and that is looking to build a long-lasting power dynamic built on trust,” she says. “It’s a new energized civic engagement and we’re making that happen. It’s very exciting.”

      Spetrini finds the challenge of creating an open space that’s publicly accessible and alongside an active work site professionally compelling.

      “There is a way to preserve the industrial employment base while also giving the public greater access to this natural resource,” he says. “It has real implications for other communities to follow this type of model.”

      Despite the pandemic this past year, enthusiasm for the project is palpable. For Spetrini, a Malden resident, it’s building “the first significant piece of what has been envisioned as the Malden River Greenway.” Adams sees the total project as a way to build social resilience as well as garnering community interest in climate resilience. For Vandiver, it’s the implications for improved community access.

      “From a health standpoint, everybody has learned from Covid-19 that the health aspects of walking in nature are really restorative,” says Vandiver. “Creating greater green space gives more attention to health issues. These are seemingly small side benefits, but they’re huge for mental health benefits.”

      Leventhal City Prize’s next cycle

      The Leventhal City Prize was established by the LCAU to catalyze innovative, interdisciplinary urban design, and planning approaches worldwide to improve both the environment and the quality of life for residents. Support for the LCAU was provided by the Muriel and Norman B. Leventhal Family Foundation and the Sherry and Alan Leventhal Family Foundation.

      “We’re thrilled with inaugural recipients of the award and the extensive work they’ve undertaken that is being held up as an exemplary model for others to learn from,” says Sarah Williams, LCAU director and a professor in DUSP. “Their work reflects the prize’s intent. We look forward to catalyzing these types of collaborative partnership in the next prize cycle.”

      Submissions for the next cycle of the Leventhal City Prize will open in early 2022.    More

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      in Energy

      Cleaning up industrial filtration

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      If you wanted to get pasta out of a pot of water, would you boil off the water, or use a strainer? While home cooks would choose the strainer, many industries continue to use energy-intensive thermal methods of separating out liquids. In some cases, that’s because it’s difficult to make a filtration system for chemical separation, which requires pores small enough to separate atoms.

      In other cases, membranes exist to separate liquids, but they are made of fragile polymers, which can break down or gum up in industrial use.

      Via Separations, a startup that emerged from MIT in 2017, has set out to address these challenges with a membrane that is cost-effective and robust. Made of graphene oxide (a “cousin” of pencil lead), the membrane can reduce the amount of energy used in industrial separations by 90 percent, according to Shreya Dave PhD ’16, company co-founder and CEO.

      This is valuable because separation processes account for about 22 percent of all in-plant energy use in the United States, according to Oak Ridge National Laboratory. By making such processes significantly more efficient, Via Separations plans to both save energy and address the significant emissions produced by thermal processes. “Our goal is eliminating 500 megatons of carbon dioxide emissions by 2050,” Dave says.

      Play video

      What do our passions for pasta and decarbonizing the Earth have in common? MIT alumna Shreya Dave PhD ’16 explains how she and her team at Via Separations are building the equivalent of a pasta strainer to separate chemical compounds for industry.

      Via Separations began piloting its technology this year at a U.S. paper company and expects to deploy a full commercial system there in the spring of 2022. “Our vision is to help manufacturers slow carbon dioxide emissions next year,” Dave says.

      MITEI Seed Grant

      The story of Via Separations begins in 2012, when the MIT Energy Initiative (MITEI) awarded a Seed Fund grant to Professor Jeffrey Grossman, who is now the Morton and Claire Goulder and Family Professor in Environmental Systems and head of MIT’s Department of Materials Science and Engineering. Grossman was pursuing research into nanoporous membranes for water desalination. “We thought we could bring down the cost of desalination and improve access to clean water,” says Dave, who worked on the project as a graduate student in Grossman’s lab.

      There, she teamed up with Brent Keller PhD ’16, another Grossman graduate student and a 2016-17 ExxonMobil-MIT Energy Fellow, who was developing lab experiments to fabricate and test new materials. “We were early comrades in figuring out how to debug experiments or fix equipment,” says Keller, Via Separations’ co-founder and chief technology officer. “We were fast friends who spent a lot of time talking about science over burritos.”

      Dave went on to write her doctoral thesis on using graphene oxide for water desalination, but that turned out to be the wrong application of the technology from a business perspective, she says. “The cost of desalination doesn’t lie in the membrane materials,” she explains.

      So, after Dave and Keller graduated from MIT in 2016, they spent a lot of time talking to customers to learn more about the needs and opportunities for their new separation technology. This research led them to target the paper industry, because the environmental benefits of improving paper processing are enormous, Dave says. “The paper industry is particularly exciting because separation processes just in that industry account for more than 2 percent of U.S. energy consumption,” she says. “It’s a very concentrated, high-energy-use industry.”

      Most paper today is made by breaking down the chemical bonds in wood to create wood pulp, the primary ingredient of paper. This process generates a byproduct called black liquor, a toxic solution that was once simply dumped into waterways. To clean up this process, paper mills turned to boiling off the water from black liquor and recovering both water and chemicals for reuse in the pulping process. (Today, the most valuable way to use the liquor is as biomass feedstock to generate energy.) Via Separations plans to accomplish this same separation work by filtering black liquor through its graphene oxide membrane.

      “The advantage of graphene oxide is that it’s very robust,” Dave says. “It’s got carbon double bonds that hold together in a lot of environments, including at different pH levels and temperatures that are typically unfriendly to materials.”

      Such properties should also make the company’s membranes attractive to other industries that use membrane separation, Keller says, because today’s polymer membranes have drawbacks. “For most of the things we make — from plastics to paper and gasoline — those polymers will swell or react or degrade,” he says.

      Graphene oxide is significantly more durable, and Via Separations can customize the pores in the material to suit each industry’s application. “That’s our secret sauce,” Dave says, “modulating pore size while retaining robustness to operate in challenging environments.”

      “We’re building a catalog of products to serve different applications,” Keller says, noting that the next target market could be the food and beverage industry. “In that industry, instead of separating different corrosive paper chemicals from water, we’re trying to separate particular sugars and food ingredients from other things.”

      Future target customers include pharmaceutical companies, oil refineries, and semiconductor manufacturers, or even carbon capture businesses.

      Scaling up

      Dave, Keller, and Grossman launched Via Separations in 2017 — with a lot of help from MIT. After the seed grant, in 2015, the founders received a year of funding and support from the J-WAFS Solutions program to explore markets and to develop their business plans. The company’s first capital investment came from The Engine, a venture firm founded by MIT to support “tough tech” companies (tech businesses with transformative potential but long and challenging paths to success). They also received advice and support from MIT’s Deshpande Center for Technological Innovation, Venture Mentoring Service, and Technology Licensing Office. In addition, Grossman continues to serve the company as chief scientist.

      “We were incredibly fortunate to be starting a company in the MIT entrepreneurial ecosystem,” Keller says, noting that The Engine support alone “probably shaved years off our progress.”

      Already, Via Separations has grown to employ 17 people, while significantly scaling up its product. “Our customers are producing thousands of gallons per minute,” Keller explains. “To process that much liquid, we need huge areas of membrane.”

      Via Separations’ manufacturing process, which is now capable of making more than 10,000 square feet of membrane in one production run, is a key competitive advantage, Dave says. The company rolls 300-400 square feet of membrane into a module, and modules can be combined as needed to increase filtration capacity.

      The goal, Dave says, is to contribute to a more sustainable world by making an environmentally beneficial product that makes good business sense. “What we do is make manufacturing things more energy-efficient,” she says. “We allow a paper mill or chemical facility to make more product using less energy and with lower costs. So, there is a bottom-line benefit that’s significant on an industrial scale.”

      Keller says he shares Dave’s goal of building a more sustainable future. “Climate change and energy are central challenges of our time,” he says. “Working on something that has a chance to make a meaningful impact on something so important to everyone is really fulfilling.”

      This article appears in the Spring 2021 issue of Energy Futures, the magazine of the MIT Energy Initiative.  More

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      in Energy

      A material difference

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      Eesha Khare has always seen a world of matter. The daughter of a hardware engineer and a biologist, she has an insatiable interest in what substances — both synthetic and biological — have in common. Not surprisingly, that perspective led her to the study of materials.

      “I recognized early on that everything around me is a material,” she says. “How our phones respond to touches, how trees in nature to give us both structural wood and foldable paper, or how we are able to make high skyscrapers with steel and glass, it all comes down to the fundamentals: This is materials science and engineering.”

      As a rising fourth-year PhD student in the MIT Department of Materials Science and Engineering (DMSE), Khare now studies the metal-coordination bonds that allow mussels to bind to rocks along turbulent coastlines. But Khare’s scientific enthusiasm has also led to expansive interests from science policy to climate advocacy and entrepreneurship.

      A material world

      A Silicon Valley native, Khare recalls vividly how excited she was about science as a young girl, both at school and at myriad science fairs and high school laboratory internships. One such internship at the University of California at Santa Cruz introduced her to the study of nanomaterials, or materials that are smaller than a single human cell. The project piqued her interest in how research could lead to energy-storage applications, and she began to ponder the connections between materials, science policy, and the environment.

      As an undergraduate at Harvard University, Khare pursued a degree in engineering sciences and chemistry while also working at the Harvard Kennedy School Institute of Politics. There, she grew fascinated by environmental advocacy in the policy space, working for then-professor Gina McCarthy, who is currently serving in the Biden administration as the first-ever White House climate advisor.

      Following her academic explorations in college, Khare wanted to consider science in a new light before pursuing her doctorate in materials science and engineering. She deferred her program acceptance at MIT in order to attend Cambridge University in the U.K., where she earned a master’s degree in the history and philosophy of science. “Especially in a PhD program, it can often feel like your head is deep in the science as you push new research frontiers, but I wanted take a step back and be inspired by how scientists in the past made their discoveries,” she says.

      Her experience at Cambridge was both challenging and informative, but Khare quickly found that her mechanistic curiosity remained persistent — a realization that came in the form of a biological material.

      “My very first master’s research project was about environmental pollution indicators in the U.K., and I was looking specifically at lichen to understand the social and political reasons why they were adopted by the public as pollution indicators,” Khare explains. “But I found myself wondering more about how lichen can act as pollution indicators. And I found that to be quite similar for most of my research projects: I was more interested in how the technology or discovery actually worked.”

      Enthusiasm for innovation

      Fittingly, these bioindicators confirmed for her that studying materials at MIT was the right course. Now Khare works on a different organism altogether, conducting research on the metal-coordination chemical interactions of a biopolymer secreted by mussels.

      “Mussels secrete this thread and can adhere to ocean walls. So, when ocean waves come, mussels don’t get dislodged that easily,” Khare says. “This is partly because of how metal ions in this material bind to different amino acids in the protein. There’s no input from the mussel itself to control anything there; all the magic is in this biological material that is not only very sticky, but also doesn’t break very readily, and if you cut it, it can re-heal that interface as well! If we could better understand and replicate this biological material in our own world, we could have materials self-heal and never break and thus eliminate so much waste.”

      To study this natural material, Khare combines computational and experimental techniques, experimentally synthesizing her own biopolymers and studying their properties with in silico molecular dynamics. Her co-advisors — Markus Buehler, the Jerry McAfee Professor of Engineering in Civil and Environmental Engineering, and Niels Holten-Andersen, professor of materials science and engineering — have embraced this dual-approach to her project, as well as her abundant enthusiasm for innovation.

      Khare likes to take one exploratory course per semester, and a recent offering in the MIT Sloan School of Management inspired her to pursue entrepreneurship. These days she is spending much of her free time on a startup called Taxie, formed with fellow MIT students after taking the course 15.390 (New Enterprises). Taxie attempts to electrify the rideshare business by making electric rental cars available to rideshare drivers. Khare hopes this project will initiate some small first steps in making the ridesharing industry environmentally cleaner — and in democratizing access to electric vehicles for rideshare drivers, who often hail from lower-income or immigrant backgrounds.

      “There are a lot of goals thrown around for reducing emissions or helping our environment. But we are slowly getting physical things on the road, physical things to real people, and I like to think that we are helping to accelerate the electric transition,” Khare says. “These small steps are helpful for learning, at the very least, how we can make a transition to electric or to a cleaner industry.”

      Alongside her startup work, Khare has pursued a number of other extracurricular activities at MIT, including co-organizing her department’s Student Application Assistance Program and serving on DMSE’s Diversity, Equity, and Inclusion Council. Her varied interests also have led to a diverse group of friends, which suits her well, because she is a self-described “people-person.”

      In a year where maintaining connections has been more challenging than usual, Khare has focused on the positive, spending her spring semester with family in California and practicing Bharatanatyam, a form of Indian classical dance, over Zoom. As she looks to the future, Khare hopes to bring even more of her interests together, like materials science and climate.

      “I want to understand the energy and environmental sector at large to identify the most pressing technology gaps and how can I use my knowledge to contribute. My goal is to figure out where can I personally make a difference and where it can have a bigger impact to help our climate,” she says. “I like being outside of my comfort zone.” More

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      in Energy

      Reducing emissions by decarbonizing industry

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      A critical challenge in meeting the Paris Agreement’s long-term goal of keeping global warming well below 2 degrees Celsius is to vastly reduce carbon dioxide (CO2) and other greenhouse gas emissions generated by the most energy-intensive industries. According to a recent report by the International Energy Agency, these industries — cement, iron and steel, chemicals — account for about 20 percent of global CO2 emissions. Emissions from these industries are notoriously difficult to abate because, in addition to emissions associated with energy use, a significant portion of industrial emissions come from the process itself.

      For example, in the cement industry, about half the emissions come from the decomposition of limestone into lime and CO2. While a shift to zero-carbon energy sources such as solar or wind-powered electricity could lower CO2 emissions in the power sector, there are no easy substitutes for emissions-intensive industrial processes.

      Enter industrial carbon capture and storage (CCS). This technology, which extracts point-source carbon emissions and sequesters them underground, has the potential to remove up to 90-99 percent of CO2 emissions from an industrial facility, including both energy-related and process emissions. And that begs the question: Might CCS alone enable hard-to-abate industries to continue to grow while eliminating nearly all of the CO2 emissions they generate from the atmosphere?

      The answer is an unequivocal yes in a new study in the journal Applied Energy co-authored by researchers at the MIT Joint Program on the Science and Policy of Global Change, MIT Energy Initiative, and ExxonMobil.

      Using an enhanced version of the MIT Economic Projection and Policy Analysis (EPPA) model that represents different industrial CCS technology choices — and assuming that CCS is the only greenhouse gas emissions mitigation option available to hard-to-abate industries — the study assesses the long-term economic and environmental impacts of CCS deployment under a climate policy aimed at capping the rise in average global surface temperature at 2 C above preindustrial levels.

      The researchers find that absent industrial CCS deployment, the global costs of implementing the 2 C policy are higher by 12 percent in 2075 and 71 percent in 2100, relative to policy costs with CCS. They conclude that industrial CCS enables continued growth in the production and consumption of energy-intensive goods from hard-to-abate industries, along with dramatic reductions in the CO2 emissions they generate. Their projections show that as industrial CCS gains traction mid-century, this growth occurs globally as well as within geographical regions (primarily in China, Europe, and the United States) and the cement, iron and steel, and chemical sectors.

      “Because it can enable deep reductions in industrial emissions, industrial CCS is an essential mitigation option in the successful implementation of policies aligned with the Paris Agreement’s long-term climate targets,” says Sergey Paltsev, the study’s lead author and a deputy director of the MIT Joint Program and senior research scientist at the MIT Energy Initiative. “As the technology advances, our modeling approach offers decision-makers a pathway for projecting the deployment of industrial CCS across industries and regions.”

      But such advances will not take place without substantial, ongoing funding.

      “Sustained government policy support across decades will be needed if CCS is to realize its potential to promote the growth of energy-intensive industries and a stable climate,” says Howard Herzog, a co-author of the study and senior research engineer at the MIT Energy Initiative.

      The researchers also find that advanced CCS options such as cryogenic carbon capture (CCC), in which extracted CO2 is cooled to solid form using far less power than conventional coal- and gas-fired CCS technologies, could help expand the use of CCS in industrial settings through further production cost and emissions reductions.

      The study was supported by sponsors of the MIT Joint Program and by ExxonMobil through its membership in the MIT Energy Initiative. More