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      in Energy

      Moving past the Iron Age

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      MIT graduate student Sydney Rose Johnson has never seen the steel mills in central India. She’s never toured the American Midwest’s hulking steel plants or the mini mills dotting the Mississippi River. But in the past year, she’s become more familiar with steel production than she ever imagined.

      A fourth-year dual degree MBA and PhD candidate in chemical engineering and a graduate research assistant with the MIT Energy Initiative (MITEI) as well as a 2022-23 Shell Energy Fellow, Johnson looks at ways to reduce carbon dioxide (CO2) emissions generated by industrial processes in hard-to-abate industries. Those include steel.

      Almost every aspect of infrastructure and transportation — buildings, bridges, cars, trains, mass transit — contains steel. The manufacture of steel hasn’t changed much since the Iron Age, with some steel plants in the United States and India operating almost continually for more than a century, their massive blast furnaces re-lined periodically with carbon and graphite to keep them going.

      According to the World Economic Forum, steel demand is projected to increase 30 percent by 2050, spurred in part by population growth and economic development in China, India, Africa, and Southeast Asia.

      The steel industry is among the three biggest producers of CO2 worldwide. Every ton of steel produced in 2020 emitted, on average, 1.89 tons of CO2 into the atmosphere — around 8 percent of global CO2 emissions, according to the World Steel Association.

      A combination of technical strategies and financial investments, Johnson notes, will be needed to wrestle that 8 percent figure down to something more planet-friendly.

      Johnson’s thesis focuses on modeling and analyzing ways to decarbonize steel. Using data mined from academic and industry sources, she builds models to calculate emissions, costs, and energy consumption for plant-level production.

      “I optimize steel production pathways using emission goals, industry commitments, and cost,” she says. Based on the projected growth of India’s steel industry, she applies this approach to case studies that predict outcomes for some of the country’s thousand-plus factories, which together have a production capacity of 154 million metric tons of steel. For the United States, she looks at the effect of Inflation Reduction Act (IRA) credits. The 2022 IRA provides incentives that could accelerate the steel industry’s efforts to minimize its carbon emissions.

      Johnson compares emissions and costs across different production pathways, asking questions such as: “If we start today, what would a cost-optimal production scenario look like years from now? How would it change if we added in credits? What would have to happen to cut 2005 levels of emissions in half by 2030?”

      “My goal is to gain an understanding of how current and emerging decarbonization strategies will be integrated into the industry,” Johnson says.

      Grappling with industrial problems

      Growing up in Marietta, Georgia, outside Atlanta, the closest she ever came to a plant of any kind was through her father, a chemical engineer working in logistics and procuring steel for an aerospace company, and during high school, when she spent a semester working alongside chemical engineers tweaking the pH of an anti-foaming agent.

      At Kennesaw Mountain High School, a STEM magnet program in Cobb County, students devote an entire semester of their senior year to an internship and research project.

      Johnson chose to work at Kemira Chemicals, which develops chemical solutions for water-intensive industries with a focus on pulp and paper, water treatment, and energy systems.

      “My goal was to understand why a polymer product was falling out of suspension — essentially, why it was less stable,” she recalls. She learned how to formulate a lab-scale version of the product and conduct tests to measure its viscosity and acidity. Comparing the lab-scale and regular product results revealed that acidity was an important factor. “Through conversations with my mentor, I learned this was connected with the holding conditions, which led to the product being oxidized,” she says. With the anti-foaming agent’s problem identified, steps could be taken to fix it.

      “I learned how to apply problem-solving. I got to learn more about working in an industrial environment by connecting with the team in quality control as well as with R&D and chemical engineers at the plant site,” Johnson says. “This experience confirmed I wanted to pursue engineering in college.”

      As an undergraduate at Stanford University, she learned about the different fields — biotechnology, environmental science, electrochemistry, and energy, among others — open to chemical engineers. “It seemed like a very diverse field and application range,” she says. “I was just so intrigued by the different things I saw people doing and all these different sets of issues.”

      Turning up the heat

      At MIT, she turned her attention to how certain industries can offset their detrimental effects on climate.

      “I’m interested in the impact of technology on global communities, the environment, and policy. Energy applications affect every field. My goal as a chemical engineer is to have a broad perspective on problem-solving and to find solutions that benefit as many people, especially those under-resourced, as possible,” says Johnson, who has served on the MIT Chemical Engineering Graduate Student Advisory Board, the MIT Energy and Climate Club, and is involved with diversity and inclusion initiatives.

      The steel industry, Johnson acknowledges, is not what she first imagined when she saw herself working toward mitigating climate change.

      “But now, understanding the role the material has in infrastructure development, combined with its heavy use of coal, has illuminated how the sector, along with other hard-to-abate industries, is important in the climate change conversation,” Johnson says.

      Despite the advanced age of many steel mills, some are quite energy-efficient, she notes. Yet these operations, which produce heat upwards of 3,000 degrees Fahrenheit, are still emission-intensive.

      Steel is made from iron ore, a mixture of iron, oxygen, and other minerals found on virtually every continent, with Brazil and Australia alone exporting millions of metric tons per year. Commonly based on a process dating back to the 19th century, iron is extracted from the ore through smelting — heating the ore with blast furnaces until the metal becomes spongy and its chemical components begin to break down.

      A reducing agent is needed to release the oxygen trapped in the ore, transforming it from its raw form to pure iron. That’s where most emissions come from, Johnson notes.

      “We want to reduce emissions, and we want to make a cleaner and safer environment for everyone,” she says. “It’s not just the CO2 emissions. It’s also sometimes NOx and SOx [nitrogen oxides and sulfur oxides] and air pollution particulate matter at some of these production facilities that can affect people as well.”

      In 2020, the International Energy Agency released a roadmap exploring potential technologies and strategies that would make the iron and steel sector more compatible with the agency’s vision of increased sustainability. Emission reductions can be accomplished with more modern technology, the agency suggests, or by substituting the fuels producing the immense heat needed to process ore. Traditionally, the fuels used for iron reduction have been coal and natural gas. Alternative fuels include clean hydrogen, electricity, and biomass.

      Using the MITEI Sustainable Energy System Analysis Modeling Environment (SESAME), Johnson analyzes various decarbonization strategies. She considers options such as switching fuel for furnaces to hydrogen with a little bit of natural gas or adding carbon-capture devices. The models demonstrate how effective these tactics are likely to be. The answers aren’t always encouraging.

      “Upstream emissions can determine how effective the strategies are,” Johnson says. Charcoal derived from forestry biomass seemed to be a promising alternative fuel, but her models showed that processing the charcoal for use in the blast furnace limited its effectiveness in negating emissions.

      Despite the challenges, “there are definitely ways of moving forward,” Johnson says. “It’s been an intriguing journey in terms of understanding where the industry is at. There’s still a long way to go, but it’s doable.”

      Johnson is heartened by the steel industry’s efforts to recycle scrap into new steel products and incorporate more emission-friendly technologies and practices, some of which result in significantly lower CO2 emissions than conventional production.

      A major issue is that low-carbon steel can be more than 50 percent more costly than conventionally produced steel. “There are costs associated with making the transition, but in the context of the environmental implications, I think it’s well worth it to adopt these technologies,” she says.

      After graduation, Johnson plans to continue to work in the energy field. “I definitely want to use a combination of engineering knowledge and business knowledge to work toward mitigating climate change, potentially in the startup space with clean technology or even in a policy context,” she says. “I’m interested in connecting the private and public sectors to implement measures for improving our environment and benefiting as many people as possible.” More

    • 75 Shares149 Views

      in Environment

      Q&A: A blueprint for sustainable innovation

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      Atacama Biomaterials is a startup combining architecture, machine learning, and chemical engineering to create eco-friendly materials with multiple applications. Passionate about sustainable innovation, its co-founder Paloma Gonzalez-Rojas SM ’15, PhD ’21 highlights here how MIT has supported the project through several of its entrepreneurship initiatives, and reflects on the role of design in building a holistic vision for an expanding business.

      Q: What role do you see your startup playing in the sustainable materials space?

      A: Atacama Biomaterials is a venture dedicated to advancing sustainable materials through state-of-the-art technology. With my co-founder Jose Tomas Dominguez, we have been working on developing our technology since 2019. We initially started the company in 2020 under another name and received Sandbox funds the next year. In 2021, we went through The Engine’s accelerator, Blueprint, and changed our name to Atacama Biomaterials in 2022 during the MITdesignX program. 

      This technology we have developed allows us to create our own data and material library using artificial intelligence and machine learning, and serves as a platform applicable to various industries horizontally — biofuels, biological drugs, and even mining. Vertically, we produce inexpensive, regionally sourced, and environmentally friendly bio-based polymers and packaging — that is, naturally compostable plastics as a flagship product, along with AI products.

      Q: What motivated you to venture into biomaterials and found Atacama?

      A: I’m from Chile, a country with a beautiful, rich geography and nature where we can see all the problems stemming from industry, waste management, and pollution. We named our company Atacama Biomaterials because the Atacama Desert in Chile — one of the places where you can best see the stars in the world — is becoming a plastic dump, as many other places on Earth. I care deeply about sustainability, and I have an emotional attachment to stop these problems. Considering that manufacturing accounts for 29 percent of global carbon emissions, it is clear that sustainability has a role in how we define technology and entrepreneurship, as well as a socio-economic dimension.

      When I first came to MIT, it was to develop software in the Department of Architecture’s Design and Computation Group, with MIT professors Svafa Gronfeldt as co-advisor and Regina Barzilay as committee member. During my PhD, I studied machine-learning methods simulating pedestrian motion to understand how people move in space. In my work, I would use lots of plastics for 3D printing and I couldn’t stop thinking about sustainability and climate change, so I reached out to material science and mechanical engineering professors to look into biopolymers and degradable bio-based materials. This is how I met my co-founder, as we were both working with MIT Professor Neil Gershenfeld. Together, we were part of one of the first teams in the world to 3D print wood fibers, which is difficult — it’s slow and expensive — and quickly pivoted to sustainable packaging. 

      I then won a fellowship from MCSC [the MIT Climate and Sustainability Consortium], which gave me freedom to explore further, and I eventually got a postdoc in MIT chemical engineering, guided by MIT Professor Gregory Rutledge, a polymer physicist. This was unexpected in my career path. Winning Nucleate Eco Track 2022 and the MITdesignX Innovation Award in 2022 profiled Atacama Biomaterials as one of the rising startups in Boston’s biotechnology and climate-tech scene.

      Q: What is your process to develop new biomaterials?

      A: My PhD research, coupled with my background in material development and molecular dynamics, sparked the realization that principles I studied simulating pedestrian motion could also apply to molecular engineering. This connection may seem unconventional, but for me, it was a natural progression. Early in my career, I developed an intuition for materials, understanding their mechanics and physics.

      Using my experience and skills, and leveraging machine learning as a technology jump, I applied a similar conceptual framework to simulate the trajectories of molecules and find potential applications in biomaterials. Making that parallel and shift was amazing. It allowed me to optimize a state-of-the-art molecular dynamic software to run twice as fast as more traditional technologies through my algorithm presented at the International Conference of Machine Learning this year. This is very important, because this kind of simulation usually takes a week, so narrowing it down to two days has major implications for scientists and industry, in material science, chemical engineering, computer science and related fields. Such work greatly influenced the foundation of Atacama Biomaterials, where we developed our own AI to deploy our materials. In an effort to mitigate the environmental impact of manufacturing, Atacama is targeting a 16.7 percent reduction in carbon dioxide emissions associated with the manufacturing process of its polymers, through the use of renewable energy. 

      Another thing is that I was trained as an architect in Chile, and my degree had a design component. I think design allows me to understand problems at a very high level, and how things interconnect. It contributed to developing a holistic vision for Atacama, because it allowed me to jump from one technology or discipline to another and understand broader applications on a conceptual level. Our design approach also meant that sustainability came to the center of our work from the very beginning, not just a plus or an added cost.

      Q: What was the role of MITdesignX in Atacama’s development?

      A: I have known Svafa Grönfeldt, MITdesignX’s faculty director, for almost six years. She was the co-advisor of my PhD, and we had a mentor-mentee relationship. I admire the fact that she created a space for people interested in business and entrepreneurship to grow within the Department of Architecture. She and Executive Director Gilad Rosenzweig gave us fantastic advice, and we received significant support from mentors. For example, Daniel Tsai helped us with intellectual property, including a crucial patent for Atacama. And we’re still in touch with the rest of the cohort. I really like this “design your company” approach, which I find quite unique, because it gives us the opportunity to reflect on who we want to be as designers, technologists, and entrepreneurs. Studying user insights also allowed us to understand the broad applicability of our research, and align our vision with market demands, ultimately shaping Atacama into a company with a holistic perspective on sustainable material development.

      Q: How does Atacama approach scaling, and what are the immediate next steps for the company?

      A: When I think about accomplishing our vision, I feel really inspired by my 3-year-old daughter. I want her to experience a world with trees and wildlife when she’s 100 years old, and I hope Atacama will contribute to such a future.

      Going back to the designer’s perspective, we designed the whole process holistically, from feedstock to material development, incorporating AI and advanced manufacturing. Having proved that there is a demand for the materials we are developing, and having tested our products, manufacturing process, and technology in critical environments, we are now ready to scale. Our level of technology-readiness is comparable to the one used by NASA (level 4).

      We have proof of concept: a biodegradable and recyclable packaging material which is cost- and energy-efficient as a clean energy enabler in large-scale manufacturing. We have received pre-seed funding, and are sustainably scaling by taking advantage of available resources around the world, like repurposing machinery from the paper industry. As presented in the MIT Industrial Liaison and STEX Program’s recent Sustainability Conference, unlike our competitors, we have cost-parity with current packaging materials, as well as low-energy processes. And we also proved the demand for our products, which was an important milestone. Our next steps involve strategically expanding our manufacturing capabilities and research facilities and we are currently evaluating building a factory in Chile and establishing an R&D lab plus a manufacturing plant in the U.S. More

    • 88 Shares159 Views

      in Energy

      Meeting the clean energy needs of tomorrow

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      Yuri Sebregts, chief technology officer at Shell, succinctly laid out the energy dilemma facing the world over the rest of this century. On one hand, demand for energy is quickly growing as countries in the developing world modernize and the global population grows, with 100 gigajoules of energy per person needed annually to enable quality-of-life benefits and industrialization around the globe. On the other, traditional energy sources are quickly warming the planet, with the world already seeing the devastating effects of increasingly frequent extreme weather events. 

      While the goals of energy security and energy sustainability are seemingly at odds with one another, the two must be pursued in tandem, Sebregts said during his address at the MIT Energy Initiative Fall Colloquium.

      “An environmentally sustainable energy system that isn’t also a secure energy system is not sustainable,” Sebregts said. “And conversely, a secure energy system that is not environmentally sustainable will do little to ensure long-term energy access and affordability. Therefore, security and sustainability must go hand-in-hand. You can’t trade off one for the other.”

      Sebregts noted that there are several potential pathways to help strike this balance, including investments in renewable energy sources, the use of carbon offsets, and the creation of more efficient tools, products, and processes. However, he acknowledged that meeting growing energy demands while minimizing environmental impacts is a global challenge requiring an unprecedented level of cooperation among countries and corporations across the world. 

      “At Shell, we recognize that this will require a lot of collaboration between governments, businesses, and civil society,” Sebregts said. “That’s not always easy.”

      Global conflict and global warming

      In 2021, Sebregts noted, world leaders gathered in Glasgow, Scotland and collectively promised to deliver on the “stretch goal” of the 2015 Paris Agreement, which would limit global warming to 1.5 degrees Celsius — a level that scientists believe will help avoid the worst potential impacts of climate change. But, just a few months later, Russia invaded Ukraine, resulting in chaos in global energy markets and illustrating the massive impact that geopolitical friction can have on efforts to reduce carbon emissions.

      “Even though global volatility has been a near constant of this century, the situation in Ukraine is proving to be a turning point,” Sebregts said. “The stress it placed on the global supply of energy, food, and other critical materials was enormous.”

      In Europe, Sebregts noted, countries affected by the loss of Russia’s natural gas supply began importing from the Middle East and the United States. This, in turn, drove up prices. While this did result in some efforts to limit energy use, such as Europeans lowering their thermostats in the winter, it also caused some energy buyers to turn to coal. For instance, the German government approved additional coal mining to boost its energy security — temporarily reversing a decades-long transition away from the fuel. To put this into wider perspective, in a single quarter, China increased its coal generation capacity by as much as Germany had reduced its own over the previous 20 years.

      The promise of electrification

      Sebregts noted the strides being made toward electrification, which is expected to have a significant impact on global carbon emissions. To meet net-zero emissions (the point at which humans are adding no more carbon to the atmosphere than they are removing) by 2050, the share of electricity as a portion of total worldwide energy consumption must reach 37 percent by 2030, up from 20 percent in 2020, Sebregts said.

      He pointed out that Shell has become one of the world’s largest electric vehicle charging companies, with more than 30,000 public charge points. By 2025, that number will increase to 70,000, and it is expected to soar to 200,000 by 2030. While demand and infrastructure for electric vehicles are growing, Sebregts said that the “real needle-mover” will be industrial electrification, especially in so-called “hard-to-abate” sectors.

      This progress will depend heavily on global cooperation — Sebregts pointed out that China dominates the international market for many rare elements that are key components of electrification infrastructure. “It shouldn’t be a surprise that the political instability, shifting geopolitical tensions, and environmental and social governance issues are significant risks for the energy transition,” he said. “It is imperative that we reduce, control, and mitigate these risks as much as possible.”

      Two possible paths

      For decades, Sebregts said, Shell has created scenarios to help senior managers think through the long-term challenges facing the company. While Sebregts stressed that these scenarios are not predictions, they do take into account real-world conditions, and they are meant to give leaders the opportunity to grapple with plausible situations.

      With this in mind, Sebregts outlined Shell’s most recent Energy Security Scenarios, describing the potential future consequences of attempts to balance growing energy demand with sustainability — scenarios that envision vastly different levels of global cooperation, with huge differences in projected results. 

      The first scenario, dubbed “Archipelagos,” imagines countries pursuing energy security through self-interest — a fragmented, competitive process that would result in a global temperature increase of 2.2 degrees Celsius by the end of this century. The second scenario, “Sky 2050,” envisions countries around the world collaborating to change the energy system for their mutual benefit. This more optimistic scenario would see a much lower global temperature increase of 1.2 C by 2100.

      “The good news is that in both scenarios, the world is heading for net-zero emissions at some point,” Sebregts said. “The difference is a question of when it gets there. In Sky 2050, it is the middle of the century. In Archipelagos, it is early in the next century.”

      On the other hand, Sebregts added, the average global temperature will increase by more than 1.5 C for some period of time in either scenario. But, in the Archipelagos scenario, this overshoot will be much larger, and will take much longer to come down. “So, two very different futures,” Sebregts said. “Two very different worlds.”

      The work ahead

      Questioned about the costs of transitioning to a net-zero energy ecosystem, Sebregts said that it is “very hard” to provide an accurate answer. “If you impose an additional constraint … you’re going to have to add some level of cost,” he said. “But then, of course, there’s 30 years of technology development pathway that might counteract some of that.”

      In some cases, such as air travel, Sebregts said, it will likely remain impractical to either rely on electrification or sequester carbon at the source of emission. Direct air capture (DAC) methods, which mechanically pull carbon directly from the atmosphere, will have a role to play in offsetting these emissions, he said. Sebregts predicted that the price of DAC could come down significantly by the middle of this century. “I would venture that a price of $200 to $250 a ton of CO2 by 2050 is something that the world would be willing to spend, at least in developed economies, to offset those very hard-to-abate instances.”

      Sebregts noted that Shell is working on demonstrating DAC technologies in Houston, Texas, constructing what will become Europe’s largest hydrogen plant in the Netherlands, and taking other steps to profitably transition to a net-zero emissions energy company by 2050. “We need to understand what can help our customers transition quicker and how we can continue to satisfy their needs,” he said. “We must ensure that energy is affordable, accessible, and sustainable, as soon as possible.” More

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      in Energy

      Cobalt-free batteries could power cars of the future

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      Many electric vehicles are powered by batteries that contain cobalt — a metal that carries high financial, environmental, and social costs.

      MIT researchers have now designed a battery material that could offer a more sustainable way to power electric cars. The new lithium-ion battery includes a cathode based on organic materials, instead of cobalt or nickel (another metal often used in lithium-ion batteries).

      In a new study, the researchers showed that this material, which could be produced at much lower cost than cobalt-containing batteries, can conduct electricity at similar rates as cobalt batteries. The new battery also has comparable storage capacity and can be charged up faster than cobalt batteries, the researchers report.

      “I think this material could have a big impact because it works really well,” says Mircea Dincă, the W.M. Keck Professor of Energy at MIT. “It is already competitive with incumbent technologies, and it can save a lot of the cost and pain and environmental issues related to mining the metals that currently go into batteries.”

      Dincă is the senior author of the study, which appears today in the journal ACS Central Science. Tianyang Chen PhD ’23 and Harish Banda, a former MIT postdoc, are the lead authors of the paper. Other authors include Jiande Wang, an MIT postdoc; Julius Oppenheim, an MIT graduate student; and Alessandro Franceschi, a research fellow at the University of Bologna.

      Alternatives to cobalt

      Most electric cars are powered by lithium-ion batteries, a type of battery that is recharged when lithium ions flow from a positively charged electrode, called a cathode, to a negatively electrode, called an anode. In most lithium-ion batteries, the cathode contains cobalt, a metal that offers high stability and energy density.

      However, cobalt has significant downsides. A scarce metal, its price can fluctuate dramatically, and much of the world’s cobalt deposits are located in politically unstable countries. Cobalt extraction creates hazardous working conditions and generates toxic waste that contaminates land, air, and water surrounding the mines.

      “Cobalt batteries can store a lot of energy, and they have all of features that people care about in terms of performance, but they have the issue of not being widely available, and the cost fluctuates broadly with commodity prices. And, as you transition to a much higher proportion of electrified vehicles in the consumer market, it’s certainly going to get more expensive,” Dincă says.

      Because of the many drawbacks to cobalt, a great deal of research has gone into trying to develop alternative battery materials. One such material is lithium-iron-phosphate (LFP), which some car manufacturers are beginning to use in electric vehicles. Although still practically useful, LFP has only about half the energy density of cobalt and nickel batteries.

      Another appealing option are organic materials, but so far most of these materials have not been able to match the conductivity, storage capacity, and lifetime of cobalt-containing batteries. Because of their low conductivity, such materials typically need to be mixed with binders such as polymers, which help them maintain a conductive network. These binders, which make up at least 50 percent of the overall material, bring down the battery’s storage capacity.

      About six years ago, Dincă’s lab began working on a project, funded by Lamborghini, to develop an organic battery that could be used to power electric cars. While working on porous materials that were partly organic and partly inorganic, Dincă and his students realized that a fully organic material they had made appeared that it might be a strong conductor.

      This material consists of many layers of TAQ (bis-tetraaminobenzoquinone), an organic small molecule that contains three fused hexagonal rings. These layers can extend outward in every direction, forming a structure similar to graphite. Within the molecules are chemical groups called quinones, which are the electron reservoirs, and amines, which help the material to form strong hydrogen bonds.

      Those hydrogen bonds make the material highly stable and also very insoluble. That insolubility is important because it prevents the material from dissolving into the battery electrolyte, as some organic battery materials do, thereby extending its lifetime.

      “One of the main methods of degradation for organic materials is that they simply dissolve into the battery electrolyte and cross over to the other side of the battery, essentially creating a short circuit. If you make the material completely insoluble, that process doesn’t happen, so we can go to over 2,000 charge cycles with minimal degradation,” Dincă says.

      Strong performance

      Tests of this material showed that its conductivity and storage capacity were comparable to that of traditional cobalt-containing batteries. Also, batteries with a TAQ cathode can be charged and discharged faster than existing batteries, which could speed up the charging rate for electric vehicles.

      To stabilize the organic material and increase its ability to adhere to the battery’s current collector, which is made of copper or aluminum, the researchers added filler materials such as cellulose and rubber. These fillers make up less than one-tenth of the overall cathode composite, so they don’t significantly reduce the battery’s storage capacity.

      These fillers also extend the lifetime of the battery cathode by preventing it from cracking when lithium ions flow into the cathode as the battery charges.

      The primary materials needed to manufacture this type of cathode are a quinone precursor and an amine precursor, which are already commercially available and produced in large quantities as commodity chemicals. The researchers estimate that the material cost of assembling these organic batteries could be about one-third to one-half the cost of cobalt batteries.

      Lamborghini has licensed the patent on the technology. Dincă’s lab plans to continue developing alternative battery materials and is exploring possible replacement of lithium with sodium or magnesium, which are cheaper and more abundant than lithium. More

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      in Security

      A new way to swiftly eliminate micropollutants from water

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      “Zwitterionic” might not be a word you come across every day, but for Professor Patrick Doyle of the MIT Department of Chemical Engineering, it’s a word that’s central to the technology his group is developing to remove micropollutants from water. Derived from the German word “zwitter,” meaning “hybrid,” “zwitterionic” molecules are those with an equal number of positive and negative charges.

      Devashish Gokhale, a PhD student in Doyle’s lab, uses the example of a magnet to describe zwitterionic materials. “On a magnet, you have a north pole and a south pole that stick to each other, and on a zwitterionic molecule, you have a positive charge and a negative charge which stick to each other in a similar way.” Because many inorganic micropollutants and some organic micropollutants are themselves charged, Doyle and his team have been investigating how to deploy zwitterionic molecules to capture micropollutants in water. 

      In a new paper in Nature Water, Doyle, Gokhale, and undergraduate student Andre Hamelberg explain how they use zwitterionic hydrogels to sustainably capture both organic and inorganic micropollutants from water with minimal operational complexity. In the past, zwitterionic molecules have been used as coatings on membranes for water treatment because of their non-fouling properties. But in the Doyle group’s system, zwitterionic molecules are used to form the scaffold material, or backbone within the hydrogel — a porous three-dimensional network of polymer chains that contains a significant amount of water. “Zwitterionic molecules have very strong attraction to water compared to other materials which are used to make hydrogels or polymers,” says Gokhale. What’s more, the positive and negative charges on zwitterionic molecules cause the hydrogels to have lower compressibility than what has been commonly observed in hydrogels. This makes for significantly more swollen, robust, and porous hydrogels, which is important for the scale up of the hydrogel-based system for water treatment.

      The early stages of this research were supported by a seed grant from MIT’s Abdul Latif Jameel Water and Food Systems Lab (J-WAFS). Doyle’s group is now pursuing commercialization of the platform for both at-home use and industrial scale applications, with support from a J-WAFS Solutions grant.

      Seeking a sustainable solution

      Micropollutants are chemically diverse materials that can be harmful to human health and the environment, even though they are typically found at low concentrations (micrograms to milligrams per liter) relative to conventional contaminants. Micropollutants can be organic or inorganic and can be naturally-occurring or synthetic. Organic micropollutants are mostly carbon-based molecules and include pesticides and per- and polyfluoroalkyl substances (PFAS), known as “forever chemicals.” Inorganic micropollutants, such as heavy metals like lead and arsenic, tend to be smaller than organic micropollutants. Unfortunately, both organic and inorganic micropollutants are pervasive in the environment.

      Many micropollutants come from industrial processes, but the effects of human-induced climate change are also contributing to the environmental spread of micropollutants. Gokhale explains that, in California, for example, fires burn plastic electrical cables and leech micropollutants into natural ecosystems. Doyle adds that “outside of climate change, things like pandemics can spike the number of organic micropollutants in the environment due to high concentrations of pharmaceuticals in wastewater.”

      It’s no surprise then, that over the past few years micropollutants have become more and more of a concern. These chemicals have garnered attention in the media and led to “significant change in the environmental engineering and regulatory landscape” says Gokhale. In March 2023, the U.S. Environmental Protection Agency (EPA) proposed a strict, federal standard that would regulate six different PFAS chemicals in drinking water. Just last October, the EPA proposed banning the micropollutant trichloroethylene, a cancer-causing chemical that can be found in brake cleaners and other consumer products. And as recently as November, the EPA proposed that water utilities nationwide be required to replace all of their lead pipes to protect the public from lead exposure. Internationally, Gokhale notes the Oslo Paris Convention, whose mission is to protect the marine environment of the northeast Atlantic Ocean, including phasing out the discharge of offshore chemicals from the oil and gas industries. 

      With each new, necessary regulation to protect the safety of our water resources, the need for effective water treatment processes grows. Compounding this challenge is the need to make water treatment processes that are sustainable and energy-efficient. 

      The benchmark method to treat micropollutants in water is activated carbon. However, making filters with activated carbon is energy-intensive, requiring very high temperatures in large, centralized facilities. Gokhale says approximately “four kilograms of coal are needed to make one kilogram of activated carbon, so you lose a significant amount of carbon dioxide to the environment.” According to the World Economic Forum, global water and wastewater treatment accounts for 5 percent of annual emissions. In the U.S. alone, the EPA reports that drinking water and wastewater systems account for over 45 million tons of greenhouse gas emissions annually.

      “We need to develop methods which have smaller climate footprints than methods which are being used industrially today,” says Gokhale.

      Supporting a “high-risk” project

      In September 2019, Doyle and his lab embarked on an initial project to develop a microparticle-based platform to remove a broad range of micropollutants from water. Doyle’s group had been using hydrogels in pharmaceutical processing to formulate drug molecules into pill format. When he learned about the J-WAFS seed grant opportunity for early-stage research in water and food systems, Doyle realized his pharmaceutical work with hydrogels could be applied to environmental issues like water treatment. “I would never have gotten funding for this project if I went to the NSF [National Science Foundation], because they would just say, ‘you’re not a water person.’ But the J-WAFS seed grant offered a way for a high-risk, high-reward kind of project,” Doyle says.

      In March 2022, Doyle, Gokhale, and MIT undergraduate Ian Chen published findings from the seed grant work, describing their use of micelles within hydrogels for water treatment. Micelles are spherical structures that form when molecules called surfactants (found in things like soap), come in contact with water or other liquids. The team was able to synthesize micelle-laden hydrogel particles that soak up micropollutants from water like a sponge. Unlike activated carbon, the hydrogel particle system is made from environmentally friendly materials. Furthermore, the system’s materials are made at room temperature, making them exceedingly more sustainable than activated carbon.

      Building off the success of the seed grant, Doyle and his team were awarded a J-WAFS Solutions grant in September 2022 to help move their technology from the lab to the market. With this support, the researchers have been able to build, test, and refine pilot-scale prototypes of their hydrogel platform. System iterations during the solutions grant period have included the use of the zwitterionic molecules, a novel advancement from the seed grant work.  

      Rapid elimination of micropollutants is of special importance in commercial water treatment processes, where there is a limited amount of time water can spend inside the operational filtration unit. This is referred to as contact time, explains Gokhale. In municipal-scale or industrial-scale water treatment systems, contact times are usually less than 20 minutes and can be as short as five minutes. 

      “But as people have been trying to target these emerging micropollutants of concern, they realized they can’t get to sufficiently low concentrations on the same time scales as conventional contaminants,” Gokhale says. “Most technologies focus only on specific molecules or specific classes of molecules. So, you have whole technologies which are focusing only on PFAS, and then you have other technologies for lead and metals. When you start thinking about removing all of these contaminants from water, you end up with designs which have a very large number of unit operations. And that’s an issue because you have plants which are in the middle of large cities, and they don’t necessarily have space to expand to increase their contact times to efficiently remove multiple micropollutants,” he adds.

      Since zwitterionic molecules possess unique properties that confer high porosity, the researchers have been able to engineer a system for quicker uptake of micropollutants from water. Tests show that the hydrogels can eliminate six chemically diverse micropollutants at least 10 times faster than commercial activated carbon. The system is also compatible with a diverse set of materials, making it multifunctional. Micropollutants can bind to many different sites within the hydrogel platform: organic micropollutants bind to the micelles or surfactants while inorganic micropollutants bind to the zwitterionic molecules. Micelles, surfactants, zwitterionic molecules, and other chelating agents can be swapped in and out to essentially tune the system with different functionalities based on the profile of the water being treated. This kind of “plug-and-play” addition of various functional agents does not require a change in the design or synthesis of the hydrogel platform, and adding more functionalities does not take away from existing functionality. In this way, the zwitterionic-based system can rapidly remove multiple contaminants at lower concentrations in a single step, without the need for large, industrial units or capital expenditure. 

      Perhaps most importantly, the particles in the Doyle group’s system can be regenerated and used over and over again. By simply soaking the particles in an ethanol bath, they can be washed of micropollutants for indefinite use without loss of efficacy. When activated carbon is used for water treatment, the activated carbon itself becomes contaminated with micropollutants and must be treated as toxic chemical waste and disposed of in special landfills. Over time, micropollutants in landfills will reenter the ecosystem, perpetuating the problem.

      Arjav Shah, a PhD-MBA candidate in MIT’s Department of Chemical Engineering and the MIT Sloan School of Management, respectively, recently joined the team to lead commercialization efforts. The team has found that the zwitterionic hydrogels could be used in several real-world contexts, ranging from large-scale industrial packed beds to small-scale, portable, off-grid applications — for example, in tablets that could clean water in a canteen — and they have begun piloting the technology through a number of commercialization programs at MIT and in the greater Boston area.

      The combined strengths of each member of the team continue to drive the project forward in impactful ways, including undergraduate students like Andre Hamelberg, the third author on the Nature Water paper. Hamelberg is a participant in MIT’s Undergraduate Research Opportunities Program (UROP). Gokhale, who is also a J-WAFS Fellow, provides training and mentorship to Hamelberg and other UROP students in the lab.

      “We see this as an educational opportunity,” says Gokhale, noting that the UROP students learn science and chemical engineering through the research they conduct in the lab. The J-WAFS project has also been “a way of getting undergrads interested in water treatment and the more sustainable aspects of chemical engineering,” Gokhale says. He adds that it’s “one of the few projects which goes all the way from designing specific chemistries to building small filters and units and scaling them up and commercializing them. It’s a really good learning opportunity for the undergrads and we’re always excited to have them work with us.”

      In four years, the technology has been able to grow from an initial idea to a technology with scalable, real-world applications, making it an exemplar J-WAFS project. The fruitful collaboration between J-WAFS and the Doyle lab serves as inspiration for any MIT faculty who may want to apply their research to water or food systems projects.

      “The J-WAFS project serves as a way to demystify what a chemical engineer does,” says Doyle. “I think that there’s an old idea of chemical engineering as working in just oil and gas. But modern chemical engineering is focused on things which make life and the environment better.” More

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      Shell joins MIT.nano Consortium

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      MIT.nano has announced that Shell, a global group of energy and petrochemical companies, has joined the MIT.nano Consortium.

      “With an international perspective on the world’s energy challenges, Shell is an exciting addition to the MIT.nano Consortium,” says Vladimir Bulović, the founding faculty director of MIT.nano and the Fariborz Maseeh (1990) Professor of Emerging Technologies. “The quest to build a sustainable energy future will require creative thinking backed by broad and deep expertise that our Shell colleagues bring. They will be insightful collaborators for the MIT community and for our member companies as we work together to explore innovative technology strategies.”

      Founded in 1907 when Shell Transport and Trading Co. merged with Royal Dutch, Shell has more than a century’s worth of experience in the exploration, production, refining, and marketing of oil and natural gas and the manufacturing and marketing of chemicals. Operating in over 70 countries, Shell has set a target to become a net-zero emissions energy business by 2050. To achieve this, Shell is supporting developments of low-carbon energy solutions such as biofuels, hydrogen, charging for electric vehicles, and electricity generated by solar and wind power.

      “In line with our Powering Progress strategy, our research efforts to become a net-zero emission energy company by 2050 will require intense collaboration with academic leaders across a wide range of disciplines,” says Rolf van Benthem, Shell’s chief scientist for materials science. “We look forward to engaging with the top-notch PIs [principal investigators] at MIT.nano who excel in fields like materials design and nanoscale characterization for use in energy applications and carbon utilization. Together we can work on truly sustainable solutions for our society.”

      Shell has been engaged in research collaborations with MIT since 2002 and is a founding member of the MIT Energy Initiative (MITEI). Recent MIT projects supported by Shell include an urban building energy model with the MIT Sustainable Design Laboratory that explores energy-saving building retrofits, a study of the role and impact of hydrogen-based technology pathways with MITEI, and a materials science and engineering project to design better batteries for electric vehicles.

      The MIT.nano Consortium is a platform for academia-industry collaboration centered around research and innovation emerging from nanoscale science and engineering at MIT. Through activities that include quarterly industry consortium meetings, Shell will gain insight into the work of MIT.nano’s community of users and provide advice to help guide and advance nanoscale innovations at MIT alongside the 11 other consortium companies:

      Analog Devices;
      Draper;
      Edwards;
      Fujikura;
      IBM Research;
      Lam Research;
      NC;
      NEC;
      Raith;
      UpNano; and
      Viavi Solutions.
      MIT.nano continues to welcome new companies as sustaining members. For more details, visit the MIT.nano Consortium page. More

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      MIT researchers outline a path for scaling clean hydrogen production

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      Hydrogen is an integral component for the manufacture of steel, fertilizer, and a number of chemicals. Producing hydrogen using renewable electricity offers a way to clean up these and many other hard-to-decarbonize industries.

      But supporting the nascent clean hydrogen industry while ensuring it grows into a true force for decarbonization is complicated, in large part because of the challenges of sourcing clean electricity. To assist regulators and to clarify disagreements in the field, MIT researchers published a paper today in Nature Energy that outlines a path to scale the clean hydrogen industry while limiting emissions.

      Right now, U.S. electric grids are mainly powered by fossil fuels, so if scaling hydrogen production translates to greater electricity use, it could result in a major emissions increase. There is also the risk that “low-carbon” hydrogen projects could end up siphoning renewable energy that would have been built anyway for the grid. It is therefore critical to ensure that low-carbon hydrogen procures electricity from “additional” renewables, especially when hydrogen production is supported by public subsidies. The challenge is allowing hydrogen producers to procure renewable electricity in a cost-effective way that helps the industry grow, while minimizing the risk of high emissions.

      U.S. regulators have been tasked with sorting out this complexity. The Inflation Reduction Act (IRA) is offering generous production tax credits for low-carbon hydrogen. But the law didn’t specify exactly how hydrogen’s carbon footprint should be judged.

      To this end, the paper proposes a phased approach to qualify for the tax credits. In the first phase, hydrogen created from grid electricity can receive the credits under looser standards as the industry gets its footing. Once electricity demand for hydrogen production grows, the industry should be required to adhere to stricter standards for ensuring the electricity is coming from renewable sources. Finally, many years from now when the grid is mainly powered by renewable energy, the standards can loosen again.

      The researchers say the nuanced approach ensures the law supports the growth of clean hydrogen without coming at the expense of emissions.

      “If we can scale low-carbon hydrogen production, we can cut some significant sources of existing emissions and enable decarbonization of other critical industries,” says paper co-author Michael Giovanniello, a graduate student in MIT’s Technology and Policy Program. “At the same time, there’s a real risk of implementing the wrong requirements and wasting lots of money to subsidize carbon-intensive hydrogen production. So, you have to balance scaling the industry with reducing the risk of emissions. I hope there’s clarity and foresight in how this policy is implemented, and I hope our paper makes the argument clear for policymakers.”

      Giovanniello’s co-authors on the paper are MIT Energy Initiative (MITEI) Principal Research Scientist Dharik Mallapragada, MITEI Research Assistant Anna Cybulsky, and MIT Sloan School of Management Senior Lecturer Tim Schittekatte.

      On definitions and disagreements

      When renewable electricity from a wind farm or solar array flows through the grid, it’s mixed with electricity from fossil fuels. The situation raises a question worth billions of dollars in federal tax credits: What are the carbon dioxide emissions of grid users who are also signing agreements to procure electricity from renewables?

      One way to answer this question is via energy system models that can simulate various scenarios related to technology configurations and qualifying requirements for receiving the credit.

      To date, many studies using such models have come up with very different emissions estimates for electrolytic hydrogen production. One source of disagreement is over “time matching,” which refers to how strictly to align the timing of electric hydrogen production with the generation of clean electricity. One proposed approach, known as hourly time matching, would require that electricity consumption to produce hydrogen is accounted for by procured clean electricity at every hour.

      A less stringent approach, called annual time matching, would offer more flexibility in hourly electricity consumption for hydrogen production, so long as the annual consumption matches the annual generation from the procured clean electricity generation. The added flexibility could reduce the cost of hydrogen production, which is critical for scaling its use, but could lead to greater emissions per unit of hydrogen produced.

      Another point of disagreement stems from how hydrogen producers purchase renewable electricity. If an electricity user procures energy from an existing solar farm, it’s simply increasing overall electricity demand and taking clean energy away from other users. But if the tax credits only go to electric hydrogen producers that sign power purchase agreements with new renewable suppliers, they’re supporting clean electricity that wouldn’t have otherwise been contributing to the grid. This concept is known as “additionality.”

      The researchers analyzed previous studies that reached conflicting conclusions, and identified different interpretations of additionality underlying their methodologies. One interpretation of additionality is that new electrolytic hydrogen projects do not compete with nonhydrogen demand for renewable energy resources. The other assumes that they do compete for all newly deployed renewables — and, because of low-carbon hydrogen subsidies, the electrolyzers take priority.

      Using DOLPHYN, an open-source energy systems model, the researchers tested how these two interpretations of additionality (the “compete” and “noncompete” scenarios) impact the cost and emissions of the alternative time-matching requirements (hourly and annual) associated with grid-interconnected hydrogen production. They modeled two regional U.S. grids — in Texas and Florida — which represent the high and low end of renewables deployment. They further tested the interaction of four critical policy factors with the hydrogen tax credits, including renewable portfolio standards, constraints of renewables and energy storage deployment, limits on hydrogen electrolyzer capacity factors, and competition with natural gas-based hydrogen with carbon capture.

      They show that the different modeling interpretations of additionality are the primary factor explaining the vastly different estimates of emissions from electrolyzer hydrogen under annual time-matching.

      Getting policy right

      The paper concludes that the right way to implement the production tax credit qualifying requirements depends on whether you believe we live in a “compete” or “noncompete” world. But reality is not so binary.

      “What framework is more appropriate is going to change with time as we deploy more hydrogen and the grid decarbonizes, so therefore the policy has to be adaptive to those changes,” Mallapragada says. “It’s an evolving story that’s tied to what’s happening in the rest of the energy system, and in particular the electric grid, both from the technological as policy perspective.”

      Today, renewables deployment is driven, in part, by binding factors, such as state renewable portfolio standards and corporate clean-energy commitments, as well as by purely market forces. Since the electrolyzer is so nascent, and today resembles a “noncompete” world, the researchers argue for starting with the less strict annual requirement. But as hydrogen demand for renewable electricity grows, and market competition drives an increasing quantity of renewables deployment, transitioning to hourly matching will be necessary to avoid high emissions.

      This phased approach necessitates deliberate, long-term planning from regulators. “If regulators make a decision and don’t outline when they’ll reassess that decision, they might never reassess that decision, so we might get locked into a bad policy,” Giovanniello explains. In particular, the paper highlights the risk of locking in an annual time-matching requirement that leads to significant emissions in future.

      The researchers hope their findings will contribute to upcoming policy decisions around the Inflation Reduction Act’s tax credits. They started looking into this question around a year ago, making it a quick turnaround by academic standards.

      “There was definitely a sense to be timely in our analysis so as to be responsive to the needs of policy,” Mallapragada says.

      The researchers say the paper can also help policymakers understand the emissions impacts of companies procuring renewable energy credits to meet net-zero targets and electricity suppliers attempting to sell “green” electricity.

      “This question is relevant in a lot of different domains,” Schittekatte says. “Other popular examples are the emission impacts of data centers that procure green power, or even the emission impacts of your own electric car sourcing power from your rooftop solar and the grid. There are obviously differences based on the technology in question, but the underlying research question we’ve answered is the same. This is an extremely important topic for the energy transition.” More

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      AI meets climate: MIT Energy and Climate Hack 2023

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      The MIT Energy and Climate Hack brought together participants from myriad fields and disciplines to develop rapid, innovative solutions to one of the most complex challenges facing society today: the global energy and climate crisis. Hundreds of students from MIT and colleges across the globe convened on MIT’s campus and virtually for this year’s event, which was held Nov. 10-12.

      Established in 2013, the MIT Energy and Climate Hack has been the launchpad for innovative and sustainable solutions for a decade; an annual reminder that exciting new ideas are always just around the corner.

      According to Claire Lorenzo, an MIT student organizer and communications director for this year’s Energy and Climate Hack, “There were a lot of people from a lot of places who showed up; both virtually and in person. It was encouraging to see how driven everyone was. How passionate they were about finding great solutions. You could see these ideas starting to form immediately.”

      On the first day, representatives from companies across numerous industries presented participants with their most pressing energy and climate-related challenges. Once the gathering broke into teams, participants had two days to “hack the challenge” they were assigned and present their solution to company representatives, fellow hackers, and judges.  

      The focus areas at this year’s event were energy markets, transportation, and farms and forests. Participating corporate sponsors included Google, Crusoe, Ironwood, Foothill Ventures, Koidra, Mitra Chem, Avangrid, Schneider Electric, First Solar, and Climate Ledger. 

      This year’s event also marked the first time that artificial intelligence emerged as a viable tool for developing creative climate solutions. Lorenzo observed, “I’m studying computer science, so exploring how AI could be harnessed to have a positive impact on the climate was particularly exciting for me. It can be applicable to virtually any domain. Like transportation, [with emissions] for example. In agriculture, too.”

      Energy and Climate Hack organizers identified the implementation of four core AI applications for special consideration: the acceleration of discovery (shortening the development process while simultaneously producing less waste), optimizing real-world solutions (utilizing automation to increase efficiency), prediction (using AI to improve prediction algorithms), and processing unstructured data (using AI to analyze and scale large amounts of data efficiently).

      “If there was a shared sentiment among the participants, it would probably be the idea that there isn’t a singular solution to climate change,” says Lorenzo, “and that requires cooperation from various industries, leveraging knowledge and experience from numerous fields, to make a lasting impact.”

      After the initial round of presentations concluded, one team from each challenge advanced from the preliminary presentation judging session to the final presentation round, where they pitched their solutions to a crowded room of attendees. Once the semi-finalists had pitched their solutions, the judges deliberated over the entries and selected team Fenergy, which worked in the energy markets sector, as the winners. The team, consisting of Alessandro Fumi, Amal Nammouchi, Amaury De Bock, Cyrine Chaabani, and Robbie Lee V, said, “Our solution, Unbiased Cathode, enables researchers to assess the supply chain implications of battery materials before development begins, hence reducing the lab-to-production timeline.”

      “They created a LLM [large language model]-powered tool that allows innovative new battery technologies to be iterated and developed much more efficiently,” Lorenzo added.

      When asked what she will remember most about her first experience at the MIT Energy and Climate Hack, Lorenzo replied, “Having hope for the future. Hope from seeing the passion that so many people have to find a solution. Hope from seeing all of these individuals come so far to tackle this challenge and make a difference. If we continue to develop and implement solutions like these on a global level, I am hopeful.”

      Students interested in learning more about the MIT Energy and Climate Hackathon, or participating in next year’s Hack, can find more information on the event website. More