Environment

Subterms

    More stories

    • 100 Shares179 Views

      in Environment

      Selective separation could help alleviate critical metals shortage

      by

      New processing methods developed by MIT researchers could help ease looming shortages of the essential metals that power everything from phones to automotive batteries, by making it easier to separate these rare metals from mining ores and recycled materials.

      Selective adjustments within a chemical process called sulfidation allowed professor of metallurgy Antoine Allanore and his graduate student Caspar Stinn to successfully target and separate rare metals, such as the cobalt in a lithium-ion battery, from mixed-metal materials.

      As they report in the journal Nature, their processing techniques allow the metals to remain in solid form and be separated without dissolving the material. This avoids traditional but costly liquid separation methods that require significant energy. The researchers developed processing conditions for 56 elements and tested these conditions on 15 elements.

      Their sulfidation approach, they write in the paper, could reduce the capital costs of metal separation between 65 and 95 percent from mixed-metal oxides. Their selective processing could also reduce greenhouse gas emissions by 60 to 90 percent compared to traditional liquid-based separation.

      “We were excited to find replacements for processes that had really high levels of water usage and greenhouse gas emissions, such as lithium-ion battery recycling, rare-earth magnet recycling, and rare-earth separation,” says Stinn. “Those are processes that make materials for sustainability applications, but the processes themselves are very unsustainable.”

      The findings offer one way to alleviate a growing demand for minor metals like cobalt, lithium, and rare earth elements that are used in “clean” energy products like electric cars, solar cells, and electricity-generating windmills. According to a 2021 report by the International Energy Agency, the average amount of minerals needed for a new unit of power generation capacity has risen by 50 percent since 2010, as renewable energy technologies using these metals expand their reach.

      Opportunity for selectivity

      For more than a decade, the Allanore group has been studying the use of sulfide materials in developing new electrochemical routes for metal production. Sulfides are common materials, but the MIT scientists are experimenting with them under extreme conditions like very high temperatures — from 800 to 3,000 degrees Fahrenheit — that are used in manufacturing plants but not in a typical university lab.

      “We are looking at very well-established materials in conditions that are uncommon compared to what has been done before,” Allanore explains, “and that is why we are finding new applications or new realities.”

      In the process of synthetizing high-temperature sulfide materials to support electrochemical production, Stinn says, “we learned we could be very selective and very controlled about what products we made. And it was with that understanding that we realized, ‘OK, maybe there’s an opportunity for selectivity in separation here.’”

      The chemical reaction exploited by the researchers reacts a material containing a mix of metal oxides to form new metal-sulfur compounds or sulfides. By altering factors like temperature, gas pressure, and the addition of carbon in the reaction process, Stinn and Allanore found that they could selectively create a variety of sulfide solids that can be physically separated by a variety of methods, including crushing the material and sorting different-sized sulfides or using magnets to separate different sulfides from one another.

      Current methods of rare metal separation rely on large quantities of energy, water, acids, and organic solvents which have costly environmental impacts, says Stinn. “We are trying to use materials that are abundant, economical, and readily available for sustainable materials separation, and we have expanded that domain to now include sulfur and sulfides.”

      Stinn and Allanore used selective sulfidation to separate out economically important metals like cobalt in recycled lithium-ion batteries. They also used their techniques to separate dysprosium — a rare-earth element used in applications ranging from data storage devices to optoelectronics — from rare-earth-boron magnets, or from the typical mixture of oxides available from mining minerals such as bastnaesite.

      Leveraging existing technology

      Metals like cobalt and rare earths are only found in small amounts in mined materials, so industries must process large volumes of material to retrieve or recycle enough of these metals to be economically viable, Allanore explains. “It’s quite clear that these processes are not efficient. Most of the emissions come from the lack of selectivity and the low concentration at which they operate.”

      By eliminating the need for liquid separation and the extra steps and materials it requires to dissolve and then reprecipitate individual elements, the MIT researchers’ process significantly reduces the costs incurred and emissions produced during separation.

      “One of the nice things about separating materials using sulfidation is that a lot of existing technology and process infrastructure can be leveraged,” Stinn says. “It’s new conditions and new chemistries in established reactor styles and equipment.”

      The next step is to show that the process can work for large amounts of raw material — separating out 16 elements from rare-earth mining streams, for example. “Now we have shown that we can handle three or four or five of them together, but we have not yet processed an actual stream from an existing mine at a scale to match what’s required for deployment,” Allanore says.

      Stinn and colleagues in the lab have built a reactor that can process about 10 kilograms of raw material per day, and the researchers are starting conversations with several corporations about the possibilities.

      “We are discussing what it would take to demonstrate the performance of this approach with existing mineral and recycling streams,” Allanore says.

      This research was supported by the U.S. Department of Energy and the U.S. National Science Foundation. More

    • 88 Shares179 Views

      in Energy

      “Vigilant inclusion” central to combating climate change

      by

      “To turbocharge work on saving the planet, we need effective, innovative, localized solutions, and diverse perspectives and experience at the table,” said U.S. Secretary of Energy Jennifer M. Granholm, the keynote speaker at the 10th annual U.S. Clean Energy Education and Empowerment (C3E) Women in Clean Energy Symposium and Awards.

      This event, convened virtually over Nov. 3-4 and engaging more than 1,000 participants, was devoted to the themes of justice and equity in clean energy. In panels and presentations, speakers hammered home the idea that the benefits of a zero-carbon future must be shared equitably, especially among groups historically neglected or marginalized. To ensure this outcome, the speakers concluded, these same groups must help drive the clean-energy transition, and women, who stand to bear enormous burdens as the world warms, should be central to the effort. This means “practicing vigilant inclusion,” said Granholm.

      The C3E symposium, which is dedicated to celebrating the leadership of women in the field of clean energy and inspiring the next generation of women leaders, featured professionals from government, industry, research, and other sectors. Some of them spoke from experience, and from the heart, on issues of environmental justice.

      “I grew up in a trailer park in northern Utah, where it was so cold at night a sheet of ice formed on the inside of the door,” said Melanie Santiago-Mosier, the deputy director of the Clean Energy Group and Clean Energy States Alliance. Santiago-Mosier, who won a 2018 C3E award for advocacy, has devoted her career “to bringing the benefits of clean energy to families like mine, and to preventing mistakes of the past that result in a deeply unjust energy system.”

      Tracey A. LeBeau, a member of the Cheyenne River Sioux Tribe who grew up in South Dakota, described the flooding of her community’s land to create a hydroelectric dam, forcing the dislocation of many people. Today, as administrator and CEO of the Western Area Power Administration, LeBeau manages distribution of hydropower across 15 states, and has built an organization in which the needs of disadvantaged communities are top of mind. “I stay true to my indigenous point of view,” she said.

      The C3E Symposium was launched in 2012 to increase gender diversity in the energy sector and provide awards to outstanding women in the field. It is part of the C3E Initiative, a collaboration between the U.S. Department of Energy (DOE), the MIT Energy Initiative (MITEI), Texas A&M Energy Institute, and Stanford Precourt Institute for Energy, which hosted the event this year.

      Connecting global rich and poor

      As the COP26 climate summit unfolded in Glasgow, highlighting the sharp divide between rich and poor nations, C3E panelists pursued a related agenda. One panel focused on paths for collaboration between industrialized nations and nations with developing economies to build a sustainable, carbon-neutral global economy.

      Radhika Thakkar, the vice president of corporate affairs at solar home energy provider Greenlight Planet and a 2019 C3E international award winner, believes that small partnerships with women at the community level can lead to large impacts. When her company introduced solar lamp home systems to Rwanda, “Women abandoned selling bananas to sell our lamps, making enough money to purchase land, cows, even putting their families through school,” she said.

      Sudeshna Banerjee, the practice manager for Europe and Central Asia and the energy and extractives global practice at the World Bank, talked about impacts of a bank-supported electrification program in Nairobi slums where gang warfare kept girls confined at home. “Once the lights came on, girls felt more empowered to go around in dark hours,” she said. “This is what development is: creating opportunities for young women to do something with their lives, giving them educational opportunities and creating instances for them to generate income.”

      In another session, panelists focused on ways to enable disadvantaged communities in the United States to take full advantage of clean energy opportunities.

      Amy Glasmeier, a professor of economic geography and regional planning at MIT, believes remote, rural communities require broadband and other information channels in order to chart their own clean-energy journeys. “We must provide access to more than energy, so people can educate themselves and imagine how the energy transition can work for them.”

      Santiago-Mosier described the absence of rooftop solar in underprivileged neighborhoods of the nation’s cities and towns as the result of a kind of clean-energy redlining. “Clean energy and the solar industry are falling into 400-year-old traps of systemic racism,” she said. “This is no accident: senior executives in solar are white and male.” The answer is “making sure that providers and companies are elevating people of color and women in industries,” otherwise “solar is leaving potential growth on the table.”

      Data for equitable outcomes

      Jessica Granderson, the director of building technology at the White House Council on Environmental Quality and the 2015 C3E research award winner, is measuring and remediating greenhouse gas emissions from the nation’s hundred-million-plus homes and commercial structures. In a panel exploring data-driven solutions for advancing equitable energy outcomes, Granderson described using new building performance standards that improve the energy efficiency and material performance of construction in a way that does not burden building owners with modest resources. “We are emphasizing engagements at the community level, bringing in a local workforce, and addressing the needs of local programs, in a way that hasn’t necessarily been present in the past,” she said.

      To facilitate her studies on how people in these communities use and experience public transportation systems, Tierra Bills, an assistant professor in civil and environmental engineering at Wayne State University, is developing a community-based approach for collecting data. “Not everyone who is eager to contribute to a study can participate in an online survey and upload data, so we need to find ways of overcoming these barriers,” she said.

      Corporate efforts to advance social and environmental justice turn on community engagement as well. Paula Gold-Williams, a C3E ambassador and the president and CEO of CPS Energy, with 1 million customers in San Antonio, Texas, described a weatherization campaign to better insulate homes that involved “looking for as many places to go as possible in parts of town where people wouldn’t normally raise their hands.”

      Carla Peterman, the executive vice president for corporate affairs and chief of sustainability at Pacific Gas & Electric, and the 2015 C3E government award winner, was deliberating about raising rates some years ago. “My ‘aha’ moment was in a community workshop where I realized that a $5 increase is too much,” she said. “It may be the cost of a latte, but these folks aren’t buying lattes, and it’s a choice between electricity and food or shelter.”

      A call to arms

      Humanity cannot win the all-out race to achieve a zero-carbon future without a vast new cohort of participants, symposium speakers agreed. A number of the 2021 C3E award winners who have committed their careers to clean energy invoked the moral imperative of the moment and issued a call to arms.

      “Seven-hundred-and-fifty million people around the world live without reliable energy, and 70 percent of schools lack power,” said Rhonda Jordan-Antoine PhD ’12, a senior energy specialist at the World Bank who received this year’s international award. By laboring to bring smart grids, battery technologies, and regional integration to even the most remote communities, she said, we open up opportunities for education and jobs. “Energy access is not just about energy, but development,” said Antoine, “and I hope you are encouraged to advance clean energy efforts around the globe.”

      Faith Corneille, who won the government award, works in the U.S. Department of State’s Bureau of Energy Resources. “We need innovators and scientists to design solutions; energy efficiency experts and engineers to build; lawyers to review, and bankers to invest, and insurance agents to protect against risk; and we need problem-solvers to thread these together,” she said. “Whatever your path, there’s a role for you: energy and climate intersect with whatever you do.”

      “We know the cause of climate change and how to reverse it, but to make that happen we need passionate and brilliant minds, all pulling in the same direction,” said Megan Nutting, the executive vice president of government and regulatory affairs at Sunnova Energy Corporation, and winner of the business award. “The clean-energy transition needs women,” she said. “If you are not working in clean energy, then why not?” More

    • 138 Shares179 Views

      in Environment

      3 Questions: Tolga Durak on building a safety culture at MIT

      by

      Environment, Health, and Safety Managing Director Tolga Durak heads a team working to build a strong safety culture at the Institute and to implement systems that lead to successful lab and makerspace operations. EHS is also pursuing new opportunities in the areas of safe and sustainable labs and applied makerspace research. 

      Durak holds a BS in mechanical engineering, a MS in industrial and systems engineering, and a PhD in building construction/environmental design and planning. He has over 20 years of experience in engineering and EHS in higher education, having served in such roles as authority having jurisdiction, responsible official, fire marshal, risk manager, radiation safety officer, laser safety officer, safety engineer, project manager, and emergency manager for government agencies, as well as universities with extensive health-care and research facilities.

      Q: What “words of wisdom” regarding lab/shop health and safety would you like to share with the research community? 

      A: EHS staff always strive to help maintain the safety and well-being of the MIT community. When it comes to lab/shop safety or any areas with hazards, first and foremost, we encourage wearing the appropriate personal protective equipment (PPE) when handling potentially hazardous materials. While PPE needs depend on the hazards and the space, common PPE includes safety glasses, lab coats, gloves, clothes that cover your skin, and closed-toe shoes. Shorts and open-toe shoes have no place in the lab/shop setting when hazardous materials are stored or used. Accidents will and do happen. The severity of injuries due to accidental exposures can be minimized when researchers are wearing PPE. Remember, there is only one you!   

      Overall, be aware of your surroundings, be knowledgeable about the hazards of the materials and equipment you are using, and be prepared for the unexpected. Ask yourself, “What’s the worst thing that can happen during this experiment or procedure?” Prepare by doing a thorough risk assessment, ask others who may be knowledgeable for their ideas and help, and standardize procedures where possible. Be prepared to respond appropriately when an emergency arises. 

      Safety in our classrooms, labs, and makerspaces is paramount and requires a collaborative effort. 

      Q: What are the established programs within EHS that students and researchers should be aware of, and what opportunities and challenges do you face trying to advance a healthy safety culture at MIT? 

      A: The EHS program staff in Biosafety, Industrial Hygiene, Environmental Management, Occupational and Construction Safety, and Radiation Protection are ready to assist with risk assessments, chemical safety, physical hazards, hazard-specific training, materials management, and hazardous waste disposal and reuse/recycling. Locally, each department, laboratory, and center has an EHS coordinator, as well as an assigned EHS team, to assist in the implementation of required EHS programs. Each lab/shop also has a designated EHS representative — someone who has local knowledge of your lab/shop and can help you with safety requirements specific to your work area.  

      One of the biggest challenges we face is that due to the decentralized nature of the Institute, no one size fits all when it comes to implementing successful safety practices. We also view this as an opportunity to enhance our safety culture. A strong safety culture is reflected at MIT when all lab and makerspace members are willing to look out for each other, challenge the status quo when necessary, and do the right thing even when no one is looking. In labs/shops with a strong safety culture, faculty and researchers discuss safety topics at group meetings, group members remind each other to wear the appropriate PPE (lab coats, safety glasses, etc.), more experienced team members mentor the newcomers, and riskier operations are reviewed and assessed to make them as safe as possible.  

      Q: Can you describe the new Safe and Sustainable Laboratories (S2L) efforts and the makerspace operational research programs envisioned for the future? 

      A: The MIT EHS Office has a plan for renewing its dedication to sustainability and climate action. We are dedicated to doing our part to promote a research environment that assures the highest level of health and safety but also strives to reduce energy, water, and waste through educating and supporting faculty, students, and researchers. With the goal of integrating sustainability across the lab sector of campus and bridging that with the Institute’s climate action goals, EHS has partnered with the MIT Office of Sustainability, Department of Facilities, vice president for finance, and vice president for campus services and stewardship to relaunch the “green” labs sustainability efforts under a new Safe and Sustainable Labs program.

      Part of that plan is to implement a Sustainable Labs Certification program. The process is designed to be as easy as possible for the lab groups. We are starting with simple actions like promoting the use of equipment timers in certain locations to conserve energy, fume hood/ventilation management, preventative maintenance for ultra-low-temperature freezers, increasing recycling, and helping labs update their central chemical inventory system, which can help forecast MIT’s potential waste streams. 

      EHS has also partnered with Project Manus to build a test-bed lab to study potential health and environmental exposures present in makerspaces as a result of specialized equipment and processes with our new Applied Makerspace Research Initiative.   More

    • 125 Shares109 Views

      in Environment

      Climate modeling confirms historical records showing rise in hurricane activity

      by

      When forecasting how storms may change in the future, it helps to know something about their past. Judging from historical records dating back to the 1850s, hurricanes in the North Atlantic have become more frequent over the last 150 years.

      However, scientists have questioned whether this upward trend is a reflection of reality, or simply an artifact of lopsided record-keeping. If 19th-century storm trackers had access to 21st-century technology, would they have recorded more storms? This inherent uncertainty has kept scientists from relying on storm records, and the patterns within them, for clues to how climate influences storms.

      A new MIT study published today in Nature Communications has used climate modeling, rather than storm records, to reconstruct the history of hurricanes and tropical cyclones around the world. The study finds that North Atlantic hurricanes have indeed increased in frequency over the last 150 years, similar to what historical records have shown.

      In particular, major hurricanes, and hurricanes in general, are more frequent today than in the past. And those that make landfall appear to have grown more powerful, carrying more destructive potential.

      Curiously, while the North Atlantic has seen an overall increase in storm activity, the same trend was not observed in the rest of the world. The study found that the frequency of tropical cyclones globally has not changed significantly in the last 150 years.

      “The evidence does point, as the original historical record did, to long-term increases in North Atlantic hurricane activity, but no significant changes in global hurricane activity,” says study author Kerry Emanuel, the Cecil and Ida Green Professor of Atmospheric Science in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. “It certainly will change the interpretation of climate’s effects on hurricanes — that it’s really the regionality of the climate, and that something happened to the North Atlantic that’s different from the rest of the globe. It may have been caused by global warming, which is not necessarily globally uniform.”

      Chance encounters

      The most comprehensive record of tropical cyclones is compiled in a database known as the International Best Track Archive for Climate Stewardship (IBTrACS). This historical record includes modern measurements from satellites and aircraft that date back to the 1940s. The database’s older records are based on reports from ships and islands that happened to be in a storm’s path. These earlier records date back to 1851, and overall the database shows an increase in North Atlantic storm activity over the last 150 years.

      “Nobody disagrees that that’s what the historical record shows,” Emanuel says. “On the other hand, most sensible people don’t really trust the historical record that far back in time.”

      Recently, scientists have used a statistical approach to identify storms that the historical record may have missed. To do so, they consulted all the digitally reconstructed shipping routes in the Atlantic over the last 150 years and mapped these routes over modern-day hurricane tracks. They then estimated the chance that a ship would encounter or entirely miss a hurricane’s presence. This analysis found a significant number of early storms were likely missed in the historical record. Accounting for these missed storms, they concluded that there was a chance that storm activity had not changed over the last 150 years.

      But Emanuel points out that hurricane paths in the 19th century may have looked different from today’s tracks. What’s more, the scientists may have missed key shipping routes in their analysis, as older routes have not yet been digitized.

      “All we know is, if there had been a change (in storm activity), it would not have been detectable, using digitized ship records,” Emanuel says “So I thought, there’s an opportunity to do better, by not using historical data at all.”

      Seeding storms

      Instead, he estimated past hurricane activity using dynamical downscaling — a technique that his group developed and has applied over the last 15 years to study climate’s effect on hurricanes. The technique starts with a coarse global climate simulation and embeds within this model a finer-resolution model that simulates features as small as hurricanes. The combined models are then fed with real-world measurements of atmospheric and ocean conditions. Emanuel then scatters the realistic simulation with hurricane “seeds” and runs the simulation forward in time to see which seeds bloom into full-blown storms.

      For the new study, Emanuel embedded a hurricane model into a climate “reanalysis” — a type of climate model that combines observations from the past with climate simulations to generate accurate reconstructions of past weather patterns and climate conditions. He used a particular subset of climate reanalyses that only accounts for observations collected from the surface — for instance from ships, which have recorded weather conditions and sea surface temperatures consistently since the 1850s, as opposed to from satellites, which only began systematic monitoring in the 1970s.

      “We chose to use this approach to avoid any artificial trends brought about by the introduction of progressively different observations,” Emanuel explains.

      He ran an embedded hurricane model on three different climate reanalyses, simulating tropical cyclones around the world over the past 150 years. Across all three models, he observed “unequivocal increases” in North Atlantic hurricane activity.

      “There’s been this quite large increase in activity in the Atlantic since the mid-19th century, which I didn’t expect to see,” Emanuel says.

      Within this overall rise in storm activity, he also observed a “hurricane drought” — a period during the 1970s and 80s when the number of yearly hurricanes momentarily dropped. This pause in storm activity can also be seen in historical records, and Emanuel’s group proposes a cause: sulfate aerosols, which were byproducts of fossil fuel combustion, likely set off a cascade of climate effects that cooled the North Atlantic and temporarily suppressed hurricane formation.

      “The general trend over the last 150 years was increasing storm activity, interrupted by this hurricane drought,” Emanuel notes. “And at this point, we’re more confident of why there was a hurricane drought than why there is an ongoing, long-term increase in activity that began in the 19th century. That is still a mystery, and it bears on the question of how global warming might affect future Atlantic hurricanes.”

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

    • 88 Shares109 Views

      in Environment

      Scientists and musicians tackle climate change together

      by

      Audiences may travel long distances to see their favorite musical acts in concert or to attend large music festivals, which can add to their personal carbon footprint of emissions that are steadily warming the planet. But these same audiences, and the performers they follow, are often quite aware of the dangers of climate change and eager to contribute to ways of curbing those emissions.

      How should the industry reconcile these two perspectives, and how should it harness the enormous influence that musicians have on their fans to help promote action on climate change?

      That was the focus of a wide-ranging discussion on Monday hosted by MIT’s Environmental Solutions Initiative, titled “Artists and scientists together on climate solutions.” The event, which was held live at the Media Lab’s Bartos Theater and streamed online, featured John Fernandez, director of ESI; Dava Newman, director of the Media Lab; Tony McGuinness, a musician with the group Above and Beyond; and Anna Johnson, the sustainability and environment officer at Involved Group, an organization dedicated to embedding sustainability in business operations in the arts and culture fields.

      Fernandez pointed out in opening the discussion that when it comes to influencing people’s attitudes and behavior, changes tend to come about not just through information from a particular field, but rather from a whole culture. “We started thinking about how we might work with artists, how to have scientists and engineers, inventors, and designers working with artists on the challenges that we really need to face,” he said.

      Dealing with the climate change issue, he said, “is not about 2050 or 2100. This is about 2030. This is about this decade. This is about the next two or three years, really shifting that curve” to lowering the world’s greenhouse gas emissions. “It’s not going to be done just with science and engineering,” he added. “It’s got to be done with artists and business and everyone else. It’s not only ‘all of the above’ solutions, it’s ‘all of the above’ people, coming together to solve this problem.”

      Newman, who is also a professor in MIT’s Department of Aeronautics and Astronautics and has served as a NASA deputy administrator, said that while scientists and engineers can produce vast amounts of useful data that clearly demonstrate the dramatic changes the Earth’s climate is undergoing, communicating that information effectively is often a challenge for these specialists. “That data is just the data, but that doesn’t change the hearts and minds,” she said.

      “As scientists, having the data from our satellites, looking down, but also flying airplanes into the atmosphere, … we have the sensors, and then what can we do with it all? … How do we change human behavior? That’s the part I don’t know how to do,” Newman said. “I can have the technology, I can get precision measurements, I can study it, but really at the end of the day, we have to change human behavior, and that is so hard.”

      And that’s where the world of art and music can play a part, she said. “The best way that I know how to do it is with artistic experiences. You can have one moving experience and when you wake up tomorrow, maybe you’re going to do something a little different.” To help generate the compassion and empathy needed to affect behavior positively, she said, “that’s where we turn to the storytellers. We turn to the visionaries.”

      McGuinness, whose electronic music trio has performed for millions of people around the world, said that his own awareness of the urgency of the climate issue came from his passion for scuba diving, and the dramatic changes he has seen over the last two decades. In diving at a coral reef off Palau in the South Pacific, he returned to what had been a lush, brightly colored ecosystem, and found that “immediately when you put your face under the water, you’re looking at the surface of the moon. It was a horrible shock to see this.”

      After this and other similar diving experiences, he said, “I just came away shocked and stunned,” and realizing the kinds of underwater experiences he had enjoyed would no longer exist for his children. After reading more on the subject of global warming,  “that really sort of tipped me over the edge. And I was like, this is probably the most important thing for living beings now. And that’s sort of where I’ve remained ever since.”

      While his group Above and Beyond has performed one song specifically related to global warming, he doesn’t expect that to be the most impactful way of using their influence. Rather, they’re trying to lead by example, he said, by paying more attention to everything from the supply chains of the merchandise sold at concerts to the emissions generated by travel to the concerts. They’re also being selective about concert venues and making an effort to find performance spaces that are making a significant effort to curb their emissions.

      “If people start voting with their wallets,” McGuinness said, “and there are companies that are doing better than others and are doing the right thing, maybe it’ll catch on. I guess that’s what we can hope for.”

      Understanding these kinds of issues, involving supply chains, transportation, and facilities associated within the music industry, has been the focus of much of Johnson’s work, through the organization Involved Group, which has entered into a collaboration with MIT through the Environmental Solutions Initiative. “It’s these kinds of novel partnerships that have so much potential to catalyze the change that we need to see at an incredible pace,” she said. Already, her group has worked with MIT on mapping out where emissions occur throughout the various aspects of the music industry.

      At a recent music festival in London, she said, the group interviewed hundreds of participants, including audience members, band members, and the crew. “We explored people’s level of awareness of the issues around climate change and environmental degradation,” she said. “And what was really interesting was that there was clearly a lot of awareness of the issue across those different stakeholders, and what felt like a real, genuine level of concern and also of motivation, to want to deepen their understanding of what their contribution on a personal level really meant.”

      Working together across the boundaries of different disciplines and areas of expertise could be crucial to winning the battle against global warming, Newman said. “That’s usually how breakthroughs work,” she said. “If we’re really looking to have impact, it’s going to be from teams of people who are trained across the disciplines.” She pointed out that 90 percent of MIT students are also musicians: “It does go together!” she said. “I think going forward, we have to create new academia, new opportunities that are truly multidisciplinary.” More

    • 150 Shares129 Views

      in Energy

      Timber or steel? Study helps builders reduce carbon footprint of truss structures

      by

      Buildings are a big contributor to global warming, not just in their ongoing operations but in the materials used in their construction. Truss structures — those crisscross arrays of diagonal struts used throughout modern construction, in everything from antenna towers to support beams for large buildings — are typically made of steel or wood or a combination of both. But little quantitative research has been done on how to pick the right materials to minimize these structures’ contribution global warming.

      The “embodied carbon” in a construction material includes the fuel used in the material’s production (for mining and smelting steel, for example, or for felling and processing trees) and in transporting the materials to a site. It also includes the equipment used for the construction itself.

      Now, researchers at MIT have done a detailed analysis and created a set of computational tools to enable architects and engineers to design truss structures in a way that can minimize their embodied carbon while maintaining all needed properties for a given building application. While in general wood produces a much lower carbon footprint, using steel in places where its properties can provide maximum benefit can provide an optimized result, they say.

      The analysis is described in a paper published today in the journal Engineering Structures, by graduate student Ernest Ching and MIT assistant professor of civil and environmental engineering Josephine Carstensen.

      “Construction is a huge greenhouse gas emitter that has kind of been flying under the radar for the past decades,” says Carstensen. But in recent years building designers “are starting to be more focused on how to not just reduce the operating energy associated with building use, but also the important carbon associated with the structure itself.” And that’s where this new analysis comes in.

      The two main options in reducing the carbon emissions associated with truss structures, she says, are substituting materials or changing the structure. However, there has been “surprisingly little work” on tools to help designers figure out emissions-minimizing strategies for a given situation, she says.

      The new system makes use of a technique called topology optimization, which allows for the input of basic parameters, such as the amount of load to be supported and the dimensions of the structure, and can be used to produce designs optimized for different characteristics, such as weight, cost, or, in this case, global warming impact.

      Wood performs very well under forces of compression, but not as well as steel when it comes to tension — that is, a tendency to pull the structure apart. Carstensen says that in general, wood is far better than steel in terms of embedded carbon, so “especially if you have a structure that doesn’t have any tension, then you should definitely only use timber” in order to minimize emissions. One tradeoff is that “the weight of the structure is going to be bigger than it would be with steel,” she says.

      The tools they developed, which were the basis for Ching’s master’s thesis, can be applied at different stages, either in the early planning phase of a structure, or later on in the final stages of a design.

      As an exercise, the team developed a proposal for reengineering several trusses using these optimization tools, and demonstrated that a significant savings in embodied greenhouse gas emissions could be achieved with no loss of performance. While they have shown improvements of at least 10 percent can be achieved, she says those estimates are “not exactly apples to apples” and likely savings could actually be two to three times that.

      “It’s about choosing materials more smartly,” she says, for the specifics of a given application. Often in existing buildings “you will have timber where there’s compression, and where that makes sense, and then it will have really skinny steel members, in tension, where that makes sense. And that’s also what we see in our design solutions that are suggested, but perhaps we can see it even more clearly.” The tools are not ready for commercial use though, she says, because they haven’t yet added a user interface.

      Carstensen sees a trend to increasing use of timber in large construction, which represents an important potential for reducing the world’s overall carbon emissions. “There’s a big interest in the construction industry in mass timber structures, and this speaks right into that area. So, the hope is that this would make inroads into the construction business and actually make a dent in that very large contribution to greenhouse gas emissions.” More

    • 75 Shares129 Views

      in Environment

      Nanograins make for a seismic shift

      by

      In Earth’s crust, tectonic blocks slide and grind past each other like enormous ships loosed from anchor. Earthquakes are generated along these fault zones when enough stress builds for a block to stick, then suddenly slip.

      These slips can be aided by several factors that reduce friction within a fault zone, such as hotter temperatures or pressurized gases that can separate blocks like pucks on an air-hockey table. The decreasing friction enables one tectonic block to accelerate against the other until it runs out of energy. Seismologists have long believed this kind of frictional instability can explain how all crustal earthquakes start. But that might not be the whole story.

      In a study published today in Nature Communications, scientists Hongyu Sun and Matej Pec, from MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS), find that ultra-fine-grained crystals within fault zones can behave like low-viscosity fluids. The finding offers an alternative explanation for the instability that leads to crustal earthquakes. It also suggests a link between quakes in the crust and other types of temblors that occur deep in the Earth.

      Nanograins are commonly found in rocks from seismic environments along the smooth surface of “fault mirrors.” These polished, reflective rock faces betray the slipping, sliding forces of past earthquakes. However, it was unclear whether the crystals caused quakes or were merely formed by them.

      To better characterize how these crystals behaved within a fault, the researchers used a planetary ball milling machine to pulverize granite rocks into particles resembling those found in nature. Like a super-powered washing machine filled with ceramic balls, the machine pounded the rock until all its crystals were about 100 nanometers in width, each grain 1/2,000 the size of an average grain of sand.

      After packing the nanopowder into postage-stamp sized cylinders jacketed in gold, the researchers then subjected the material to stresses and heat, creating laboratory miniatures of real fault zones. This process enabled them to isolate the effect of the crystals from the complexity of other factors involved in an actual earthquake.

      The researchers report that the crystals were extremely weak when shearing was initiated — an order of magnitude weaker than more common microcrystals. But the nanocrystals became significantly stronger when the deformation rate was accelerated. Pec, professor of geophysics and the Victor P. Starr Career Development Chair, compares this characteristic, called “rate-strengthening,” to stirring honey in a jar. Stirring the honey slowly is easy, but becomes more difficult the faster you stir.

      The experiment suggests something similar happens in fault zones. As tectonic blocks accelerate past each other, the crystals gum things up between them like honey stirred in a seismic pot.

      Sun, the study’s lead author and EAPS graduate student, explains that their finding runs counter to the dominant frictional weakening theory of how earthquakes start. That theory would predict surfaces of a fault zone have material that gets weaker as the fault block accelerates, and friction should be decreasing. The nanocrystals did just the opposite. However, the crystals’ intrinsic weakness could mean that when enough of them accumulate within a fault, they can give way, causing an earthquake.

      “We don’t totally disagree with the old theorem, but our study really opens new doors to explain the mechanisms of how earthquakes happen in the crust,” Sun says.

      The finding also suggests a previously unrecognized link between earthquakes in the crust and the earthquakes that rumble hundreds of kilometers beneath the surface, where the same tectonic dynamics aren’t at play. That deep, there are no tectonic blocks to grind against each other, and even if there were, the immense pressure would prevent the type of quakes observed in the crust that necessitate some dilatancy and void creation.

      “We know that earthquakes happen all the way down to really big depths where this motion along a frictional fault is basically impossible,” says Pec. “And so clearly, there must be different processes that allow for these earthquakes to happen.”

      Possible mechanisms for these deep-Earth tremors include “phase transitions” which occur due to atomic re-arrangement in minerals and are accompanied by a volume change, and other kinds of metamorphic reactions, such as dehydration of water-bearing minerals, in which the released fluid is pumped through pores and destabilizes a fault. These mechanisms are all characterized by a weak, rate-strengthening layer.

      If weak, rate-strengthening nanocrystals are abundant in the deep Earth, they could present another possible mechanism, says Pec. “Maybe crustal earthquakes are not a completely different beast than the deeper earthquakes. Maybe they have something in common.” More

    • 125 Shares199 Views

      in Energy

      At UN climate change conference, trying to “keep 1.5 alive”

      by

      After a one-year delay caused by the Covid-19 pandemic, negotiators from nearly 200 countries met this month in Glasgow, Scotland, at COP26, the United Nations climate change conference, to hammer out a new global agreement to reduce greenhouse gas emissions and prepare for climate impacts. A delegation of approximately 20 faculty, staff, and students from MIT was on hand to observe the negotiations, share and conduct research, and launch new initiatives.

      On Saturday, Nov. 13, following two weeks of negotiations in the cavernous Scottish Events Campus, countries’ representatives agreed to the Glasgow Climate Pact. The pact reaffirms the goal of the 2015 Paris Agreement “to pursue efforts” to limit the global average temperature increase to 1.5 degrees Celsius above preindustrial levels, and recognizes that achieving this goal requires “reducing global carbon dioxide emissions by 45 percent by 2030 relative to the 2010 level and to net zero around mid-century.”

      “On issues like the need to reach net-zero emissions, reduce methane pollution, move beyond coal power, and tighten carbon accounting rules, the Glasgow pact represents some meaningful progress, but we still have so much work to do,” says Maria Zuber, MIT’s vice president for research, who led the Institute’s delegation to COP26. “Glasgow showed, once again, what a wicked complex problem climate change is, technically, economically, and politically. But it also underscored the determination of a global community of people committed to addressing it.”

      An “ambition gap”

      Both within the conference venue and at protests that spilled through the streets of Glasgow, one rallying cry was “keep 1.5 alive.” Alok Sharma, who was appointed by the UK government to preside over COP26, said in announcing the Glasgow pact: “We can now say with credibility that we have kept 1.5 degrees alive. But, its pulse is weak and it will only survive if we keep our promises and translate commitments into rapid action.”

      In remarks delivered during the first week of the conference, Sergey Paltsev, deputy director of MIT’s Joint Program on the Science and Policy of Global Change, presented findings from the latest MIT Global Change Outlook, which showed a wide gap between countries’ nationally determined contributions (NDCs) — the UN’s term for greenhouse gas emissions reduction pledges — and the reductions needed to put the world on track to meet the goals of the Paris Agreement and, now, the Glasgow pact.

      Pointing to this ambition gap, Paltsev called on all countries to do more, faster, to cut emissions. “We could dramatically reduce overall climate risk through more ambitious policy measures and investments,” says Paltsev. “We need to employ an integrated approach of moving to zero emissions in energy and industry, together with sustainable development and nature-based solutions, simultaneously improving human well-being and providing biodiversity benefits.”

      Finalizing the Paris rulebook

      A key outcome of COP26 (COP stands for “conference of the parties” to the UN Framework Convention on Climate Change, held for the 26th time) was the development of a set of rules to implement Article 6 of the Paris Agreement, which provides a mechanism for countries to receive credit for emissions reductions that they finance outside their borders, and to cooperate by buying and selling emissions reductions on international carbon markets.

      An agreement on this part of the Paris “rulebook” had eluded negotiators in the years since the Paris climate conference, in part because negotiators were concerned about how to prevent double-counting, wherein both buyers and sellers would claim credit for the emissions reductions.

      Michael Mehling, the deputy director of MIT’s Center for Energy and Environmental Policy Research (CEEPR) and an expert on international carbon markets, drew on a recent CEEPR working paper to describe critical negotiation issues under Article 6 during an event at the conference on Nov. 10 with climate negotiators and private sector representatives.

      He cited research that finds that Article 6, by leveraging the cost-efficiency of global carbon markets, could cut in half the cost that countries would incur to achieve their nationally determined contributions. “Which, seen from another angle, means you could double the ambition of these NDCs at no additional cost,” Mehling noted in his talk, adding that, given the persistent ambition gap, “any such opportunity is bitterly needed.”

      Andreas Haupt, a graduate student in the Institute for Data, Systems, and Society, joined MIT’s COP26 delegation to follow Article 6 negotiations. Haupt described the final days of negotiations over Article 6 as a “roller coaster.” Once negotiators reached an agreement, he says, “I felt relieved, but also unsure how strong of an effect the new rules, with all their weaknesses, will have. I am curious and hopeful regarding what will happen in the next year until the next large-scale negotiations in 2022.”

      Nature-based climate solutions

      World leaders also announced new agreements on the sidelines of the formal UN negotiations. One such agreement, a declaration on forests signed by more than 100 countries, commits to “working collectively to halt and reverse forest loss and land degradation by 2030.”

      A team from MIT’s Environmental Solutions Initiative (ESI), which has been working with policymakers and other stakeholders on strategies to protect tropical forests and advance other nature-based climate solutions in Latin America, was at COP26 to discuss their work and make plans for expanding it.

      Marcela Angel, a research associate at ESI, moderated a panel discussion featuring John Fernández, professor of architecture and ESI’s director, focused on protecting and enhancing natural carbon sinks, particularly tropical forests such as the Amazon that are at risk of deforestation, forest degradation, and biodiversity loss.

      “Deforestation and associated land use change remain one of the main sources of greenhouse gas emissions in most Amazonian countries, such as Brazil, Peru, and Colombia,” says Angel. “Our aim is to support these countries, whose nationally determined contributions depend on the effectiveness of policies to prevent deforestation and promote conservation, with an approach based on the integration of targeted technology breakthroughs, deep community engagement, and innovative bioeconomic opportunities for local communities that depend on forests for their livelihoods.”

      Energy access and renewable energy

      Worldwide, an estimated 800 million people lack access to electricity, and billions more have only limited or erratic electrical service. Providing universal access to energy is one of the UN’s sustainable development goals, creating a dual challenge: how to boost energy access without driving up greenhouse gas emissions.

      Rob Stoner, deputy director for science and technology of the MIT Energy Initiative (MITEI), and Ignacio Pérez-Arriaga, a visiting professor at the Sloan School of Management, attended COP26 to share their work as members of the Global Commission to End Energy Poverty, a collaboration between MITEI and the Rockefeller Foundation. It brings together global energy leaders from industry, the development finance community, academia, and civil society to identify ways to overcome barriers to investment in the energy sectors of countries with low energy access.

      The commission’s work helped to motivate the formation, announced at COP26 on Nov. 2, of the Global Energy Alliance for People and Planet, a multibillion-dollar commitment by the Rockefeller and IKEA foundations and Bezos Earth Fund to support access to renewable energy around the world.

      Another MITEI member of the COP26 delegation, Martha Broad, the initiative’s executive director, spoke about MIT research to inform the U.S. goal of scaling offshore wind energy capacity from approximately 30 megawatts today to 30 gigawatts by 2030, including significant new capacity off the coast of New England.

      Broad described research, funded by MITEI member companies, on a coating that can be applied to the blades of wind turbines to prevent icing that would require the turbines’ shutdown; the use of machine learning to inform preventative turbine maintenance; and methodologies for incorporating the effects of climate change into projections of future wind conditions to guide wind farm siting decisions today. She also spoke broadly about the need for public and private support to scale promising innovations.

      “Clearly, both the public sector and the private sector have a role to play in getting these technologies to the point where we can use them in New England, and also where we can deploy them affordably for the developing world,” Broad said at an event sponsored by America Is All In, a coalition of nonprofit and business organizations.

      Food and climate alliance

      Food systems around the world are increasingly at risk from the impacts of climate change. At the same time, these systems, which include all activities from food production to consumption and food waste, are responsible for about one-third of the human-caused greenhouse gas emissions warming the planet.

      At COP26, MIT’s Abdul Latif Jameel Water and Food Systems Lab announced the launch of a new alliance to drive research-based innovation that will make food systems more resilient and sustainable, called the Food and Climate Systems Transformation (FACT) Alliance. With 16 member institutions, the FACT Alliance will better connect researchers to farmers, food businesses, policymakers, and other food systems stakeholders around the world.

      Looking ahead

      By the end of 2022, the Glasgow pact asks countries to revisit their nationally determined contributions and strengthen them to bring them in line with the temperature goals of the Paris Agreement. The pact also “notes with deep regret” the failure of wealthier countries to collectively provide poorer countries $100 billion per year in climate financing that they pledged in 2009 to begin in 2020.

      These and other issues will be on the agenda for COP27, to be held in Sharm El-Sheikh, Egypt, next year.

      “Limiting warming to 1.5 degrees is broadly accepted as a critical goal to avoiding worsening climate consequences, but it’s clear that current national commitments will not get us there,” says ESI’s Fernández. “We will need stronger emissions reductions pledges, especially from the largest greenhouse gas emitters. At the same time, expanding creativity, innovation, and determination from every sector of society, including research universities, to get on with real-world solutions is essential. At Glasgow, MIT was front and center in energy systems, cities, nature-based solutions, and more. The year 2030 is right around the corner so we can’t afford to let up for one minute.” More