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MIT News | Climate Change & Sustainability

November 1, 2018

  • Mercury is an incredibly stubborn toxin. Once it is emitted from the smokestacks of coal-fired power plants, among other sources, the gas can drift through the atmosphere for up to a year before settling into oceans and lakes. It can then accumulate in fish as toxic methylmercury, and eventually harm the people who consume the fish.

    What’s more, mercury that was previously emitted can actually re-enter the atmosphere through evaporation. These “legacy emissions” can drift and be deposited elsewhere, setting off a cycle in which a growing pool of toxic mercury can circulate and contaminate the environment for decades or even centuries.

    A new MIT study finds that the longer countries wait to reduce mercury emissions, the more legacy emissions will accumulate in the environment, and the less effective any emissions-reducing policies will be when they are eventually implemented.

    In a paper published today in the journal Environmental Science and Technology, researchers have found that, for every five years that countries delay in cutting mercury emissions, the impact of any policy measures will be reduced by 14 percent on average. In other words, for every five years that countries wait to reduce mercury emissions, they will have to implement policies that are 14 percent more stringent in order to meet the same reduction goals.

    The researchers also found that remote regions are likely to suffer most from any delay in mercury controls. Mercury contamination in these regions will only increase, mostly from the buildup of legacy emissions that have traveled there and  continue to cycle through and contaminate their environments.

    “The overall message is that we need to take action quickly,” says study author Noelle Selin, associate professor in MIT’s Institute for Data Systems and Society and Department of Earth, Atmospheric, and Planetary Sciences. “We will be dealing with mercury for a long time, but we could be dealing with a lot more of it the longer we delay controls.”

    Global delay

    The Minamata Convention, an international treaty with 101 parties including the United States, went into effect in August 2017. The treaty represents a global commitment to protect human health and the environment by reducing emissions of mercury from anthropogenic sources. The treaty requires that countries control emissions from specific sources, such as coal-fired power plants, which account for about a quarter of the world’s mercury emissions. Other sources addressed by the treaty include mercury used in artisanal and small-scale gold mining, nonferrous metals production, and cement production.

    In drafting and evaluating their emissions-reducing plans, policymakers typically use models to simulate the amount of mercury that would remain in the atmosphere if certain measures were taken to reduce emissions at their source. But Selin says many of these models either do not account for legacy emissions or they assume that these emissions are constant from year to year. These measures also do not take effect immediately — the treaty urges that countries take action as soon as possible, but its requirements for controlling existing sources such as coal-fired power plants allow for up to a 10-year delay.  

    “What many models usually don’t take into account is that anthropogenic emissions are feeding future legacy emissions,” Selin says. “So today’s anthropogenic emissions are tomorrow’s legacy emissions.”

    The researchers suspected that, if countries hold off on implementing their emissions control plans, this could result in the growth of not just primary emissions from smokestacks, but also legacy emissions that made it back into the atmosphere a second time.

    “In real life, when countries say, ‘we want to reduce emissions,’ it usually takes many years before they actually do,” says Hélène Angot, the study’s first author and a former postdoc at MIT. “We wanted to ask, what are the consequences of delaying action when you take legacy emissions into account.”

    The legacy of waiting

    The group used a combination of two models: GEOS-Chem, a global atmospheric model developed at MIT that simulates the transport of chemicals in the atmosphere around the world; and a biogeochemical cycle model that simulates the way mercury circulates in compartments representing global atmosphere, soil, and water.

    With this modeling combination, the researchers estimated the amount of legacy emissions that would be produced in any region of the world, given various emissions-reducing policy timelines. They assumed a scenario in which countries would adopt a policy to reduce global mercury emissions by 50 percent compared to 2010 levels. They then simulated the amount of mercury that would be deposited in lakes and oceans, both from primary and legacy emissions, if such a policy were delayed every five years, from 2020 to 2050.

    In sum, they found that if countries were to delay by five, 10, or 15 years, any policy they would implement would have 14, 28, or 42 percent less of an impact, respectively, than if that same policy were put in place immediately.

    “The longer we wait, the longer it will take to get to safe levels of contamination,” Angot says.

    Remote consequences

    Based on their simulations, the researchers compared four regions located at various distances from anthropogenic sources: remote areas of eastern Maine; Ahmedabad, one of the largest cities in India, located near two coal-fired power plants; Shanghai, China’s biggest city, which has elevated atmospheric mercury concentrations; and an area of the Southern Pacific known for its tuna fisheries.

    They found that, proportionally, delays in mercury action had higher consequences in the regions that were farthest away from any anthropogenic source of mercury, such as eastern Maine — an area that is home to several Native American tribes whose livelihoods and culture depend in part on the local fish catches.

    Selin and Angot have been collaborating with members of these tribes, in a partnership that was established by MIT’s Center for Environmental Health Sciences.

    “These communities are trying to go back to a more traditional way of life, and they want to eat more fish, but they’re contaminated,” Angot says. “So they asked us, ‘When can we safely eat as much fish as we want? When can we assume that mercury concentrations will be low enough so we can eat fish regularly?’”

    To answer these questions, the team modeled the amount of fish contamination in eastern Maine that could arise from a buildup of legacy emissions if mercury-reducing policies are delayed. The researchers used a simple lake model, adapted and applied at MIT in collaboration with colleagues at Michigan Technological University, that simulates the way mercury circulates through a column that represents layers of the atmosphere, a lake, and the sediment beneath. The model also simulates the way mercury converts into methylmercury, its more toxic form that can bioaccumulate in fish.

    “In general, we found that the longer we wait to decrease global emissions, the longer it will take to get to safe methylmercury concentrations in fish,” Angot says. “Basically, if you are far away [from any anthropogenic source of mercury], you rely on everyone else. All countries have to decrease emissions if you want to see a decrease in contamination in a very remote place. So that’s why we need global action.”

    This research was supported, in part, by the National Institute of Environmental Health Sciences, through a core grant to MIT’s Center for Environmental Health Sciences, and by the NIEHS Superfund Basic Research Program.

October 29, 2018

  • A new system devised by MIT engineers could provide a low-cost source of drinking water for parched cities around the world while also cutting power plant operating costs.

    About 39 percent of all the fresh water withdrawn from rivers, lakes, and reservoirs in the U.S. is earmarked for the cooling needs of electric power plants that use fossil fuels or nuclear power, and much of that water ends up floating away in clouds of vapor. But the new MIT system could potentially save a substantial fraction of that lost water — and could even become a significant source of clean, safe drinking water for coastal cities where seawater is used to cool local power plants.

    The principle behind the new concept is deceptively simple: When air that’s rich in fog is zapped with a beam of electrically charged particles, known as ions, water droplets become electrically charged and thus can be drawn toward a mesh of wires, similar to a window screen, placed in their path. The droplets then collect on that mesh, drain down into a collecting pan, and can be reused in the power plant or sent to a city’s water supply system.

    The system, which is the basis for a startup company called Infinite Cooling that last month won MIT’s $100K Entrepreneurship Competition, is described in a paper published today in the journal Science Advances, co-authored by Maher Damak PhD ’18 and associate professor of mechanical engineering Kripa Varanasi. Damak and Varanasi are among the co-founders of the startup, and their research is supported in part by the Tata Center for Technology and Design.

    Varanasi’s vision was to develop highly efficient water recovery systems by capturing water droplets from both natural fog and plumes of industrial cooling towers. The project began as part of Damak’s doctoral thesis, which aimed to improve the efficiency of fog-harvesting systems that are used in many water-scarce coastal regions as a source of potable water. Those systems, which generally consist of some kind of plastic or metal mesh hung vertically in the path of fogbanks that regularly roll in from the sea, are extremely inefficient, capturing only about 1 to 3 percent of the water droplets that pass through them. Varanasi and Damak wondered if there was a way to make the mesh catch more of the droplets — and found a very simple and effective way of doing so.

    The reason for the inefficiency of existing systems became apparent in the team’s detailed lab experiments: The problem is in the aerodynamics of the system. As a stream of air passes an obstacle, such as the wires in these mesh fog-catching screens, the airflow naturally deviates around the obstacle, much as air flowing around an airplane wing separates into streams that pass above and below the wing structure. These deviating airstreams carry droplets that were heading toward the wire off to the side, unless they were headed bang-on toward the wire’s center.

    The result is that the fraction of droplets captured is far lower than the fraction of the collection area occupied by the wires, because droplets are being swept aside from wires that lie in front of them. Just making the wires bigger or the spaces in the mesh smaller tends to be counterproductive because it hampers the overall airflow, resulting in a net decrease in collection.

    But when the incoming fog gets zapped first with an ion beam, the opposite effect happens. Not only do all of the droplets that are in the path of the wires land on them, even droplets that were aiming for the holes in the mesh get pulled toward the wires. This system can thus capture a much larger fraction of the droplets passing through. As such, it could dramatically improve the efficiency of fog-catching systems, and at a surprisingly low cost. The equipment is simple, and the amount of power required is minimal.

    Next, the team focused on capturing water from the plumes of power plant cooling towers. There, the stream of water vapor is much more concentrated than any naturally occurring fog, and that makes the system even more efficient. And since capturing evaporated water is in itself a distillation process, the water captured is pure, even if the cooling water is salty or contaminated. At this point, Karim Khalil, another graduate student from Varanasi’s lab joined the team.

    “It’s distilled water, which is of higher quality, that’s now just wasted,” says Varanasi. “That’s what we’re trying to capture.” The water could be piped to a city’s drinking water system, or used in processes that require pure water, such as in a power plant’s boilers, as opposed to being used in its cooling system where water quality doesn’t matter much.

    A typical 600-megawatt power plant, Varanasi says, could capture 150 million gallons of water a year, representing a value of millions of dollars. This represents about 20 to 30 percent of the water lost from cooling towers. With further refinements, the system may be able to capture even more of the output, he says.

    What’s more, since power plants are already in place along many arid coastlines, and many of them are cooled with seawater, this provides a very simple way to provide water desalination services at a tiny fraction of the cost of building a standalone desalination plant. Damak and Varanasi estimate that the installation cost of such a conversion would be about one-third that of a building a new desalination plant, and its operating costs would be about 1/50. The payback time for installing such a system would be about two years, Varanasi says, and it would have essentially no environmental footprint, adding nothing to that of the original plant.

    “This can be a great solution to address the global water crisis,” Varanasi says. “It could offset the need for about 70 percent of new desalination plant installations in the next decade.”

    In a series of dramatic proof-of-concept experiments, Damak, Khalil, and Varanasi demonstrated the concept by building a small lab version of a stack emitting a plume of water droplets, similar to those seen on actual power plant cooling towers, and placed their ion beam and mesh screen on it. In video of the experiment, a thick plume of fog droplets is seen rising from the device — and almost instantly disappears as soon as the system is switched on.

    The team is currently building a full-scale test version of their system to be placed on the cooling tower of MIT’s Central Utility Plant, a natural-gas cogeneration power plant that provides most of the campus’ electricity, heating, and cooling. The setup is expected to be in place by the end of the summer and will undergo testing in the fall. The tests will include trying different variations of the mesh and its supporting structure, Damak says.

    That should provide the needed evidence to enable power plant operators, who tend to be conservative in their technology choices, to adopt the system. Because power plants have decades-long operating lifetimes, their operators tend to “be very risk-averse” and want to know “has this been done somewhere else?” Varanasi says. The campus power plant tests will not only “de-risk” the technology, but will also help the MIT campus improve its water footprint, he says. “This can have a high impact on water use on campus.”

  • Chien Wang, senior research scientist with the MIT Joint Program on the Science and Policy of Global Change, is one of six U.S.-based scientists selected this month to participate in French President Emmanuel Macron's "Make our Planet Great Again" program, an initiative aimed at boosting the international science community’s efforts to combat climate change. Chosen by an international panel of experts, the six new U.S-based scientists and eight others from around the world will join the program’s first 18 invitees, bringing the total number of participants to 32. 

    Launched in response to U.S. President Donald Trump’s June 2017 announcement of his intention to withdraw the U.S. from the 2015 Paris Agreement on climate change, and subsequently coordinated with a similar effort in Germany, the initiative provides up to 1.5 million euros (about $1.8 million) over three to five years for non-resident researchers to develop, along with French partners, high-level research projects in France that are aligned with the goals of the Paris Agreement.

    Projects will focus on advancing the world’s understanding of Earth system science, addressing sustainable development challenges and supporting the transition from fossil fuels to zero-carbon energy sources. The six new U.S.-based grant recipients — who hail from Carnegie Mellon University, Duke University, Florida State University, MIT, the University of Montana, and Yale University — will explore topics ranging from global ocean circulation to biodiversity.

    The objective of Wang’s project, “Enhancing the Understanding of the Roles of Aerosols in Climate and Environment (EUROACE),” is to advance knowledge about the critical, yet still poorly understood, issue of how aerosol-cloud interactions impact the climate, and to develop new methods to more precisely represent key physical processes involved in these interactions in Earth system models.

    Produced by power plant emissions, vehicle exhaust, biomass burning, and other human activities, as well by natural processes such as volcanic eruptions, airborne particulates, and aerosols have far-reaching effects on the Earth system.

    “Aerosols are critical components of the atmosphere that can reduce incoming solar radiation — and hence lower global surface temperatures — either directly by reflecting it skyward or indirectly by increasing the reflectivity of clouds,” says Wang, an expert on aerosol-cloud interactions who is also affiliated with the Department of Earth, Atmospheric and Planetary Sciences and the Center for Global Change Science. “Aerosols are also a major source of particulate pollution. A better understanding of the roles of aerosols in the climate and environment could provide decision-makers with more precise tools to monitor and mitigate climate change and air pollution.”

    Aerosol-cloud interactions are among the greatest sources of uncertainty in today’s climate model projections. To get a better handle on these interactions and their impacts on the global climate and environment, Wang will study their effects on precipitation (both locally and over great distances), cloud cover, and phase changes, and other critical atmospheric phenomena. He will also seek to determine the sensitivity of these effects to aerosol size, chemical composition, and atmospheric concentration — quantities that vary depending on the emissions source.

    To obtain this knowledge, Wang will employ regional-to-global-scale modeling with detailed physical and chemical processes alongside observational data and advanced data science tools such as deep machine learning algorithms.

    Starting this year, he will pursue this research in close collaboration with colleagues at two hosting research institutions in the city of Toulouse: the Laboratoire d’Aérologie of the Joint Research Unit of the National Research Council, and Paul Sabatier University.

  • Technology that uses light to clean water filtration systems in real time won the 2018 MADMEC competition on Oct. 9.

    The team that developed the system, Fiat Flux, received the $10,000 grand prize after five student teams presented their final results from the five-month materials science competition. Each team, made up entirely of current MIT students, spent the summer participating in mini-contests and feasibility studies that encouraged hands-on experimentation.

    Fiat Flux, which was also an MIT Clean Energy semifinalist this year, uses light to trigger a chemical reaction that combats the accumulation of dirt and other foulants in membrane-based water filtration systems. The foulants can lead to degradation, increased energy expenditures, high operating pressures, and other inefficiencies that can cut such systems’ productivity by more than half.

    “We’ve done interviews with people in the field and they all tell us the same thing: These [filtration] membranes never operate at the rate they are supposed to,” said Fiat Flux Chief Technology Officer Alvin Tan, who is pursuing a PhD in materials science and engineering at MIT.

    With roughly a third of the world’s population currently living in water-stressed regions, the solution offers a potential path to improving access to clean water.

    The Gryffindor team took home the second-place prize of $6,000 after its three members, all of whom are materials science graduate students, developed an inexpensive system for efficiently applying graphene to the surface of metal substrates to improve fatigue resistance. Using a custom electro-thermo-mechanical measurement system, the team showed that a copper wire coated in graphene exhibited less damage when exposed to cyclic stresses over time, compared to bare copper wires.

    “This is a huge problem, both with respect to wasted energy and wasted money,” Gryffindor team member Skylar Deckoff-Jones said of fatigue in systems such as wires, infrastructure, and aerospace and consumer products. “It’s estimated that roughly 4 percent of the U.S. GDP is used annually just to replace old components that degrade over time because of fatigue failure.”

    Boston Boron Company was awarded third place for its novel design of a system that leverages a process called molten oxide electrolysis (MOE) to produce boron. When compared to traditional processes, the company’s prototype produced boron for less than one-tenth the cost at a similar purity.

    The other two teams that presented were Technologies for Integrated Photonic Sensors, or TIPS, which developed a solution that addresses problems related to using integrated photonic chips in sensors; and HydroHome, which identified a mechanism for sustaining deep sea microorganisms in a laboratory setting.

    The teams gave oral and poster presentations to judges and attendees as the last step of the competition. MADMEC is a competition for student teams to develop and build technologies that use materials science to address problems of sustainability. Teams are provided with lab space, up to $1,000 in funding, and expert guidance to work through a series of developmental milestones and develop a prototype.

    “The real goal here is for students to do some prototyping, get their hands dirty, literally and figuratively, and learn how to drive a project,” Michael Tarkanian, a senior lecturer in Department of Materials Science and Engineering (DMSE) who runs MADMEC, said during opening remarks.

    MADMEC is hosted by DMSE and sponsored by Saint Gobain and the Dow Chemical Company. It is different from accelerators and startup competitions on campus in that it focuses on research and prototyping rather than developing business plans and starting a company. Tarkanian says that approach allows students to pursue ideas they may not think are immediately commercially viable.

    “[MADMEC’s] emphasis is on students getting experience with hands-on materials processing, and learning how to run their own research project,” Tarkanian explained.

    That said, since MADMEC’s founding in 2007, a number of participants have gone on to win larger competitions and start companies, including AquaFresco (the 2014 MADMEC winner), Embr (2013 winner) and Clear Motion (formerly Levant Power, third-place winner in 2007).

    The judges of this year’s competition were C. Cem Taşan, the Thomas B. King Career Development Professor of Metallurgy at MIT; Thomas Kalantar PhD ’90 of Dow Chemical; Nicholas Orf PhD ’09 of Saint Gobain; and Ockert Van Der Schijff of Exponent.

  • When they first met as graduate students in 2012, Samuel Shaner SM ’14, PhD ’18 and Mathew Ellis PhD ’17 realized they shared a common passion.

    “Sam was one year ahead of me, and as my official buddy during orientation weekend, he took me to the MIT Energy Conference,” recalls Ellis. “That first night, we began sharing ideas about what we wanted to see happen in the nuclear industry.”

    Adds Shaner: “We were both really interested in the innovative side of the industry and doing something entrepreneurial with nuclear reactor development.”

    The connection sparked at the start of their acquaintance is now generating dividends. In June, Yellowstone Energy, the company launched by the duo in 2016, received $2.6 million from the Department of Energy's Advanced Research Projects Agency-Energy (ARPA-E). This was one of just 10 awards distributed by a new ARPA-E program, Modeling-Enhanced Innovations Trailblazing Nuclear Energy Reinvigoration (MEITNER), which is intended to identify and develop novel technologies to advance safer and more cost-efficient nuclear reactors.

    “It was one of our best days, a really big moment for us,” says Ellis. “After working hard on the enabling technology, winning the grant through a selective and rigorous process was a great accomplishment.”

    Shaner says it was incredibly gratifying to receive “such significant validation of the idea we had come up with.”

    This idea, the culmination of several years of independent research by Shaner and Ellis, is a design for an advanced, modular nuclear reactor integrating a suite of commonsense but forward-thinking features. Yellowstone Energy’s reactor uses conventional, commercially available uranium dioxide fuel (UO2); operates at near-ambient pressure; and deploys a molten nitrate salt coolant that allows the reactor to reach higher operating temperatures than current water-cooled nuclear reactors. At the heart of this design lies a novel control device that is now under patent review, and in the first stages of testing at Oak Ridge National Laboratory.

    Shared frustration to shared vision

    Yellowstone Energy and its innovative approach was born out of “frustration with the policy, regulatory, and supply chain challenges of bringing new technologies to market,” says Shaner. “Just to make a small tweak, such as feeding more highly-enriched fuel to current reactors, involves tens of millions of dollars and many years,” he says.

    “Sam and I are a good mix of dreamers and pragmatists,” says Ellis. “We realized that a lot of advanced reactor concepts faced hurdles to get to market that went beyond nuclear physics, so we started thinking about how to fix that problem.”

    The pair set out to identify a set of reactor properties that would leapfrog the hurdles.

    “We needed to have a reactor design and technology that would be inexpensive to build and operate, and given the risks in building new reactors, a design that would promise a time- and capital-efficient pathway to market,” says Shaner.

    “We figured that the more we leveraged proven technology, the easier it would be to license the reactor,” says Ellis.

    Their first decision was to use what Shaner calls “off-the-shelf” fuel: UO2, the industry standard. But to increase operating efficiency with this fuel, they would need heat transfer fluids different from those circulating in current generation reactors. Other advanced reactor designs suggested fluoride and chloride salts, but these fluids prove technically challenging to engineer for reliable, commercial-scale systems. That led to another major design decision: to deploy molten nitrate salts, a high-temperature, ambient-pressure heat transfer fluid already in widespread use in the chemical and concentrated solar power industries.

    The challenge then came in bringing together the current fuel and the molten nitrate salt coolant, says Shaner. As graduate students working in Nuclear Science and Engineering with professors Ben Forget and Kord Smith, Ellis and Shaner had developed expertise in analyzing, modeling, and computing the physics of reactor systems. In a matter of months, they had devised a novel control device that would potentially enable their UO2 and molten-nitrate-salt-based reactor to function.

    A leg up for entrepreneurs

    In the fall of 2016, the team applied for and received a $25,000 grant from the MIT Sandbox Innovation Fund. With this money, they applied for intellctual property protection on their core enabling technology. But they also received valuable non-financial assistance.

    “MIT is one of the few places where big, ambitious ideas like a nuclear reactor startup are encouraged,” says Ellis. “The entrepreneurial ecosystem at MIT, specifically the mentoring through Sandbox, was a big inflection point for us, allowing us to get off the ground, move on with our idea, and ultimately make it a business.”

    Today, the team is based in Knoxville, Tennessee, working under the auspices of a Department of Energy incubator, and preparing a first round of simulations at the Oak Ridge Laboratory, with the help of nuclear industry and utility partners. Their collaboration has weathered well.

    “Sam and I are very aligned with what we want to do, and the impact we want to make, but we’re always willing to challenge each other to improve our ideas,” says Ellis. “We learned each other's abilities, strengths and quirks during five years together at MIT, which allows us to work really efficiently.”

    They've faced their share of challenges. “The hardest part has been the uncertainty, which can make things a roller coaster of emotions,” says Shaner. “For instance, when we finished grad school, we didn't know if we would get funding to continue working on our idea.”

    With the endorsement and financial backing of the Department of Energy, they are taking a moment to savor their accomplishment. But they never lose sight of the path before them.

    “Nuclear has a longer time horizon than most technologies, so we really have to believe in our mission — clean energy and reducing CO2 emissions — in order to get to the finish line,” says Ellis. “If we’re here a decade from now, it will be because people recognize our approach is fundamentally different, that our technology successfully reduced a lot of the risks, and that we can make a major impact in the near term on energy markets.”

  • MIT associate professor of metallurgy Antoine Allanore has received a $1.9 million grant from the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) to run larger scale tests of a new way to produce copper using electricity to separate copper from melted sulfur-based minerals, which are the main source of copper.

    One of Allanore's primary goals is to make high-purity copper that can go directly into production of copper wire, which is in increasing demand for applications from renewable energy to electric vehicles. Production of electric and hybrid cars and buses is expected to rise from 3.1 million vehicles in 2017 to 27.2 million by 2027, with an accompanying nine-fold increase in demand for copper from 204,000 metric tons to 1.9 million metric tons (2.09 million U.S. tons) over the same period, according to a March 2017 IDTechEx report commissioned by the International Copper Association (ICA).

    In June 2017, researchers in Allanore’s lab identified how to selectively separate pure copper and other metallic elements from sulfide mineral ore in one step. Their molten sulfide electrolysis process eliminates sulfur dioxide, a noxious byproduct of traditional copper extraction methods, instead producing pure elemental sulfur.

    “We think that with our technology we could provide these copper wires with less energy consumption and higher productivity,” Allanore says. It may be possible to cut the energy needed for making copper by 20 percent.

    In earlier research, postdoc Sulata K. Sahu and graduate student Brian J. Chmielowiec ’12, decomposed sulfur-rich minerals at high temperature into pure sulfur and extracted three different metals at very high purity: copper, molybdenum, and rhenium. The process is similar to the Hall-Héroult process, which uses electrolysis to produce aluminum, but operates at a higher operating temperature to enable production of liquid copper.

    Currently, it takes multiple steps to separate out copper, first crushing sulfide minerals, and then floating out the copper-bearing parts. This copper-rich material — copper concentrate — is next partially refined in a smelter, and further purified with electrolytic refining. “Professor Allanore’s approach would work on the copper concentrate and has the potential to produce copper rod in a single operation while separating unwanted impurities and recovering valuable byproducts that are also in the concentrate,” says Hal Stillman, director of technology development and transfer for the International Copper Association. “Professor Allanore’s approach is a big step; it allows a completely new approach to refining copper.”

    The three-year, $1.89 million DOE award will allow Allanore’s group to make a larger reactor, producing about 10 times as much liquid copper per hour, and to run the reactor for a longer time, enough to identify what happens to the other metals accompanying copper, which are also commercially important.

    Allanore’s group effort began this year, and he hopes it will provide the data needed to move on to a pilot plant within three years. “We are aiming to be ready to provide the design criteria, the material and operating conditions of a one metric ton per day demonstration reactor,” Allanore says. “If everything is successful, that’s what we will deliver.”

    Key technical challenges to overcome are proving the durability of the process over a longer time period and verifying the purity of the metals that are made in the process. Some of the byproducts of copper production, selenium, for example, are valuable in their own right.

    “The revolution that we are proposing is that only one reactor would do everything. It would make the liquid copper product and allow us to recover elemental sulfur, and allows us to recover selenium,” Allanore says. “We are using electricity, and electrons can be very selective, so we are using electrons in a manner that enables the most efficient separation of the products of the chemical process.”

    Conventional pyrometallurgy produces copper by burning the ore in air, requires four steps and produces noxious compounds like sulfur dioxide (SO2) that require secondary processing into sulfuric acid. The initial batch of copper also requires further processing. “It leaves behind copper metal with too much sulfur and too much oxygen, too much for downstream direct wire production,” Allanore says.

    Allanore lab’s new molten sulfide electrolysis method better handles trace metals and other impurities that come with the copper, allowing for separation of multiple elements at high purity from the same production process. “Therefore, we can rethink the manufacturing process of copper wires,” Allanore says.

    “The essential part is about providing the sector — mining companies, existing smelting companies and existing copper producers — some data that show what happens on longer operations and at a larger scale,” Allanore says.

    The International Copper Association conducted a Life Cycle Assessment that identified several areas where the copper industry can improve its environmental footprint. The study indicates the industry needs to continue reducing on-site sulfur dioxide emissions and to get its electricity from sources that are more environmentally friendly. Allanore’s project is relevant to both these issues. “If developed and deployed, it has the potential to decrease energy demand, operate entirely on renewable energy, and reduce sulfur dioxide emissions,” ICA technology director Stillman says. “In addition, it can separate unwanted impurities and recover valuable by-products from the concentrate. Right now, the technical evidence that is creating excitement is a small-scale proof-of-principle demonstration. It’s great that EERE has provided the needed initial funding to explore the potential. If the process works at larger scale, it could be the type of revolutionary approach that the industry is seeking.”

    Allanore’s award is one of 24 early-stage, innovative technology projects receiving up to $35 million in support. It was announced by the U.S. Office of Energy Efficiency and Renewable Energy Advanced Manufacturing Office earlier this year.

  • MIT’s Solar Electric Vehicle Team (SEVT) completed their first race in three years, the 2018 American Solar Challenge (ASC), last month. The team was awarded 5th place overall in the single-occupant vehicle class.

    The event was a series of competitions during which the team proved their exceptional talent and problem-solving abilities. In order to qualify for the American Solar Challenge, teams have to successfully complete various tests and races that fall under one of two categories: Scrutineering and the Formula Sun Grand Prix (FSGP).

    Scrutineering is a four-day process during which race officials test each car to confirm they are in line with challenge regulations. Included are electrical, dynamic, and mechanical tests. The team performed exceptionally well in electrical scrutineering. Mechanical scrutineering, however, brought some bumps in the road, mainly issues arising from the vehicle’s suspension system. The group did not let this setback bring them down, however.

    “The team was able to locate and debug each issue efficiently, collaboratively, and successfully,” noted MIT SEVT captain and junior Caroline Jordan.

    The group successfully passed all mechanical and dynamic tests on the fourth and final day of Scrutineering. Jordan recalled that — although it was a stressful time for the team — “we gained a lot of knowledge and grew as engineers and people.”

    Qualifying continued with the FSGP, a three-day track race held at the Motorsport Park Hastings in Hastings, Nebraska. Teams who successfully completed the race would be granted entrance to the American Solar Challenge.

    At the start of FSGP, an issue surfaced for the MIT SEVT: The tires on their vehicle were burning through. Instead of feeling discouraged, the team came together and inspected the car to find a solution. The following day, they were back in the game. The team drove 107 laps and received fourth place for single-occupant vehicles.

    “At this point, the car was doing amazingly and we qualified for ASC that day,” Jordan said.

    The ASC itself lasted nine days. This year's challenge was a 1762.7 mile race that followed the Oregon Trail from Omaha, Nebraska to Bend, Oregon.

    “Because of all of the fixes we had already identified, the car was very reliable going into the road race,” Jordan explains. The group performed well in spite of some small issues due to weather and race operations. MIT SEVT’s vehicle completed the race within their time limit using only solar power. The team received fifth place in the single-occupant vehicle class.

    Team member and sophomore Cece Chu notes that in spite of some technical difficulties, her team members kept her motivated throughout the competition.

    “The amount of planning, time, and effort that was put into the car during and leading up to the race was extraordinary, and the team had to display a lot of determination and sheer grit to get us through the qualifications,” she said. “My teammates are honestly the most hardworking and dedicated people I know, and seeing these qualities brought out firsthand during the race was incredibly motivating for me.”

    Jordan noted that the upcoming school year is set to be a big one for the MIT SEVT.

    “We will be entering a design year, during which we can pull from the vast amount of knowledge we gained during this race to use in the design process of our next car,” she explained. “It will be a very exciting time for the team.”

  • The Abdul Latif Jameel World Water and Food Security Lab (J-WAFS) has announced that two MIT PhD students, Krithika Ramchander and Andrea Beck, have been awarded fellowships to pursue water resource solutions for the 2018-2019 academic year. A third student, Julia Sokol, was chosen to receive an honorable mention. 

    This fall will mark the second year that J-WAFS has awarded fellowships to outstanding PhD candidates pursuing water sector research. The Rasikbhai L. Meswani Fellowship for Water Solutions and the J-WAFS Graduate Student Fellowship Program both give fellows one semester of funding as well as networking, mentorship, and opportunities to showcase their research. 

    The students were selected based on the quality and relevance of their research, as well as their demonstrated commitment to global as well as local challenges of water safety and water supply. The doctoral research topics the students are pursuing exemplify the wide range of approaches that J-WAFS supports across its various funding mechanisms. From the development of a novel, environmentally sustainable, and accessible water filter for rural communities in India, to a qualitative analysis of how to best strengthen a region’s public water and sanitation utilities, to engineering an innovative drip irrigation system designed to improve efficiency and reduce energy use, these research areas apply knowledge to the development of practical solutions that could be transformational for the communities that need them.

    Krithika Ramchander, who has been awarded the 2018-2019 Rasikbhai L. Meswani Fellowship for Water Solutions, is a PhD candidate in the Department of Mechanical Engineering and a past co-president of the MIT Water Club. The focus of Ramchander’s research is to develop a low-cost, point-of-use water filter using sapwood xylem from coniferous trees to facilitate safe access to drinking water for rural communities in India that lack access to safe water supplies. 

    Through research and field studies, she and others in Professor Rohit Karnik’s lab have shown how sapwood xylem could be repurposed into a water filter capable of meeting the drinking water requirement of an average household for nearly a week. The widespread availability of conifers in particular regions in India could allow for the manufacture of inexpensive, xylem-based filtration devices. If scaled up, this technology could support local economies across the globe as well as facilitate access to safe drinking water in regions that lack centralized water distribution systems. 

    The project, in collaboration with MIT D-Lab, has also been supported by two J-WAFS Solutions Grants in 2016 and 2017.

    The winner of the 2018-2019 J-WAFS Graduate Student Fellowship, Andrea Karin Beck, is a PhD candidate in the Department of Urban Studies and Planning. Beck is examining how transnational water operators’ partnerships (WOPs) could provide an alternative approach for strengthening public water and sanitation utilities in developing countries. 

    In contrast to public-private partnerships that are commonly used by water and sanitation utilities, WOPs are aimed at peer-to-peer capacity-building on a not-for-profit and solidarity basis.  To date, more than 200 WOPs have been formed around the world, predominantly between operators in the Global South. 

    Working with Professor Lawrence Susskind, Beck seeks to understand how different WOP constellations affect the everyday practices of water utility workers, and how these practices in turn mediate access to water and sanitation services among urban populations.

    J-WAFS has also awarded an honorable mention to Julia Sokol, a PhD candidate in the Department of Mechanical Engineering, who researches novel designs for drip irrigation emitters that operate at lower pressures and are more clog-resistant than currently-available products.

    Sokol is a student in Global Engineering and Research (GEAR) Lab run by Professor Amos Winter. Her research there involves experimentally validating and refining models of the drip emitters used for drip irrigation. A new clog-resistant design, if made commercially available, could help lower the capital, operating, and labor costs for farmers that use drip irrigation systems. She is currently collaborating with a manufacturing partner in India as well as field trial partners in the Middle East and North Africa to produce emitters according to this new design, test them on working farms, quantify their impact, and collect user feedback. 

  • The construction and operation of all kinds of buildings uses vast amounts of energy and natural resources. Researchers around the world have therefore been seeking ways to make buildings more efficient and less dependent on emissions-intensive materials.

    Now, a project developed through an MIT class has come up with a highly energy-efficient design for a large community building that uses one of the world’s oldest construction materials. For this structure, called “the Longhouse,” massive timbers made of conventional lumber would be laminated together like a kind of supersized plywood.

    The design will be presented this October at the Maine Mass Timber Conference, which is dedicated to exploring new uses of this material, which can be used to build safe, sound high-rise buildings, if building codes permit them.

    John Klein, a research scientist in MIT’s architecture department who taught a workshop called Mass Timber Design that came up with the new design, explains that “in North America, we have an abundance of forest resources, and a lot of it is overgrown. There’s an effort to find ways to use forest products sustainably, and the forests are actively undergoing thinning processes to prevent forest fires and beetle infestations.”

    People tend to think of wood as a suitable material for structures just a few stories high, but not for larger structures, Klein says. But already some builders are beginning to use mass timber products (a term that basically applies to any wood products much larger than conventional lumber) for bigger structures, including medium-rise buildings of up to 20 stories. Even taller buildings should ultimately be practical with this technology, he says. One of the largest mass timber buildings in the U.S. is the new 82,000-square-foot John W. Olver Design Building at the University of Massachusetts at Amherst.

    One of the first questions people raise when they hear of such construction has to do with fire. Can such tall wooden structures really be safe? In fact, Klein says, tests have demonstrated that mass timber structures can resist fire as well or better than steel. That’s because wood exposed to fire naturally produces a layer of char, which is highly insulating and can protect the bulk of the wood for more than two hours. Steel, in contrast, can fail suddenly when heat softens it and causes it to buckle.

    Klein explains that this natural fire resistance makes sense when you think about dropping a lit match onto a pile of wood shavings, versus dropping it onto a log. The shavings will burst into flames, but on the log a match will simply sputter out. The greater the bulk of the wood, the better it resists ignition.

    The structure designed by the class uses massive beams made from layers of wood veneers laminated together, a process known as laminated veneer lumber (LVL), made into panels 50 feet long, 10 feet wide, and more than 6 inches thick These are cut to size and used to make a series of large arches, 40 feet tall to the central peak and spanning 50 feet across, made of sections with a triangular cross-section to add structural strength. A series of these arches is assembled to create a large enclosed space with no need for internal structural supports. The pleated design of the roof is designed to accommodate solar panels and windows for natural lighting and passive solar heating.

    “The structural depth achieved by building up the triangular section helps us achieve the clear span desired for the communal space, all while lending a visual language on both the interior and the exterior of the structure,” says Demi Fang, an MIT architecture graduate student who was part of the design team. “Each arch tapers and widens along its length, because not every point along the arch will be subject to the same magnitude of forces, and this varying cross-section depth both expresses structural performance while encouraging materials savings,” she says.

    The arches would be factory-built in sections, and then bolted together on site to make the complete building. Because the building would be largely prefabricated, the actual on-site construction process would be greatly streamlined, Klein says.

    “The Longhouse is a multifunctional building, designed to accommodate a range of event scenarios from co-working, exercise classes, social mixers, exhibitions, dinner gatherings and lectures,” Klein says, adding that it builds on a long tradition of such communal structures in cultures around the world.  

    Whereas the production of concrete, used in most of the world’s large buildings, involves large releases of greenhouse gases from the baking of limestone, construction using mass timber has the opposite effect, Klein says. While concrete adds to the world’s burden of greenhouse gases, timber actually lessens it, because the carbon removed from the air while trees grow is essentially sequestered for as long as the building lasts. “The building is a carbon sink,” he says.

    One obstacle to greater use of mass timber for large structures is in current U.S. building codes, Klein says, which limit the use of structural wood to residential buildings up to five stories, or commercial buildings up to six stories. But recent construction of much taller timber buildings in Europe, Australia, and Canada — including an 18-story timber building in British Columbia — should help to establish such buildings’ safety and lead to the needed code changes, he says.

    Steve Marshall, an assistant director of cooperative forestry with the U.S. Forest Service, who was not involved in this project, says “Longhouse is a wonderfully creative and beautifully executed example of the design potential for mass timber.” He adds that “mass timber is poised to become a significant part of how America builds. The sustainability implications for the places we live, work, and play are huge. In addition to the well-known ramifications such as the sequestration of carbon within the buildings, there are also community benefits such as dramatically reduced truck traffic during the construction process.”

    The Longhouse design was developed by a cross-disciplinary team in 4.S13 (Mass Timber Design), a design workshop in MIT’s architecture department that explores the future of sustainable buildings. The team included John Fechtel, Paul Short, Demi Fang, Andrew Brose, Hyerin Lee, and Alexandre Beaudouin-Mackay. It was supported by the Department of Architecture, BuroHappold Engineering and Nova Concepts.

  • As a postdoc in the MIT Materials Systems Laboratory, Michele L. Bustamante works at the intersection of economics and materials science, creating models of supply and demand for raw materials important to high-tech, such as tellurium needed for thin-film solar cells and cobalt needed for lithium ion batteries.

    Her experience over the last two years helped Bustamante to win a one-year Congressional Science and Engineering Fellowship, which begins in September, from the Materials Research Society (MRS) and The Minerals, Metals and Materials Society (TMS).

    “I’ve worked with sponsors who are in the commodity industry, and they want to understand how are new things like renewable energy and electric and autonomous vehicles going to change demand for metals that they produce,” Bustamante explains. During her time at MIT, she has presented work at various conferences including the 2017 Materials Research Society Fall Meeting and a recent Industrial Liaison Program Summit at MIT. She collaborated with Materials Systems Laboratory Director Richard Roth, Principal Research Scientist Randolph E. Kirchain, and MSL Faculty Director Joel P. Clark, professor emeritus of materials systems.

    Working closely with Roth, Bustamante says, she learned how to look at an abstract problem and break it down. “Even if we are uncertain about pieces of it, we can add value to the conversation, we can create a tool that allows us to draw conclusions that have value despite uncertainty,” she says. Together, they created a high-level framework that has the power to answer questions about innovative technologies and material commodities at the same time. Nobody really knows how many autonomous cars will be on the road in 2050, she suggests. But the models they build can estimate the opportunity for commodity demand growth by looking at factors such as how well the technology functions, affordability, alternatives that can be substituted or competing technologies that provide same function, and how large the technology’s market is expected to grow.

    Surprising opportunity

    Bustamante’s work took a surprising turn when she explored the use of thinner and higher strength steels for Coast Guard and Navy ships at Huntington Ingalls Industries Shipbuilding Division in Pascagoula, Mississippi. The project, through the Lightweight Innovations for Tomorrow Initiative, took her to Mississippi many times, meeting on the ground with production crews. “This industry is as old as our country, and they are using a lot of lower tech manufacturing processes, because they are only making tens of ships of a certain class as opposed to the automotive industry where they are making millions each year,” Bustamante says.

    Newer steels that are stronger and can be used at thinner gauge respond differently to these legacy manufacturing processes and can result in extreme waviness when two of the flat metal plates are welded together. “When you’re building a ship that’s going to be used for the military, you want to make sure the quality is really safe and so you can’t have that,” she says.

    The MIT Materials Systems Lab was brought in for its expertise in understanding where economics and materials science meet. “Our role was to understand the manufacturing process, and use that to build a cost model to allow them to make this decision in an informed way. To understand, okay, it’s going to cost us X up front, but what kind of savings are we actually going to see down the line and is it something that we should be doing,” Bustamante explains. “That was a surprisingly fun project for me, and a great group of people that we got to work with. The kind of research that I’ve done [historically] has been very much in the lab on my computer, on the phone maybe with some other academics.”

    For her most recent project, Bustamante worked with Tanguy Marion, a student in the MIT Technology and Policy Program, on looking at different types of lithium ion batteries that are being used in electric vehicles. Marion went to China, where he interviewed battery and electric vehicle manufacturers to learn how they decide which lithium ion battery technology to use, comparing iron versus phosphorus, and cobalt versus nickel. The MIT team is creating a model to predict the outlook for adoption of different materials. Bustamante also traveled to China last July and September for this work.

    Communicating science

    Bustamante, who has a longstanding interest in communicating science, says she was excited to find out that there are career paths at the interface of science and policy. She participated in the Kaufman Teaching Certificate Program at MIT this spring.

    “The practice of teaching is inherently about communicating well and it’s about figuring out how to take something that I know and putting it in your head and getting you to understand it,” she says.

    “I see this as a really cool opportunity to get out of the lab and see what people who are making decisions for our country are doing, or not doing, with this scientific information that I spend day in and day out reading about and producing,” Bustamante says. “Can we as scientists do a better job of communicating what we we’re doing and the societal benefits that they provide, so that we can actually implement a lot more of all the cool stuff that’s going on at MIT and otherwise?”

    Smell of chocolate

    Bustamante, 28, grew up in Hackettstown, New Jersey, where the smell of chocolate hung in the air from the M&M Mars factory, especially around Halloween. “You smell chocolate in the air from my house; that was always really cool,” she says.

    After attending Warren Hills Regional High School, Bustamante went to Rensselaer Polytechnic Institute (RPI) in Troy, New York, where she completed her bachelor’s degree in environmental engineering and materials engineering in May 2012. “I have been someone who’s really interested in a lot of things and so I like to see what kind of opportunities present themselves and seize them when I can.”

    Fun little puzzle

    A summer undergraduate research opportunity at FREEDM Systems Center at North Carolina State University, challenged Bustamante to work on an electrical engineering project, helping to design a computer model for a rooftop solar panel array that she helped install. The model takes ambient conditions such as temperature, amount of solar radiation, and other outdoor conditions, and predicts expected solar panel output to aid in future research done with the array. “It was a fun little puzzle to actually implement that kind of a model, and it is not something I had ever done before, so I learned a ton,” Bustamante says.

    A presentation by a materials scientist from ARPA-E that summer gave Bustamante insight into the role materials science could play reducing environmental impact from the outset of a product’s life versus the traditional environmental engineering approach of focusing on remediation at the end of it. “I just remember being like, wow, this is it, this is what I have been looking for, and I was so interested. I saw materials science as this amazing opportunity to be on the front lines of products and things we put into the environment from the get go,” she says. Bustamante pursued a double major at RPI in materials science and environmental engineering. “I realized toward the end of it that it was my attempt to create a program that didn’t exist in sustainability by looking at … improving environmental quality of things being put out there at the beginning of a life cycle as well as reducing environmental harm at the end of a product life cycle. That sort of life cycle thinking is exactly what sustainability is about,” she says.

    Passion for sustainability

    Bustamante sought inspiration at the Golisano Institute for Sustainability at Rochester Institute of Technology. “They were doing precisely the kind of work I wanted to do that looked at the intersection of manufacturing and technology production, environmental impact reduction, and just the whole life cycle, looking at things big picture,” she says. Bustamante found a mentor in RIT Associate Professor of Sustainability Gabrielle G. Gaustad SM '09, PhD '09, who was a graduate student in the MIT Materials Systems Laboratory before embarking on her academic career. “She was someone who still to this day inspires me,”  says Bustamante, who was awarded her PhD at RIT in May 2016.

    Bustamante and Gaustad tackled the complex issue of tellurium supply and its effect on solar panel industry growth. Unlike copper, a primary metal mined and processed for its widespread demand and multiple uses from electrical wire to cookware coatings, tellurium is a relatively rare element and is produced as a byproduct of copper refining. That means the market for tellurium is somewhat dependent on the market for copper. If there isn’t enough of a commodity being produced, prices will go up, and, in most commodity markets, such as copper, those higher prices will spur miners and refiners to increase supply. “But my perspective of the byproduct research is that natural feedback mechanism is really muted if you are a byproduct, and so for those specific kind of markets, we do need to pay a little bit more attention if we value the products that they are being used in and see the benefit that they’re bringing,” Bustamante explains.

    “I did find that something that others hadn’t studied was when you mine copper, there is more than one way to do it, and only one of those ways actually yields this byproduct, tellurium. The other one does not,” she explains. The lower cost method, which is called solvent extraction and electrowinning (SX-EW), had been taking away some of the market share of production from the alternative method, called electrolytic refining, that does yield tellurium as a byproduct. “No one had really been looking at trends in the production [methods] of this main product and how that affects the availability of a byproduct,” Bustamante says. Understanding the details of supply and quantifying the scarcity of materials such as tellurium, which are critical to some new technologies, became the foundation of her research. From the perspective of risk, or criticality, three factors all must be considered: economic importance, supply security, and environmental impact, she says. Her dissertation work contributed to understanding each of these three factors.

    Addressing the latter component, Bustamante and her colleagues were motivated by the question, “Can we do a better job of understanding the environmental impact? Because that also is something that people factor into this measure of criticality.” She explored this question through work focused on highlighting challenges and sharing best practices for people performing life cycle assessments [LCAs] of solar energy technologies based on byproduct materials, like tellurium. Life cycle assessment, which is similar to carbon footprinting, is widely used to compare the environmental friendliness of products. It is done by detailing the activities in a product life cycle — how the necessary raw materials are produced, manufactured into products, transported, used, and ultimately disposed of — to quantify environmental impact drivers such as energy or water use and chemical emissions. This technique requires accurate modeling of how raw materials, like tellurium, are produced to describe their environmental impact. However, a key challenge of assessing life cycle impacts of a particular product is deciding how much impact should be assigned to an indivdidual step in a process, such as mining, when there are multiple steps in a production process. This challenge is known in the LCA community as “the allocation problem.” Bustamante’s work demonstrated the impact of ignoring uncertainties in the current approaches, which are based on mass or economic value of the products in a fixed time frame, and suggested guidelines for practitioners to minimize their impact in a standardized way. This work was published in Solar Energy Materials and Solar Cells.

    Considering supply security, Bustamante and Gaustad, along with fellow MSL alumna, Elisa Alonso PhD '09 developed a framework to compare the effectiveness of different solutions to criticality in a paper published last year in Environmental Science and Technology. For example, recovery of tellurium from recycling cadmium telluride solar panels could reduce supply risk. However, their work showed that this was not viable in the near future when criticality risks are likely to be highest because solar panels have an expected lifetime of about 25 years and most panels of this type were installed within the past decade. They also examined the effect of improving the percentage of tellurium successfully extracted from the mining process with promising results. Among these options, reducing demand by making solar material film thinner was shown to have the greatest benefit. Bustamante presented this work at the 2017 Materials Research Society Fall Meeting.

    “What the best solution would be is to start making these panels more efficient, which is great because that’s already their goal, the companies who make these. If we can make them more efficient, then we get more power out of less material and reduce that demand in the short term,” Bustamante suggests.

    Relative scarcity

    Much like tellurium, rare earth materials such as dysprosium and neodymium, which are used in high-strength magnets for electric vehicle motors, wind turbines and other clean energy technologies, face market supply issues since almost all of the world’s rare earths still come form China.

    “The more diversity we can get in the way those things are available, the less risk we face in price spikes for those, causing people not to be able to manufacture them and being too expensive to purchase, the technologies that are providing environmental benefit,” Bustamante says.

    Volunteer work

    In graduate school, Bustamante helped launch RIT’s Food Recovery Network chapter as one of its first volunteers. During the four years that she was involved, the chapter worked with the school’s food vendors to recover more than 50,000 pounds of food and distribute it to food banks and churches serving the needy in Rochester. “The goal of that organization is to try to both eliminate food waste on college campuses as well as to reduce food insecurity in the community,” she explains. “We do that by creating relationships with the dining centers on campus and getting them to work with us to save leftover food that they have.” One in five children in Rochester is food insecure, meaning they don’t have consistent access to food, and especially nutritious food, Bustamante says, citing a Community Health Needs Assessment. A U.S. Department of Agriculture report estimates that 31 percent of food at the retail and consumer levels goes uneaten.

    “It was a nice parallel to the research that I did because it had to do with an important material being supplied to society and being able to take a byproduct, something that was previously viewed as waste and being thrown away, and give it value and create a solution by just redefining what is actually waste and what is not waste,” Bustamante says. “It’s awesome when you can find opportunities that are such low hanging fruit for providing value,” says.

    Washington beckons

    For her fellowship application, Bustamante drafted a policy memo examining the impact of solar tariffs, such as the one put in place by the Trump Administration in January 2018. “The tariff supposedly has the goal of helping the solar industry by making it more expensive to import cells and panels, incentivizing you to purchase local, but there is no local manufacturing infrastructure, and it takes time to build that up,” Bustamante explains. She thinks it is unlikely to occur over the four years the tariff will be in place declining from 30 percent in the first year to 15 percent in the fourth. “Undoubtedly, it’s going to raise their prices, so people will have to pay more if they want solar installed for the next four years, and that’s, of course, going to tip the scale for some people and some people are not going to install that otherwise would have been interested in it. So, I think long term it’s going to have a pretty minor effect, but the guise of helping the solar industry by incentivizing manufacturing is really not what’s going to be the impact of this tariff.”

    Bustamante won’t learn until the fall which member of Congress or Congressional committee she will serve as a special legislative assistant. She’ll be joined in Washington by her husband, Justin Barends. After an orientation period, fellows are interviewed by Congressional offices to see where their skills and interest fit best. “Generally people end up in offices with people that they largely align with politically, which seems prudent,” Bustamante says. “I would like to work with someone who represents an area that I’ve lived in.”

    “I see my role as an opportunity to provide information and advocate for what the science is saying on a certain issue and trying to put that voice out there more, but at the end of the day I know that I’m not going to change politics. People are going to do what’s in their best interests. All I can to do is just keep trying and learning, and learning how that works and what people’s motivations are, so that I can do it better in the future,” Bustamante says.

    “I’m bringing my background and my network in the scientific community, but it’s also geared towards being a learning experience,” she says. “So if I can get anything at all accomplished that I feel really proud of, great. But I’m also going to be learning a lot through successes and failures, and hopefully that will lead to better success for the future.”

  • About 40 percent of all the energy consumed by buildings worldwide is used for space heating and cooling. With the warming climate as well as growing populations and rising standards of living — especially in hot, humid regions of the developing world — the level of cooling and dehumidification needed to ensure comfort and protect human health is predicted to rise precipitously, pushing up global energy demand.

    Much discussion is now focusing on replacing the greenhouse gases frequently used as refrigerants in today’s air conditioners. But another pressing concern is that most existing systems are extremely energy-inefficient.

    “The main reason they’re inefficient is that they have two tasks to perform,” says Leslie Norford, the George Macomber (1948) Professor in Construction Management in the Department of Architecture. “They need to lower temperature and remove moisture, and doing both those things together takes a lot of extra energy.”

    The standard approach to dehumidification is to run cold water through pipes inside a building space. If that water is colder than the dew-point temperature, water vapor in the air will condense on the outer surfaces of the pipes. (Think of water droplets beading up on a cold soda can on a hot, humid day.) In an air conditioning system, that water may drop off outside or, in a large-scale system serving a building, be gathered into a collection pan.

    The problem is that running a chiller to get water that cold takes a lot of electricity — and the water is far colder than needed to lower the temperature in the room. Separating the two functions brings energy savings on two fronts. Removing moisture from outdoor air brought into the building requires cold water but far less of it than is needed to remove heat from occupied areas. With that job done, running cool (not cold) water through pipes in the ceiling or floor will maintain a comfortable temperature.

    A decade ago, Norford and his colleagues at the Masdar Institute in Abu Dhabi confirmed the energy benefits of maintaining comfortable temperatures using cool-water pipes in the room — especially when indoor spaces are pre-cooled at night, when electricity is cheap and the outside air is cool. But the dehumidification process remained inefficient. Condensing water vapor is inherently energy-intensive, so the researchers needed to find another way to remove humidity.

    Borrowing from desalination systems

    Two years ago, a promising alternative was brought to Norford’s attention by John Lienhard, MIT’s Abdul Latif Jameel Professor of Water and Mechanical Engineering. Lienhard is Norford’s colleague at the Center for Environmental Sensing and Modeling, a research group at the Singapore-MIT Alliance for Research and Technology. Lienhard was working on energy-efficient technologies for desalination. Boiling seawater to precipitate the salt is very energy-intensive, so Lienhard’s group was looking instead at using semipermeable membranes that let water molecules through but stop salt ions. Norford thought a similar membrane could be designed that allows water vapor molecules to pass through so they can be separated from other, larger molecules that make up the indoor air.

    That concept became the subject of a project undertaken by two mechanical engineering graduate students: Tianyi Chen, who was working with Norford on the impacts of outdoor airflows on building energy performance, and Omar Labban, who was collaborating with Lienhard on using membranes in desalination systems. The students met in an advanced energy conversion class taught by Ahmed Ghoniem, the Ronald C. Crane (’72) Professor of Mechanical Engineering. Paired up for a class project, they identified air conditioning as a topic that would draw on their respective areas of research interest and use their newly acquired expertise in thermodynamic modeling and analysis.

    Their first task was to develop a thermodynamic model of the fundamental processes involved in air conditioning. Using that model, they calculated the theoretical least work needed to achieve dehumidification and cooling. They could then calculate the so-called second-law efficiency of a given technology, that is, the ratio of the theoretical minimum to its actual energy consumption. Using that metric as a benchmark, they could perform a systematic, consistent comparison of various designs in different climates.

    As an industrial benchmark for comparison, they used coefficient of performance (COP), a metric that shows how many units of cooling are provided for each unit of input electricity. The COP is used by today’s manufacturers, so it could show how different designs might perform relative to current equipment. For reference, Norford cites the COP of commercially available systems as ranging from 5 to 7. “But manufacturers are constantly coming up with better equipment, so the goalposts for competitors are continually moving,” he says.

    Norford’s earlier research had shown that cool-water pipes in the ceiling or floor can efficiently handle indoor cooling loads — that is, the heat coming from people, computers, sunlight, and so on. The researchers therefore focused on removing heat and moisture from outdoor air brought in for ventilation.

    They started by examining the performance of a commercially available air conditioner that uses the standard vapor compression system (VCS) that has been used for the past century. Their analysis quantified the inefficiency of not separating temperature and humidity control. Further, it pinpointed a major source of that inefficiency: the condensation process. Their results showed that the system was least efficient in cool, humid conditions and improved as conditions got hotter and drier. But at its best, it used five to 10 times more energy than the theoretical minimum required. Thus, there was significant opportunity for improvement.

    Membranes and desiccants

    To explore the use of membrane technology, the researchers began with a simple system incorporating a single membrane-containing unit. Outdoor air enters the unit, and a vacuum pump pulls the water vapor in it across the membrane. The pump then raises the pressure to ambient levels so the water vapor becomes liquid water before being ejected from the system. The no-longer-humid outdoor air passes from the membrane unit through a conventional cooling coil and enters the indoor space, providing fresh air for ventilation and pushing some warmer, humid exhaust air outdoors.

    According to their analysis, the system performs best in relatively dry conditions, but even then it achieves a COP of only 1.3 — not high enough to compete with a current system. The problem is that running the vacuum pump with high compression ratios consumes a lot of energy.

    To help cool the incoming air stream, the researchers tried adding a heat exchanger to transfer heat from the warm incoming air to the cool exhaust air and a condenser to turn water vapor captured by the membrane unit into cool water for the cooling coil. Those changes pushed the COP up to 2.4 — better but not high enough.

    The researchers next considered options using desiccants, materials that have a strong tendency to adsorb water and are often packed with consumer products to keep them dry. In air conditioning systems, a desiccant coating is typically mounted on a wheel that’s positioned between the incoming and exhaust airflows. As the wheel rotates, a portion of the desiccant first passes through the incoming air and adsorbs moisture from it. It then passes through the heated exhaust air, which dries it so it’s ready to adsorb more moisture on its next pass through the incoming air.

    The researchers began by analyzing several systems incorporating a desiccant wheel, but the gains in COP were limited. They next tried using the desiccant and membrane technologies together. In this design, a desiccant wheel, a membrane moisture exchanger, and a heat exchanger all transfer moisture and heat from the incoming air to the exhaust air. A cooling coil further cools the incoming air before it’s delivered to the indoor space. A heat pump warms the exhaust air, which then passes through the desiccant to dry and regenerate it for continued use.

    This complicated “hybrid” system yields a COP of 4 under a wide range of temperatures and humidity. But that’s still not high enough to compete.

    Two-membrane system

    The researchers then tried a novel system that omits the desiccant wheel but includes two membrane units, yielding a design that’s relatively simple but more speculative than the others. The key new concept involved the fate of the water vapor in the incoming air stream.

    In this system, a vacuum pump pulls the water vapor through a membrane—now called membrane unit 1. But the captured water vapor is then pushed across the membrane in unit 2 and joins the exhaust air stream — without ever turning into liquid water. In this arrangement, the vacuum pump only has to ensure that the vapor pressure is higher on the upstream side of membrane 2 than it is on the downstream side so that the water vapor is pushed through. There’s no need for raising the pressure to ambient levels, which would condense the water vapor, so running the vacuum pump takes less work. That novel approach results in a COP that can reach as high as 10 and achieves a COP of 9 at many combinations of temperature and humidity.

    Different options for different cities

    For most of the systems analyzed, performance varies at different combinations of ambient temperature and humidity level. To investigate the practical impact of that variability, the researchers examined how selected systems would perform in four cities with different climates. In each case, the analysis assumed an average summertime outdoor temperature and relative humidity.

    In general, the systems they considered outperformed the conventional VCS operating at COPs consistent with current practice. For example, in Dubai (representing a tropical desert climate), using the hybrid membrane-desiccant system could reduce energy consumption by as much as 30 percent relative to the standard VCS. In Las Vegas (a subtropical arid climate), where humidity is lower, a desiccant-based system (without the membrane) is the most efficient option, potentially also bringing a 30 percent reduction.

    In New York (a subtropical humid climate), all the designs look good, but the desiccant-based system does best with a 70 percent reduction in overall energy consumption. And in Singapore (a tropical oceanic climate), the desiccant system and the combined membrane-desiccant system do equally well, with a potential savings of as much as 40 percent — and given the costs of the two options, the desiccant-alone system emerges as the top choice.

    Taken together, the researchers’ findings provide two key messages for achieving more efficient indoor cooling worldwide. First, using membranes and desiccants can push up air conditioner efficiency, but the real performance gains come when such technologies are incorporated into carefully designed and integrated systems. And second, the local climate and the availability of resources — both energy and water — are critical factors to consider when deciding what air conditioning system will deliver the best performance in a given area of the world.

    This article appears in the Spring 2018 issue of Energy Futures, the magazine of the MIT Energy Initiative.

  • Most efforts to reduce the adverse air pollution and climate impacts of today’s vehicles focus on cars and light-duty trucks that are typically fueled by gasoline, with strategies that range from electrification and carpooling to autonomous vehicles.

    “These strategies can be an important part of the overall solution,” says Daniel Cohn, research scientist at the MIT Energy Initiative. “But it’s also increasingly important to think about heavy- and medium-duty trucks. Finding a way to clean them up could actually bring a greater improvement in worldwide air quality during the next few decades.”

    Powered largely by diesel engines, those trucks are now the largest producer of nitrogen oxide (NOx) emissions in the transportation sector, contributing to ground-level ozone, respiratory problems, and premature deaths in urban areas. Some estimates project that diesel fuel — used for both trucks and cars —will out-sell gasoline worldwide within the next decade, threatening to further increase already-severe urban air pollution as well as greenhouse gas (GHG) concentrations. 

    Today’s heavy-duty diesel engines provide fuel efficiency and high power, making them ideal for long-haul, high-mileage commercial vehicles. But finding another option is critical, says Cohn. “We need to replace diesel engines with other internal combustion engines that are much cleaner and produce less greenhouse gas.”

    Using computer simulation analysis, Cohn and his colleague Leslie Bromberg, principal research engineer at the Plasma Science and Fusion Center and the Sloan Automotive Laboratory, have designed a replacement half-sized gasoline-alcohol engine that should be not only cleaner but also lower-cost and higher-performing — and could be introduced into the fleet of vehicles on the road soon.

    Replacing the heavy-duty diesel

    Within the United States, pressure on the trucking industry to deal with diesel emissions has been mounting. Indeed, expected regulations in California would require that NOx emissions from medium- and heavy-duty trucks be cut by about 90 percent relative to today’s cleanest diesels, which use complex and expensive exhaust treatment systems just to meet current regulations. In some parts of the world, such as India and China, those cleanup systems aren’t generally used. As a result, NOx emissions are about 10 times higher, and getting them down to the level of future California regulations would require a reduction of about 98 percent.

    In the United States, some trucks have begun to meet the expected strict NOx limits using large spark-ignition (SI) engines fueled by natural gas. But large-scale adoption of those engines would be problematic. Storing and distributing a gaseous fuel raises vehicle cost and poses infrastructure challenges, and the use of natural gas can lead to a heightened climate impact because of the leakage of methane, a GHG with high global warming potential.

    To avoid the challenges of dealing with natural gas, Cohn and Bromberg decided to pursue another approach: a heavy-duty SI engine fueled instead by gasoline. In general, gasoline SI engines produce low NOx emissions. Guided by their computer models, Cohn and Bromberg took a series of steps to increase the power and efficiency of that design without sacrificing its emissions benefits.

    During normal gasoline SI engine operation, the process of translating the combustion of gases into torque (rotational force) at the wheels progresses smoothly — until there’s a need for high-torque operation, for example, to pull a heavy load at high speed or up a hill. Then, pressures and temperatures inside the cylinder can rise so much that the unburned combustion gases spontaneously ignite. The result is knock, which causes a metallic clanging noise and can damage the engine. The need to prevent knock has up to now limited improvements in efficiency and performance that would be needed for gasoline engines to compete with diesels.

    Cohn and Bromberg dealt with that problem using alcohol. When the SI engine is working hard and knock would otherwise occur, a small amount of ethanol or methanol is injected into the hot combustion chamber, where it quickly vaporizes, cooling the fuel and air and making spontaneous combustion much less likely. In addition, because of alcohol’s chemical composition, its inherent knock resistance is higher than that of gasoline. The alcohol can be stored in a small, separate fuel tank — as exhaust-cleanup fluid is stored in a diesel engine vehicle. Alternatively, it could be provided by onboard separation of alcohol from gasoline in the regular fuel tank. (Almost all gasoline sold in the United States is now a mix of 90 percent gasoline and 10 percent ethanol.)

    With concern about knock removed, the researchers were able to take full advantage of two techniques used in today’s passenger cars. First, they used turbocharging, but at higher levels. Turbocharging involves compressing the incoming air so that more molecules of air and fuel fit inside the cylinder. The result is that a given power output can be achieved using a smaller total cylinder volume. And second, they used a high compression ratio, which is the ratio of the volume of the combustion chamber before compression to the volume after. At a higher compression ratio, the burning gases expand more in each cycle, so more energy is delivered for a given amount of fuel.

    The researchers also made use of an important feature of the low-NOx heavy-duty SI engine fueled by natural gas: They assumed that the mixture of air and fuel inside their engine contained just enough air to burn up all the fuel — no more, no less. That stoichiometric operation permitted important changes not possible in the diesel, which must run with lots of extra air to control emissions. With stoichiometric operation, they could utilize a three-way catalyst to clean up the engine exhaust. A relatively inexpensive system, the three-way catalyst removes NOx, carbon monoxide, and unburned hydrocarbons from engine exhaust and is key to the low NOx achieved in today’s SI engines.

    Then, given stoichiometric operation combined with a higher level of turbocharging and a high compression ratio, the researchers were able to shrink their whole engine. The SI engine doesn’t contain all the excess air that’s in a diesel, so the total volume of its cylinders can be smaller.

    “Because of that difference, you can replace a diesel engine with an SI engine about half as big,” says Bromberg.

    With that reduction in size comes an increase in fuel efficiency. In any engine, the process of pumping air into the cylinders and various sources of friction inevitably reduce fuel efficiency. Those pumping losses depend on engine size. Make an engine smaller, and there’s less friction and less wasted fuel.

    Taken together, the low-cost three-way catalyst and smaller overall size help make the gasoline-alcohol engine less expensive than the cleanest diesel engine with a state-of-the-art exhaust-cleanup system. Indeed, according to the researchers’ estimates, the cost of the gasoline-alcohol engine plus its exhaust-treatment system would be roughly half that of the cleanest diesel engine.

    Power, efficiency, and alcohol use

    How does the half-sized gasoline-alcohol SI engine compare to today’s cleanest full-sized diesel on efficiency and power? To answer that question, the researchers used a series of sophisticated engine and vehicle simulations and chemical kinetic models developed by Bromberg.

    For the comparison, they used an illustrative version of their engine based on a 6.7-liter engine that’s now manufactured and could — with relatively small alterations — be converted to the gasoline-alcohol configuration. Their analysis assumed that the compression ratio and engine torque were about the same in the 6.7 gasoline-alcohol SI engine as in a 12-liter diesel engine. But the SI engine can run far faster than the diesel can. (Combustion is faster with spark ignition than with the compression ignition used in diesel engines.) Because of the faster operation and the roughly equivalent torque, the small engine can produce almost 50 percent more power than the diesel can. And while the gasoline-alcohol engine is somewhat more efficient than the diesel at high torque and less efficient at low torque, in general the small SI engine is about as efficient as the diesel.

    However, as more torque is required, knock becomes more likely, so more ethanol is needed. At the highest torque, about 80 percent of the total fuel must be ethanol to prevent knock. That estimate raises a concern: In the United States, ethanol is widely used in a low-concentration mixture with gasoline, but pure ethanol or a high-concentration ethanol-gasoline blend may not be available or may be too costly. So how much ethanol is likely to be required for a given trip? 

    As an example, the researchers considered a trip taken by a long-haul, heavy-duty vehicle that requires high torque most of the time. Depending on the compression ratio, ethanol could make up 20 to 40 percent of its total fuel consumption. In contrast, a delivery truck might operate at low torque most of the time and do just fine with ethanol as 10 percent of its total fuel over a driving period. 

    “Such levels of ethanol consumption are doable,” notes Cohn. “But the system would be more attractive to people if you had a case where you could use less ethanol.”

    One way to reduce ethanol use would be to dilute the ethanol with water. Using the knock model, Cohn and Bromberg determined that knock resistance is actually higher when water makes up as much as a third of the secondary fuel. “And in some cases where you don’t need any ethanol for antifreeze, you might be able to run with water alone as the secondary fluid,” says Cohn.

    Another approach to reducing alcohol use — called upspeeding — involves operating the engine at a higher speed. Running the engine faster and adjusting the gearing in the transmission to increase the ratio of engine rpm to wheel rpm make it possible to use less engine torque in the gasoline engine to achieve the same torque at the wheel as in the diesel. According to the researchers’ calculations, that reduction in engine torque could reduce ethanol use over a driving period to less than 10 percent of the total fuel consumed, an amount that could be supplied by onboard fuel separation. 

    Reducing climate impacts

    Cohn points out one more benefit of the gasoline-alcohol SI engine: a pathway to reducing GHG emissions.

    “A somewhat under-recognized aspect in evaluating the environmental impacts of transportation vehicles is that GHG emissions from trucks worldwide will overtake GHG emissions from cars sometime between 2020 and 2030,” he notes.

    The gasoline-alcohol SI engine can be operated in a flexible-fuel mode where it uses only pure alcohol if desired. Right now, looking at the life cycle of the fuels and assuming comparable engine efficiency, using ethanol produced from corn by state-of-the-art methods generates about 20 percent lower GHG emissions than using gasoline or diesel fuel. Even greater reductions in GHG emissions could come when ethanol and methanol fuels are produced from agricultural, forestry, and municipal waste or specialty biomass. 

    “Reducing GHG emissions from trucks by finding an alternative source of power — for example, through electrification — could take a long time,” says Cohn. “But if you can operate your engine partially with ethanol or entirely with ethanol, that’s a good way to make a start right away.”

    This research was supported by the Arthur Samberg Energy Innovation Fund of the MIT Energy Initiative.

    This article appears in the Spring 2018 issue of Energy Futures, the magazine of the MIT Energy Initiative.

October 19, 2018

  • Climate change, a surging population, and increasing demand for food, housing and natural resources present Africa and the world with extraordinary challenges.

    On Sept. 24, numerous experts from diverse disciplines and areas of the world convened at MIT to discuss sustainable development in Africa. The conference was hosted by the Université Mohammed VI Polytechnique-MIT Research Program (UMRP), a collaboration with the Moroccan university (UM6P) led by MIT faculty director Elfatih A. B. Eltahir, the Breene M. Kerr Professor of Hydrology and Climate in the Department of Civil and Environmental Engineering.

    UMRP, which launched in 2016, is comprised of six projects led by MIT faculty, which are each built around the dissertation research of an MIT graduate student. The UMRP researchers work closely with the faculty and student colleagues from UM6P, who engage in complementary research.

    The African Sustainability Conference provided a showcase for these projects, featuring presentations from MIT and UM6P faculty, researchers, and international experts on climate and water, sustainable urbanization, precision agriculture, smart chemistry, and industrial optimization for the phosphate industry. Group discussions related to critical challenges and potential opportunities within each area followed each session.

    Eltahir began the conference by highlighting the significance of Africa in terms of global sustainability, noting that the substantial yet uncertain effects of climate change are already noticeable in agricultural productivity and infrastructure throughout the continent. Projections show that by 2050, Africa’s population will double from 1 billion to 2 billion people, creating an influx of urbanization.

    “We are forging an honest collaboration between MIT and a like-minded research and education partner in Africa with the mission of advancing sustainability goals, while also helping build UM6P’s institutional capacity to lead by example on the continent,” expressed Eltahir.

    Eltahir brings his background in hydrology and climate to his own UMRP research project, that focuses on improving water management and agricultural productivity in one of Morocco’s major river basins, the Oum-Er-Rbia watershed.

    “Climate change is a major challenge for the world, especially concerning Africa. Morocco is a country that suffers from interannual rainfall variability. We are focused on looking for ways to improve management for water resources and availability,” explained Eltahir.

    Morocco is highly vulnerable to heat waves and low precipitation, and those extremes are expected to intensify due to climate change. Eltahir’s research addresses these issues through a three-level modeling approach geared toward climatology and forecasting, hydrology, and operations in terms of agricultural planning and infrastructure.

    He hopes the program will continue to grow, allowing for further collaboration between MIT and UM6P, students, and faculty. Furthermore, some of the tools, models, and processes that are being utilized in Morocco and greater Africa, can be applied to other regions around the world who will face similar challenges due to climate change.

    In addition to Eltahir, the workshop brought together MIT professors John Fernández of the Department of Architecture, Benedetto Marelli of the Department of Civil and Environmental Engineering, Paul Barton of the Department of Chemical Engineering, and Christopher Cummins and Yogesh Surendranath of the Department of Chemistry. Including UM6P colleagues, invited international experts, and MIT graduate students, the conference highlighted efforts to implement resilience, adaptability, and sustainability into the future of African cities.

    John Fernández, director of MIT’s Environmental Solutions Initiative and professor of architecture, helped launch UMRP with the focus that there is an urgency needed for long-term sustainability, in the areas of society, economy, and climate.

    Through comprehensive material accounting of the needs of Moroccan cities, Fernández will be developing specific technology and policy recommendations for UM6P, providing the country with a template for long term urban sustainability.

    “One of our goals is to produce a UMRP urban resource tool that would allow Morocco and greater Africa to access data and reach informed decisions about urban sustainability,” said Fernández. The tool’s engine would be developed in partnership with UM6P and the tool itself would be offered online.

    The strains of urban population growth, and a predicted threefold increase in urban energy and urban land area globally is a primary motivation of the project. In addition, it is likely that low-income urban areas in Africa will be most vulnerable to the consequences of climate change due to unreliable and limited access to energy sources, water, and shelter.

    “With climate change, what happens in terms of the vulnerability of lower income segments of urban population, and at what point, with extreme heat, intense precipitation or climate-induced water shortage does urban vulnerability become urban survivability?” Fernández asked.

    Securing resources for the future

    In addition to climate concerns, agricultural production concerns were raised as well from both MIT and UM6P experts.

    Benedetto Marelli, the Paul M Cook Career Development Assistant Professor in the Department of Civil and Environmental Engineering, shared that he is focused on developing new technologies that can increase agricultural production. He stated that with a growing population, a 70 percent increase in food production will be necessary by 2050.

    Marelli is in the process of creating biofertilizers that can work with the plant, to boost germination and overcome environmental stressors such as pests, disease, heat waves, and drought.

    Manal Mhada, a postdoc from UM6P, presented her research on precision agriculture, and the efficient use of seeds and fertilizers. Her work focuses on human-centered solutions for Moroccan communities, and includes local farmers in her research projects.

    Mhada conducts close studies of the crop quinoa, with the intention of introducing it to Morocco in order to provide food and nutritional security. She acknowledges that climate change threatens agriculture, food security, and peace, but emphasizes that “big problems allow for immense opportunity.”

    Resilience became a common thread throughout the conference. Hassan Radoine, director of the School of Architecture and Design at UM6P, urges for a paradigm shift, explaining how most people perceive Africa as poor.

    “What is resilience? The responsiveness to risk and inventing new solutions. The reconstructing of a community or a place, is resilience,” Radoine said.

    Echoing this, Remy Sietchiping, UN-Habitat leader of regional and metropolitan planning, outlined the urban agenda of creating smart cities that encompass adaptability and most importantly, resilience.

    “You cannot buy sustainability,” Randoine said.

    During the last session of the conference, gears shifted towards the “smart chemistry” projects, which work closely with Moroccan company, OCP, the leading supplier of phosphate rock in the world. Paul M Cook Career Development Assistant Professor Yogeth Surendranath of the MIT Department of Chemistry presented on the natural resource, phosphorous, which is abundant to Morocco.

    However, the process of creating phosphate products demands an incredible amount of energy. Surendranath’s research is targeted at elucidating the process of electrochemical phosphate reduction in molten salts, in order to lower economic and environmental costs, and advance Morocco in the chemical markets.

    Henry Dreyfus Professor of Chemistry Christopher Cummins’ project is also working with phosphate, and has successfully created a new method for the synthesis of phosphorous. The method utilizes a “wet process,” which enables the reduction of energy inputs, waste, and overall harm to the environment.

    Following Cummins, Professor Paul Barton of the Department of Chemistry, discussed his project on optimal industrial symbiosis for the Jorf Lasfar platform, the phosphate mineral processing facility in Morocco. Barton is studying ways to optimize the phosphate resource, to generate returns on investment while also being mindful of energy and water consumption.

    Throughout the afternoon, goals for the future were at the forefront of everyone’s mind. UMRP aims to continue to conduct impactful research, tackle developmental challenges, and build a strong foundation for UM6P.

    “This conference provided a wonderful platform for UMRP to showcase their projects, build a community with UM6P and other colleagues, and help the growing institutional commitment of MIT to engage fruitfully in a future of sustainable development for Africa,” said UMRP Executive Director Kurt Sternlof.

    It was evident that the MIT faculty-led research is results-driven and exhibits a strong vision of a sustainable future. The idea that UMRP research projects develop small solutions to make big impacts, became a recurring element of the conference.

    “Whether discussing urban metabolism, industrial symbiosis, chemical processing or the hydrological cycle, the common theme of recognizing and optimizing closed loops of resource use — circular economies of production, consumption and renewal — was clear and compelling, and therein beats the heart of sustainability,” Sternlof said.

October 17, 2018

  • The Beaufort Gyre is an enormous, 600-mile-wide pool of swirling cold, fresh water in the Arctic Ocean, just north of Alaska and Canada. In the winter, this current is covered by a thick cap of ice. Each summer, as the ice melts away, the exposed gyre gathers up sea ice and river runoff, and draws it down to create a huge reservoir of frigid fresh water, equal to the volume of all the Great Lakes combined.

    Scientists at MIT have now identified a key mechanism, which they call the “ice-ocean governor,” that controls how fast the Beaufort Gyre spins and how much fresh water it stores. In a paper published today in Geophysical Research Letters, the researchers report that the Arctic’s ice cover essentially sets a speed limit on the gyre’s spin.

    In the past two decades, as temperatures have risen globally, the Arctic’s summer ice has progressively shrunk in size. The team has observed that, with less ice available to control the Beaufort Gyre’s spin, the current has sped up in recent years, gathering up more sea ice and expanding in both volume and depth.

    If global temperatures continue to climb, the researchers expect that the mechanism governing the gyre’s spin will diminish. With no governor to limit its speed, the researchers say the gyre will likely transition into “a new regime” and eventually spill over, like an overflowing bathtub, releasing huge volumes of cold, fresh water into the North Atlantic, which could affect the global climate and ocean circulation.

    “This changing ice cover in the Arctic is changing the system which is driving the Beaufort Gyre, and changing its stability and intensity,” says Gianluca Meneghello, a research scientist in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “If all this fresh water is released, it will affect the circulation of the Atlantic.”

    Meneghello is a co-author of the paper, along with John Marshall, the Cecil and Ida Green Professor of Oceanography, Jean-Michel Campin and Edward Doddridge of MIT, and Mary-Louise Timmermans of Yale University.

    A “new Arctic ocean”

    There have been a handful of times in the recorded past when the Beaufort Gyre has spilled over, beginning with the Great Salinity Anomaly in the late 1960s, when the gyre sent a surge of cold, fresh water southward. Fresh water has the potential to dampen the ocean’s overturning circulation, affecting surface temperatures and perhaps storminess and climate.

    Similar events could transpire if the Arctic ice controlling the Beaufort Gyre’s spin continues to recede each year.

    “If this ice-ocean governor goes away, then we will end up with basically a new Arctic ocean,” Marshall says.

    “Nature has a natural governor”

    The researchers began looking into the dynamics of the Beaufort Gyre several years ago. At that time, they used measurements taken by satellites between 2003 and 2014, to track the movement of the Arctic ice cover, along with the speed of the Arctic wind. They used these measurements of ice and wind speed to estimate how fast the Beaufort Gyre must be downwelling, or spinning down beneath the ice. But the number they came up with was much smaller than what they expected.

    “We thought there was a coding error,” Marshall recalls. “But it turns out there was something else kicking back.” In other words, there must be some other mechanism that was limiting, or slowing down, the gyre’s spin.

    The team recalculated the gyre’s speed, this time by including estimates of ocean current activity in and around the gyre, which they inferred from satellite measurements of sea surface heights. The new estimate, Meneghello says, was “much more reasonable.”

    In this new paper, the researchers studied the interplay of ice, wind, and ocean currents in more depth, using a high-resolution, idealized representation of ocean circulation based on the MIT General Circulation Model, built by Marshall’s group. They used this model to simulate the seasonal activity of the Beaufort Gyre as the Arctic ice expands and recedes each year.

    They found that in the spring, as the Arctic ice melts away, the gyre is exposed to the wind, which acts to whip up the ocean current, causing it to spin faster and draw down more fresh water from the Arctic’s river runoff and melting ice. In the winter, as the Arctic ice sheet expands, the ice acts as a lid, shielding the gyre from the fast-moving winds. As a result, the gyre spins against the underside of the ice and eventually slows down.

    “The ice moves much slower than wind, and when the gyre reaches the velocity of the ice, at this point, there is no friction — they’re rotating together, and there’s nothing applying a stress [to speed up the gyre],” Meneghello says. “This is the mechanism that governs the gyre’s speed.”

    “In mechanical systems, the governor, or limiter, kicks in when things are going too fast,” Marshall adds. “We found nature has a natural governor in the Arctic.”

    The evolution of sea ice over the Beaufort Gyre: In springtime, as ice thaws and melts into the sea, the gyre is exposed to the Arctic winds. Courtesy of the researchers

    “In a warming world”

    Marshall and Meneghello note that, as Arctic temperatures have risen in the last two decades, and summertime ice has shrunk with each year, the speed of the Beaufort Gyre has increased. Its currents have become more variable and unpredictable, and are only slightly slowed by the return of ice in the winter.

    “At some point, if this trend continues, the gyre can’t swallow all this fresh water that it’s drawing down,” Marshall says. Eventually, the levee will likely break and the gyre will burst, releasing hundreds of billions of gallons of cold, fresh water into the North Atlantic.

    An increasingly unstable Beaufort Gyre could also disrupt the Arctic’s halocline — the layer of ocean water underlying the gyre’s cold freshwater, that insulates it from much deeper, warmer, and saltier water. If the halocline is somehow weakened by a more instable gyre, this could encourage warmer waters to rise up, further melting the Arctic ice.

    “This is part of what we’re seeing in a warming world,” Marshall says. “We know the global mean temperatures are going up, but the Arctic tempertures are going up even more. So the Arctic is very vulnerable to climate change. And we’re going to live through a period where the governor goes away, essentially.”

    This research was supported, in part, by the National Science Foundation.

October 16, 2018

  • “In order to do the kind and scale of work that we do, international collaboration is essential. However, this can be difficult to fund,” Chris Voigt said. “J-WAFS is providing the support that we need for the cross-institutional and cross-sector collaboration that is enabling our work to move forward.”

    Voigt, a professor in the MIT Department of Biological Engineering, made those comments at the first of two research workshops produced by the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) on Sept. 14th and Sept. 28th at the Samberg Center. The annual workshop brings members of the MIT community together to learn about the latest research results from J-WAFS-funded teams, to hear about newly funded projects, and to provide feedback on each other’s work.

    The specific collaboration Voigt was referring to is a project that connects the work  on prokaryotic gene clusters in his lab to research at the Max Planck Institute of Molecular Plant Physiology in Germany and the Center for Plant Biotechnology and Genomics at the Universidad Politécnica in Spain.  

    Voigt and experts in plastid engineering and plant gene expression from these partnering institutions are working to engineer cereal grains to produce their own nitrogen, eliminating the need for added fertilizer. Their goal is to transform farming at every scale — reducing the greenhouse gas emissions of industrial fertilizer production as well as problems of eutrophication from nutrient run-off and reducing the cost of added nitrogen fertilizer. With a growing world population and increasing demand for grain as a food and fuel, the need for innovations in agricultural technologies is urgent, yet the technical challenges are steep and often require complementary areas of expertise. Therefore, when researchers like Voightshare their skills and resources with other global experts in pursuit of a shared goal, the combined effort has the potential to produce dramatic results.

    The collaboration is a hallmark of MIT’s research culture. J-WAFS seeks to leverage that collaboration by being particularly welcoming of cross-disciplinary project proposals and research teams. In fact, the majority of J-WAFS current and concluding projects are led by two or more principal investigators, with many of those teams being cross-disciplinary.      

    In the case of a J-WAFS Solutions-funded project led by principal investigators Timothy Swager and Alexander Klibanov from the Department of Chemistry, interdisciplinary collaboration grew as the work on the project progressed. The team is developing a handheld food safety sensor that uses specialized droplets — called Janus emulsions — to test for bacterial contamination in food. The droplets behave like a dynamic lens, changing in the presence of specific bacteria. 

    In developing optical systems that can indicate the presence or absence of bacteria, including salmonella, by analyzing the light either transmitted through or emanating from these dynamic lenses, the researchers realized that they did not have the expertise to fully understand the optics they observed when the droplets were exposed to light. For that, they needed help. Swager reached out to Mathias Kolle, an assistant professor in the Department of Mechanical Engineering, whose expertise in optical materials proved to be key. 

    Kolle, who has received J-WAFS seed funding for his own work on industrial algae production, and his graduate student Sara Nagelberg provided the calculations necessary to understand the mechanics of light’s interaction with the particles. These insights contributed to sensor designs that were dramatically more effective, and the team has now launched a startup — Xibus Systems — and is currently working on product development. 

    “This is the beginning of a much longer story for us,” Swager commented, reflecting on his collaboration with Kolle’s lab.

    Several other research teams are applying multiple disciplinary perspectives to their work. 

    In one project, Evelyn Wang, the Gail E. Kendall Professor in the Department of Mechanical Engineering, has teamed up with Mircea Dincă, an associate professor in the Department of Chemistry, to engineer highly absorbent metal organic frameworks in a device that pulls drinking water from air.

    In another, assistant professor David Des Marais in the Department of Civil and Environmental Engineering is collaborating with Caroline Uhler, the Henry L. and Grace Doherty Assistant Professor in the Department of Electrical Engineering and Computer Science, to develop tools to analyze and understand the ways that genes regulate plants’ responses to environmental stressors such as drought. Their goal is to apply this understanding to better breed and engineer stress-tolerant plants so that crop yields can improve even as climate change creates more extreme growing conditions.

    Meanwhile, J-WAFS itself collaborated with a partner program in organizing the event. The second day of the workshop coincided with the Tata Center’s annual research symposium, which was also held at the Samberg Center. J-WAFS and Tata’s missions have some significant overlaps — many Tata-funded MIT projects address food, water, and agriculture challenges in the developing world. The two groups merged audiences for their afternoon sessions and presentations to take advantage of these synergies, enabling participants of each event to interact and to learn about the food and water innovations that the programs are supporting.      

    By funding research in all schools at MIT and seeding and supporting innovative collaboration that crosses departments and schools alikeJ-WAFS seeks to advance research that can provide answers to what might be one of the most pressing questions of our time: How do we ensure safe and resilient supplies of water and food on our changing planet, now and in the future? When experts come together around an urgent question like this one, each one approaches it from a different angle. And when successes emerge from collaborations in J-WAFS-funded projects, it demonstrate sthe value of MIT’s culture of interdisciplinary collaboration.    

September 4, 2018

  • How can the world achieve the deep carbon emissions reductions that are necessary to slow or reverse the impacts of climate change? The authors of a new MIT study say that unless nuclear energy is meaningfully incorporated into the global mix of low-carbon energy technologies, the challenge of climate change will be much more difficult and costly to solve. For nuclear energy to take its place as a major low-carbon energy source, however, issues of cost and policy need to be addressed.

    In "The Future of Nuclear Energy in a Carbon-Constrained World," released by the MIT Energy Initiative (MITEI) on Sept. 3, the authors analyze the reasons for the current global stall of nuclear energy capacity — which currently accounts for only 5 percent of global primary energy production — and discuss measures that could be taken to arrest and reverse that trend.

    The study group, led by MIT researchers in collaboration with colleagues from Idaho National Laboratory and the University of Wisconsin at Madison, is presenting its findings and recommendations at events in London, Paris, and Brussels this week, followed by events on Sept. 25 in Washington, and on Oct. 9 in Tokyo. MIT graduate and undergraduate students and postdocs, as well as faculty from Harvard University and members of various think tanks, also contributed to the study as members of the research team.

    “Our analysis demonstrates that realizing nuclear energy’s potential is essential to achieving a deeply decarbonized energy future in many regions of the world,” says study co-chair Jacopo Buongiorno, the TEPCO Professor and associate department head of the Department of Nuclear Science and Engineering at MIT. He adds, “Incorporating new policy and business models, as well as innovations in construction that may make deployment of cost-effective nuclear power plants more affordable, could enable nuclear energy to help meet the growing global demand for energy generation while decreasing emissions to address climate change.”

    The study team notes that the electricity sector in particular is a prime candidate for deep decarbonization. Global electricity consumption is on track to grow 45 percent by 2040, and the team’s analysis shows that the exclusion of nuclear from low-carbon scenarios could cause the average cost of electricity to escalate dramatically.

    “Understanding the opportunities and challenges facing the nuclear energy industry requires a comprehensive analysis of technical, commercial, and policy dimensions,” says Robert Armstrong, director of MITEI and the Chevron Professor of Chemical Engineering. “Over the past two years, this team has examined each issue, and the resulting report contains guidance policymakers and industry leaders may find valuable as they evaluate options for the future.”

    The report discusses recommendations for nuclear plant construction, current and future reactor technologies, business models and policies, and reactor safety regulation and licensing. The researchers find that changes in reactor construction are needed to usher in an era of safer, more cost-effective reactors, including proven construction management practices that can keep nuclear projects on time and on budget.

    “A shift towards serial manufacturing of standardized plants, including more aggressive use of fabrication in factories and shipyards, can be a viable cost-reduction strategy in countries where the productivity of the traditional construction sector is low,” says MIT visiting research scientist David Petti, study executive director and Laboratory Fellow at the Idaho National Laboratory. “Future projects should also incorporate reactor designs with inherent and passive safety features.”

    These safety features could include core materials with high chemical and physical stability and engineered safety systems that require limited or no emergency AC power and minimal external intervention. Features like these can reduce the probability of severe accidents occurring and mitigate offsite consequences in the event of an incident. Such designs can also ease the licensing of new plants and accelerate their global deployment.

    “The role of government will be critical if we are to take advantage of the economic opportunity and low-carbon potential that nuclear has to offer,” says John Parsons, study co-chair and senior lecturer at MIT’s Sloan School of Management. “If this future is to be realized, government officials must create new decarbonization policies that put all low-carbon energy technologies (i.e. renewables, nuclear, fossil fuels with carbon capture) on an equal footing, while also exploring options that spur private investment in nuclear advancement.”

    The study lays out detailed options for government support of nuclear. For example, the authors recommend that policymakers should avoid premature closures of existing plants, which undermine efforts to reduce emissions and increase the cost of achieving emission reduction targets. One way to avoid these closures is the implementation of zero-emissions credits — payments made to electricity producers where electricity is generated without greenhouse gas emissions — which the researchers note are currently in place in New York, Illinois, and New Jersey.

    Another suggestion from the study is that the government support development and demonstration of new nuclear technologies through the use of four “levers”: funding to share regulatory licensing costs; funding to share research and development costs; funding for the achievement of specific technical milestones; and funding for production credits to reward successful demonstration of new designs.

    The study includes an examination of the current nuclear regulatory climate, both in the United States and internationally. While the authors note that significant social, political, and cultural differences may exist among many of the countries in the nuclear energy community, they say that the fundamental basis for assessing the safety of nuclear reactor programs is fairly uniform, and should be reflected in a series of basic aligned regulatory principles. They recommend regulatory requirements for advanced reactors be coordinated and aligned internationally to enable international deployment of commercial reactor designs, and to standardize and ensure a high level of safety worldwide.

    The study concludes with an emphasis on the urgent need for both cost-cutting advancements and forward-thinking policymaking to make the future of nuclear energy a reality.

    "The Future of Nuclear Energy in a Carbon-Constrained World" is the eighth in the "Future of…" series of studies that are intended to serve as guides to researchers, policymakers, and industry. Each report explores the role of technologies that might contribute at scale in meeting rapidly growing global energy demand in a carbon-constrained world. Nuclear power was the subject of the first of these interdisciplinary studies, with the 2003 "Future of Nuclear Power" report (an update was published in 2009). The series has also included a study on the future of the nuclear fuel cycle. Other reports in the series have focused on carbon dioxide sequestration, natural gas, the electric grid, and solar power. These comprehensive reports are written by multidisciplinary teams of researchers. The research is informed by a distinguished external advisory committee.

June 5, 2018

  • Today, the Abdul Latif Jameel World Water and Food Security Lab (J-WAFS) at MIT announced the award of over $1.3 million in research funding through its seed grant program, now in its fourth year. These grants, which are available to the MIT community, are the cornerstone of MIT’s Institute-wide effort to catalyze solutions-oriented research in water and food systems that target the safety and resilience of the world’s vital resources. 

    This year, seven new projects led by eleven faculty PIs across six MIT departments will be funded with two-year grants of up to $200,000, overhead free. The winning projects include a silk-based food safety sensor; research into climate vulnerability and resilience in agriculture using biological engineering as well as crop modeling and sensors; an archeological and materials engineering approach to understanding fertile tropical soils; and three different strategies for water purification and management.

    The reach of the J-WAFS’s seed grants across the Institute is wide and reflects how faculty from all schools at MIT are invested in addressing the critical challenges that face our most essential global resources. This J-WAFS call for seed research proposals attracted 54 principal investigators, nearly twice the number that submitted proposals in 2017. What is more, 38 of these PIs were proposing to J-WAFS for the first time. “The J-WAFS seed grants continue to stimulate new thinking about how to address some of our most serious water and food problems, whether by new junior faculty at MIT or senior professors,” noted Renee Robins, executive director of J-WAFS.   

    Faculty from six departments were funded under this year's awards, including the departments of Civil and Environmental Engineering, Chemical Engineering, Earth, Atmospheric and Planetary Sciences, Materials Science and Engineering, Electrical Engineering and Computer Science, and Mechanical Engineering. 

    New approaches to ensure safe drinking water

    The problem of arsenic contamination in water occurs throughout the globe, and is particularly extreme in South Asia, where over 100 million people in Bangladesh, Nepal, India, Cambodia, Pakistan, Vietnam, and Myanmar experience daily exposure to dangerous concentrations of arsenic that occurs naturally in groundwater. Yet the poorly understood behavior of arsenic in groundwater makes it challenging to identify safe sources of drinking water. Charlie Harvey, professor of civil and environmental engineering, has conducted extensive field research on  this issue. With J-WAFS funding, Harvey will consolidate data and develop models to identify and disseminate more effective groundwater management strategies that take into account how and where dangerous concentrations of arsenic exist.      

    Julia Ortony, the Finmeccanica Career Development Assistant Professor of Engineering in the Department of Materials Science and Engineering, will be taking a different approach to arsenic contamination. Her lab develops molecular nanomaterials for environmental contaminant remediation. A J-WAFS seed grant will support her development of a robust, high surface-area material made of small molecules that can be designed to sequester arsenic from drinking water. 

    Boron is an essential micronutrient for both plants and animals, but becomes toxic at higher concentrations. However, due to its small molecular size and un-charged chemical structure, it is particularly difficult to remove with standard water purification technologies. Zachary P. Smith, the Joseph R. Mares Career Development Professor in the Department of Chemical Engineering, is taking advantage of advancements in molecular level synthesis of metal-organic framework (MOF) materials to open the door to a new generation of highly selective membranes for water purification and desalination that can remove boron. Leveraging techniques and expertise at the interface of inorganic chemistry, materials science, and chemical engineering, Smith aims to achieve technical breakthroughs in water purification with this J-WAFS funding.

    Improving understanding of soil and climate impacts on agriculture for improved crop production

    Climate change is bringing temperature and precipitation changes that will increasingly stress the crops our global food system depends on, and these changes will affect regions of the world differently. Breeding plants for increased resilience to stressors such as drought is one solution, but traditional breeding approaches can be extremely slow. In part, this slowness results from the complexity of plants’ response to environmental stress. David Des Marais, assistant professor in civil and environmental engineering, and Caroline Uhler, assistant professor of electrical engineering and computer science want to better understand this complexity in order to improve future practices to breed plants for stress tolerance. By combining Des Marais’ expertise in plant-environment interaction and sustainable agriculture with Uhler’s statistical approaches to studying networks, the team will develop new analytical tools to understand the structure and dynamics of the gene regulatory networks that plants use to perceive — and respond to — changes in the environment. 

    Dara Entekhabi, the Bacardi and Stockholm Water Foundations Professor in the departments of Civil and Environmental Engineering and Earth, Atmospheric and Planetary Sciences, is taking another approach to understanding the impacts of climate on agricultural production. The project, in collaboration with research scientist Sarah Fletcher from MIT’s Institute for Data, Systems, and Society, is focused on Sub-Saharan Africa. This region is experiencing very high population growth, and with its largely rain-fed agriculture is particularly vulnerable to anticipated temperature and precipitation changes brought about by climate change. The MIT research team is leading an academic-industry partnership that seeks to understand how crop production in the region responds to year-to-year variation in precipitation in order to assess the future of food security in Africa. They will collaborate with Radiant Earth, a startup that uses a geospatial imagery technology platform to capture and understand the impact of social challenges in the developing world, to develop a better understanding of the impact of climate on food security in Sub-Saharan Africa. 

    A very different approach to improving agricultural productivity involves better understanding and managing soil fertility. In another innovative multidisciplinary project, three PIs whose expertise spans geoscience, archaeology, and materials engineering will collaborate to improve our understanding of extensive deposits of rich soils known as terra preta (“dark earth” in Portuguese) in the Amazon Basin that pre-Columbian societies created and cultivated between 500 and about 8,700 years ago. Many tropical soils are nutrient-poor and contain little organic carbon, but terra preta is so carbon-rich and fertile that it is still farmed (and destructively mined) today. Researchers are now attempting to reproduce terra preta as part of a strategy for sustainable tropical agriculture and carbon sequestration. A team consisting of Taylor Perron, associate professor in the Department of Earth, Atmospheric and Planetary Sciences, and Dorothy Hosler and Heather Lechtman, both professors of archaeology and ancient technology in the Department of Materials Science and Engineering, aims to inform agricultural practices in tropical developing nations by investigating how the rivers of the Amazon region influenced terra preta formation.  

    Using edible food safety sensors to reduce food waste and disease

    While strategies to improve agricultural productivity are critical to global food security, minimizing food loss from farm to table is also considered to be necessary if we are to meet our future food needs. Cost-effective and easy-to-use methods of detecting food spoilage along the food supply chain can help. A. John Hart, associate professor of mechanical engineering, and Benedetto Marelli, the Paul M. Cook Career Development Professor in the Department of Civil and Environmental Engineering, have teamed up to find a solution. J-WAFS seed funding is supporting the development of a silk-based food safety sensor, visible to the naked eye, which can change color based on its interaction with common food pathogens. The sensor will take the form of printable inks that are stable under extreme temperatures and also edible. Their aim is to print on food packaging as well as directly on food in order to enable point-of-use detection of contamination and food spoilage for meat and dairy products.

    With these seven newly funded projects, J-WAFS will have funded 30 total seed research projects since its founding in 2014. J-WAFS’ director John Lienhard states that “investing in research results in creative innovations in food and water that will enable a sustainable future.  Further, these seed grants have repeatedly been leveraged by their recipients to develop significant follow-on programs, that further multiply the impact.” 

    2018 J-WAFS Seed Grant recipients and their projects:

    "Novel systems biology tools for improving crop tolerance to abiotic stressors." PIs: David Des Marais, assistant professor in the Department of Civil and Environmental Engineering, and Caroline Uhler, the Henry L. and Grace Doherty Assistant Professor in the Department of Electrical Engineering and Computer Science and Institute for Data, Systems and Society.

    "Assessing Climate Vulnerability of West African Food Security using Remote Sensing." PIs: Dara Entekhabi, the Bacardi and Stockholm Water Foundations Professor in the Department of Civil and Environmental Engineering.

    "Printed Silk-Based Colorimetric Sensors for Food Spoilage Prevention and Supply Chain Authentication." PIs: A. John Hart, associate professor in the Department of Mechanical Engineering, and Benedetto Marelli, the Paul M. Cook Career Development Professor in the Department of Civil and Environmental Engineering.

    "What controls Arsenic Contamination in South Asia? Making Sense of Two-Decades of Disjointed Data." PI: Charles Harvey, professor in the Department of Civil and Environmental Engineering.

    "Supermolecular nanostructure gels for chelation of arsenic from drinking water." PI: Julia Ortony, the Finmeccanica Career Development Professor in the Department of Materials Science and Engineering.

    "Anthropogenic Soils of the Amazon: Origins, Extent, and Implications for Sustainable Tropical Agriculture." PIs: Dorothy Hosler, Professor of Archaeology and Ancient Technology, Department of Materials Science and Engineering, Heather Lechtman, Professor of Archaeology and Ancient Technology, Department of Materials Science and Engineering, and J. Taylor Perron, Associate Professor of Geology, Department of Earth, Planetary and Atmospheric Sciences.

    "Purifying Water from Boron Contamination with Highly Selective Metal-Organic Framework (MOF) Membranes." PI: Zachary Smith, the Joseph R. Mares Career Development Professor in the Department of Chemical Engineering.

May 31, 2018

  • Tiziana Smith has had her mind on water for years. The San Antonio native learned about the importance of preserving the city’s water resources in grade school — and has used that knowledge as a springboard into her research at MIT.

    “I was always aware of the importance of water and the potential tension between urban uses and agriculture,” says Smith, a fifth-year graduate student in the Department of Civil and Environmental Engineering. “This idea of understanding how to allocate a limited resource and how to use it efficiently is really interesting to me — especially in the agricultural sector, which is the world’s the largest user of water.”  

    As an undergraduate at Harvard University, Smith studied environmental science and public policy, and researched wastewater reuse in urban areas. After graduating, she worked as a research assistant at the World Bank in Hanoi, Vietnam, where she was able to study firsthand how agriculture can affect ways of life. For Smith, resource availability and global agricultural research “have a lot to do with livelihoods and providing people with a safe environment to live in and trying to make our food system more equitable.”

    While in Vietnam, Smith realized she wanted to gain a stronger technical background to prepare her to study the resource availability problems of the future. After working with the World Bank for two years, Smith returned to Cambridge, Massachusetts, as a graduate student in the MIT Technology and Policy Program.

    Smith worked with Dennis McLaughlin, the H.M. King Bhumibol Professor of Water Resource Management, to study the implications of land and water restrictions on food production in China. After graduating with a dual master’s degree in environmental engineering and technology and policy, she decided to stay on for a PhD.

    Building a model

    Smith’s doctoral research builds off her master’s research and aims to answer the question: How many people can China feed? “This question is interesting because China has the world’s largest population right now, and people are getting richer and richer,” Smith says. “So [the Chinese population] is demanding better diets with more meat and vegetables, which requires more resources.”

    Smith says changes in those diets have coincided with changes in how China gets its food — moving from a self-sufficient agricultural economy to one in which more food is being imported — but the exact mechanisms for this change are unclear.

    “What are the reasons they’re [importing more]?” Smith asks. “Is it because they really don’t have enough resources to grow the food themselves, or is it for economic or political reasons? We’re trying to understand if their food production system is limited by their resources or not.”

    “Preliminary results indicate that food production could be increased in China by changing current cropping patterns and investing in irrigation infrastructure,” she adds.

    Smith has developed a hydrological model that simulates the relationship between water availability and crop yields in China. “Understanding how much water the crops are taking up and evaporating is pretty crucial to understanding if [China is] water-limited or not,” she says. Smith is not the first to work on this modeling project, but she’s made key contributions, including upping the temporal resolution of the model and taking advantage of new global and regional data, including information from satellites.

    To calibrate the computer model and perform simulations, Smith uses satellite data, climate data, and data from rain and stream gauges. Access to regular, reliable data is key to the model’s success. In April 2017, Smith traveled with 23 other MIT students to Washington, as part of the MIT Science Policy Initiative. There, she advocated for funding for NASA’s Earth-monitoring satellites, some of which provide the crucial data for her models.

    While the models Smith develops in her research may help answer questions about the true agricultural capacity of China, she believes her research impact extends globally.

    “[How much food can be grown] is an interesting question to ask in many other parts of the world, for example sub-Saharan Africa, where the population is expected to increase rapidly and the demand for food is expected to increase more quickly than in China,” Smith says. “Knowing if and where it would be best to grow crops is an interesting question. We’re hoping that the methodology that we are developing can be used anywhere.”

    Supporting others

    When Smith isn’t at her computer refining or running her models, she can be found organizing activities and initiatives to help her fellow graduate students find mentors and become leaders themselves.

    In 2016, Smith participated in the MIT Graduate Student Leadership Institute, which gathers a class of graduate students to participate in weekly discussions on personal reflections and leadership. In 2017, Smith participated in the initiative again — but this time as a leadership team member.

    “It’s been a great opportunity to meet people from across the campus and also have a space for reflection about what I want to do with my life,” Smith says. “It’s been really rewarding.”

    In addition, Smith is a member of the Academy of Courageous Minority Engineers, a graduate student group that meets up weekly to discuss graduate life and the challenges faced by minority students. This year, Smith co-led a new initiative to invite faculty of color for lunch events with graduate students.

    Smith has similarly organized a lunch series for women graduate students and faculty in civil and environmental engineering. One of her motivations for putting together these events is that none of her PhD classes at MIT have been taught by women professors. “I feel like there’s not a lot of chances to get mentorship, and I hope that this is a way that [women faculty] can become more and more accessible,” Smith says.

    After Smith defends her dissertation, she hopes to find work in a field that uses both her technological and policy skillsets.

    “I did the Technology and Policy Program because I like bridging between major stakeholders and scientists. Hopefully, I won’t be the person who’s doing the coding forever,” Smith says cheerily. “I want to find a position where I can do analyses and interact with stakeholders — and it’s tricky to find the place where you can do both.”

May 23, 2018

  • Abigail Krich is the founder and president of Boreas Renewables, a consulting firm serving renewable energy developers, owners, operators, and advocates. She recently gave a talk at MIT, hosted by the MIT Energy Initiative (MITEI), to discuss New England’s looming transition from a natural-gas-dominated market to the renewables integration that will be necessary to meet policy deadlines for decarbonization. She argued for a rethinking of New England’s fundamental market design, pointing to the larger ongoing conversation of how to reconcile markets and public policy on regional, national, and global levels. MITEI Communications followed up with her to learn more.

    Q: The essence of your talk was that “something’s not matching up” between New England’s policy requirements for decarbonization and its wholesale electricity market design. Moving forward, are you optimistic about electricity markets adapting, or do you think state contracts and regulated rates will need to take on a larger role in implementing clean energy?

    A: I’m currently optimistic that the electricity markets will adapt incrementally to the short-term future, in which state contracts and regulated rates continue to take on a larger role but do not overtake the marketplace. Though I want to be, I’m not currently feeling optimistic that this process will be able to develop a long-term competitive market solution that will work for a nearly decarbonized electricity system. I do think it’s possible that an entirely different market structure could work, but this would likely be ordered by a regulator, either at the state or federal level, and seems unlikely to come from within the existing market improvement process. The biggest problem in my mind is: When the transition happens from the short term incremental changes that keep the system working to the long term, something fundamentally different is needed.

    Q: You noted that an increasing percentage of the energy supply (rooftop solar panels, for example) is operating outside the capacity market, reducing demand within the market itself. How will these external suppliers impact the clean energy transition?

    A: About two-thirds of the solar installed in New England is what’s called “behind the meter,” reducing the demand for electricity that is seen by the wholesale electricity markets. By reducing the demand for electricity from the wholesale markets, this solar also reduces the amount of capacity that must be purchased in the capacity market and helps the region’s clean energy transition. The other third of the solar installed here is what’s called “in front of the meter,” meaning it is treated like a typical generator in the wholesale electricity markets instead of reducing demand. Though the energy produced by this solar displaces the need for energy from fossil fired generators, hardly any of this solar is participating in the capacity market. By not participating in that piece of the wholesale markets, the capacity market completely ignores this solar, as though it weren’t even there. That’s a real shame because, even though it’s reducing the amount of energy each fossil plant produces, it isn’t helping the region to allow those fossil generators to retire (or to signal that we don’t need new fossil generators to be built). It would be great if either the market or policies changed to encourage this solar to participate in the capacity market or reduce demand so that it could be counted one way or another.

    Q: In order to meet emission reductions requirements, you argue that we must reduce electricity demand along with transitioning to low- and zero-carbon sources. New England’s energy efficiency measures have already brought down net demand drastically. How important is reducing demand in comparison to implementing renewables?

    A: I’m a huge proponent of clean energy, so I’m happy to see wind turbines popping up and solar panels installed wherever there is space. But I’m also an outdoor enthusiast who loves natural vistas unblemished by development. I think addressing the threat of climate change is far more important than preserving my views, but it would still be nice to keep some of them. Even if all of our electricity came from carbon-free sources, I still think reducing demand through energy efficiency and price-responsive demand is important so that we can limit the impact of these clean energy sources on the environment around us.

    This event was supported by IHS Markit.

  • Every year, Sustainability Connect, a forum organized by the MIT Office of Sustainability (MITOS), provides an opportunity for MIT community members working on sustainability issues across campus to come together around a cross-cutting theme, celebrate accomplishments, and engage in collective brainstorming. The event furthers MITOS’ mission to transform MIT into a powerful model that generates new ways of responding to the challenges of a changing planet, starting by using our own campus as a testbed.

    On May 7, a group of 80 faculty, staff, and students convened for Sustainability Connect 2018 to discuss this year’s theme: “Imagine. Incubate. Impact.” The fourth annual event opened with a keynote from Joi Ito, director of the MIT Media Lab. Ito’s work at the Media Lab — taking big problems in the real world, scaling them down, and then testing, proving, and deploying solutions – deeply aligns with the approach MIT is taking on campus sustainability and provided an inspirational framework for the day’s sessions. Ito stressed the necessity of shifting paradigms when trying to change complex environmental systems.

    He also shared a note of optimism about young leaders entering the workforce.

    “People’s values are changing,” he said. “When you look at millennials going into companies, they care about the social cause. I think it’s important to harness that.”

    The student leaders who participated in Sustainability Connect throughout the day — engaging with the audience to tackle issues such as carbon neutrality and water management on our campus — helped drive this message home.

    Deputy Executive Vice President Tony Sharon provided examples of how MIT is already changing the game on sustainability at MIT in his opening remarks, noting progress on the MIT solar farm in North Carolina, the utility of the MIT DataHub, and the recently released Pathways for Sustainability Leadership report.

    During the morning session, MITOS took the opportunity to officially launch the Sustainability DataPool, MIT's portal to campus sustainability data. MITOS worked closely with Information Systems and Technology to develop this website, which now enables and invites the community to explore campus datasets and visualizations powered by the MIT DataHub.

    “As research suggests, we think there’s a connection between an organization like MIT’s ability to innovate and the accessibility of shared data,” said Derek Wietsma, senior data analyst at MITOS. “As this resource matures, we hope the Sustainability DataPool will play an important role in MIT's ability to develop and implement sustainable solutions.”

    The morning sessions spotlighted many staff, students, and faculty at MIT working toward imagining, incubating, and making an impact on a range of campus sustainability topics.

    The panel, “The State of Sustainability at MIT,” featured Amanda Graham, executive director of the Environmental Solutions Intiative; Kate Trimble, associate dean of PKG Public Service Center; Christina Lo, the director of Strategic Sourcing and Contracts; and Abigail Francis, assistant dean of LBGTQ+ Services. They discussed sustainability efforts through a multitude of lenses and explored topics ranging from integrating sustainability into the MIT curriculum to activating public service around climate change to advancing equity on campus. Christina Lo spoke about changing the purchasing paradigm at MIT from: “Let’s get what we need” to “Is there another way to think about what our true goals are?”

    During a speed talk session, the recipients of the first Sustainability Incubator Awards updated the audience on their research, detailing how they have been using the campus as a test bed. The audience learned about disposable glove recycling, lifecycle analysis of buildings, and capturing and reusing water vapor plumes from the MIT Central Utilities Plant, which could result in significant water savings for the Institute and beyond.

    The final panel featured students from a new spring course 11.S938 / 2.S999 (Solving for Carbon Neutrality) designed and taught by Tim Gutowski, a professor of mechanical engineering and Director of Sustainability Julie Newman. The students unveiled their emerging ideas on how MIT might transition to a carbon neutral future free from fossil fuels. The panel featured mechanical engineering graduate students Julien Barber, Caleb Amy, and Colin Kelsall, and economics student Ignacio Ortega Castineiras. They shared a mix of technology and financial models they are currently grappling with as the semester comes to a close.

    After engaging in many conversations framed by science and engineering, Heather Paxson, a professor of anthropology gave a lunchtime keynote addressing the connection between culture and food. As MIT explores its own food system — from procurement to growing food on campus — Paxson’s comments reminded attendees that culture also plays an important role in solving for environmental problems.

    “Beyond its symbolic capacity, food is also a medium of communication and of social power,” she said. “Food isn’t just culturally relevant — food is culture.”

    To conclude the event, the group split up into three workshop tracks to provide input into campus-wide discussions of water management, food and sustainability, and the implementation of the Pathway to Sustainability Leadership report.

    “The momentum to shift paradigms, solve complex problems, and cross traditional lines in order to collaborate is building at MIT and can be seen across MIT’s operations already,” said Julie Newman. “This June, we hope to leverage this work and plan for the next decade, finding new ways for MIT to be a game changer in the space of campus sustainability as we seek to implement the new vision outlined the Pathway to Sustainability report.”

    For MIT community members who want to get involved in the campus sustainability design process, MITOS encourages participation in the June 1 Pathway to Sustainability implementation forum. Anyone interested is encouraged to RSVP by May 25.