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    New program bolsters innovation in next-generation artificial intelligence hardware

    The MIT AI Hardware Program is a new academia and industry collaboration aimed at defining and developing translational technologies in hardware and software for the AI and quantum age. A collaboration between the MIT School of Engineering and MIT Schwarzman College of Computing, involving the Microsystems Technologies Laboratories and programs and units in the college, the cross-disciplinary effort aims to innovate technologies that will deliver enhanced energy efficiency systems for cloud and edge computing.

    “A sharp focus on AI hardware manufacturing, research, and design is critical to meet the demands of the world’s evolving devices, architectures, and systems,” says Anantha Chandrakasan, dean of the MIT School of Engineering and Vannevar Bush Professor of Electrical Engineering and Computer Science. “Knowledge-sharing between industry and academia is imperative to the future of high-performance computing.”

    Based on use-inspired research involving materials, devices, circuits, algorithms, and software, the MIT AI Hardware Program convenes researchers from MIT and industry to facilitate the transition of fundamental knowledge to real-world technological solutions. The program spans materials and devices, as well as architecture and algorithms enabling energy-efficient and sustainable high-performance computing.

    “As AI systems become more sophisticated, new solutions are sorely needed to enable more advanced applications and deliver greater performance,” says Daniel Huttenlocher, dean of the MIT Schwarzman College of Computing and Henry Ellis Warren Professor of Electrical Engineering and Computer Science. “Our aim is to devise real-world technological solutions and lead the development of technologies for AI in hardware and software.”

    The inaugural members of the program are companies from a wide range of industries including chip-making, semiconductor manufacturing equipment, AI and computing services, and information systems R&D organizations. The companies represent a diverse ecosystem, both nationally and internationally, and will work with MIT faculty and students to help shape a vibrant future for our planet through cutting-edge AI hardware research.

    The five inaugural members of the MIT AI Hardware Program are:  

    Amazon, a global technology company whose hardware inventions include the Kindle, Amazon Echo, Fire TV, and Astro; 
    Analog Devices, a global leader in the design and manufacturing of analog, mixed signal, and DSP integrated circuits; 
    ASML, an innovation leader in the semiconductor industry, providing chipmakers with hardware, software, and services to mass produce patterns on silicon through lithography; 
    NTT Research, a subsidiary of NTT that conducts fundamental research to upgrade reality in game-changing ways that improve lives and brighten our global future; and 
    TSMC, the world’s leading dedicated semiconductor foundry.

    The MIT AI Hardware Program will create a roadmap of transformative AI hardware technologies. Leveraging MIT.nano, the most advanced university nanofabrication facility anywhere, the program will foster a unique environment for AI hardware research.  

    “We are all in awe at the seemingly superhuman capabilities of today’s AI systems. But this comes at a rapidly increasing and unsustainable energy cost,” says Jesús del Alamo, the Donner Professor in MIT’s Department of Electrical Engineering and Computer Science. “Continued progress in AI will require new and vastly more energy-efficient systems. This, in turn, will demand innovations across the entire abstraction stack, from materials and devices to systems and software. The program is in a unique position to contribute to this quest.”

    The program will prioritize the following topics:

    analog neural networks;
    new roadmap CMOS designs;
    heterogeneous integration for AI systems;
    onolithic-3D AI systems;
    analog nonvolatile memory devices;
    software-hardware co-design;
    intelligence at the edge;
    intelligent sensors;
    energy-efficient AI;
    intelligent internet of things (IIoT);
    neuromorphic computing;
    AI edge security;
    quantum AI;
    wireless technologies;
    hybrid-cloud computing; and
    high-performance computation.

    “We live in an era where paradigm-shifting discoveries in hardware, systems communications, and computing have become mandatory to find sustainable solutions — solutions that we are proud to give to the world and generations to come,” says Aude Oliva, senior research scientist in the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) and director of strategic industry engagement in the MIT Schwarzman College of Computing.

    The new program is co-led by Jesús del Alamo and Aude Oliva, and Anantha Chandrakasan serves as chair. More

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    Q&A: Climate Grand Challenges finalists on new pathways to decarbonizing industry

    Note: This is the third article in a four-part interview series highlighting the work of the 27 MIT Climate Grand Challenges finalist teams, which received a total of $2.7 million in startup funding to advance their projects. In April, the Institute will name a subset of the finalists as multiyear flagship projects.

    The industrial sector is the backbone of today’s global economy, yet its activities are among the most energy-intensive and the toughest to decarbonize. Efforts to reach net-zero targets and avert runaway climate change will not succeed without new solutions for replacing sources of carbon emissions with low-carbon alternatives and developing scalable nonemitting applications of hydrocarbons.

    In conversations prepared for MIT News, faculty from three of the teams with projects in the competition’s “Decarbonizing complex industries and processes” category discuss strategies for achieving impact in hard-to-abate sectors, from long-distance transportation and building construction to textile manufacturing and chemical refining. The other Climate Grand Challenges research themes include using data and science to forecast climate-related risk, building equity and fairness into climate solutions, and removing, managing, and storing greenhouse gases. The following responses have been edited for length and clarity.

    Moving toward an all-carbon material approach to building

    Faced with the prospect of building stock doubling globally by 2050, there is a great need for sustainable alternatives to conventional mineral- and metal-based construction materials. Mark Goulthorpe, associate professor in the Department of Architecture, explains the methods behind Carbon >Building, an initiative to develop energy-efficient building materials by reorienting hydrocarbons from current use as fuels to environmentally benign products, creating an entirely new genre of lightweight, all-carbon buildings that could actually drive decarbonization.

    Q: What are all-carbon buildings and how can they help mitigate climate change?

    A: Instead of burning hydrocarbons as fuel, which releases carbon dioxide and other greenhouse gases that contribute to atmospheric pollution, we seek to pioneer a process that uses carbon materially to build at macro scale. New forms of carbon — carbon nanotube, carbon foam, etc. — offer salient properties for building that might effectively displace the current material paradigm. Only hydrocarbons offer sufficient scale to beat out the billion-ton mineral and metal markets, and their perilous impact. Carbon nanotube from methane pyrolysis is of special interest, as it offers hydrogen as a byproduct.

    Q: How will society benefit from the widespread use of all-carbon buildings?

    A: We anticipate reducing costs and timelines in carbon composite buildings, while increasing quality, longevity, and performance, and diminishing environmental impact. Affordability of buildings is a growing problem in all global markets as the cost of labor and logistics in multimaterial assemblies creates a burden that is very detrimental to economic growth and results in overcrowding and urban blight.

    Alleviating these challenges would have huge societal benefits, especially for those in lower income brackets who cannot afford housing, but the biggest benefit would be in drastically reducing the environmental footprint of typical buildings, which account for nearly 40 percent of global energy consumption.

    An all-carbon building sector will not only reduce hydrocarbon extraction, but can produce higher value materials for building. We are looking to rethink the building industry by greatly streamlining global production and learning from the low-labor methods pioneered by composite manufacturing such as wind turbine blades, which are quick and cheap to produce. This technology can improve the sustainability and affordability of buildings — and holds the promise of faster, cheaper, greener, and more resilient modes of dwelling.

    Emissions reduction through innovation in the textile industry

    Collectively, the textile industry is responsible for over 4 billion metric tons of carbon dioxide equivalent per year, or 5 to 10 percent of global greenhouse gas emissions — more than aviation and maritime shipping combined. And the problem is only getting worse with the industry’s rapid growth. Under the current trajectory, consumption is projected to increase 30 percent by 2030, reaching 102 million tons. A diverse group of faculty and researchers led by Gregory Rutledge, the Lammot du Pont Professor in the Department of Chemical Engineering, and Yuly Fuentes-Medel, project manager for fiber technologies and research advisor to the MIT Innovation Initiative, is developing groundbreaking innovations to reshape how textiles are selected, sourced, designed, manufactured, and used, and to create the structural changes required for sustained reductions in emissions by this industry.

    Q: Why has the textile industry been difficult to decarbonize?

    A: The industry currently operates under a linear model that relies heavily on virgin feedstock, at roughly 97 percent, yet recycles or downcycles less than 15 percent. Furthermore, recent trends in “fast fashion” have led to massive underutilization of apparel, such that products are discarded on average after only seven to 10 uses. In an industry with high volume and low margins, replacement technologies must achieve emissions reduction at scale while maintaining performance and economic efficiency.

    There are also technical barriers to adopting circular business models, from the challenge of dealing with products comprising fiber blends and chemical additives to the low maturity of recycling technologies. The environmental impacts of textiles and apparel have been estimated using life cycle analysis, and industry-standard indexes are under development to assess sustainability throughout the life cycle of a product, but information and tools are needed to model how new solutions will alter those impacts and include the consumer as an active player to keep our planet safe. This project seeks to deliver both the new solutions and the tools to evaluate their potential for impact.

    Q: Describe the five components of your program. What is the anticipated timeline for implementing these solutions?

    A: Our plan comprises five programmatic sections, which include (1) enabling a paradigm shift to sustainable materials using nontraditional, carbon-negative polymers derived from biomass and additives that facilitate recycling; (2) rethinking manufacturing with processes to structure fibers and fabrics for performance, waste reduction, and increased material efficiency; (3) designing textiles for value by developing products that are customized, adaptable, and multifunctional, and that interact with their environment to reduce energy consumption; (4) exploring consumer behavior change through human interventions that reduce emissions by encouraging the adoption of new technologies, increased utilization of products, and circularity; and (5) establishing carbon transparency with systems-level analyses that measure the impact of these strategies and guide decision making.

    We have proposed a five-year timeline with annual targets for each project. Conservatively, we estimate our program could reduce greenhouse gas emissions in the industry by 25 percent by 2030, with further significant reductions to follow.

    Tough-to-decarbonize transportation

    Airplanes, transoceanic ships, and freight trucks are critical to transporting people and delivering goods, and the cornerstone of global commerce, manufacturing, and tourism. But these vehicles also emit 3.7 billion tons of carbon dioxide annually and, left unchecked, they could take up a quarter of the remaining carbon budget by 2050. William Green, the Hoyt C. Hottel Professor in the Department Chemical Engineering, co-leads a multidisciplinary team with Steven Barrett, professor of aeronautics and astronautics and director of the MIT Laboratory for Aviation and the Environment, that is working to identify and advance economically viable technologies and policies for decarbonizing heavy duty trucking, shipping, and aviation. The Tough to Decarbonize Transportation research program aims to design and optimize fuel chemistry and production, vehicles, operations, and policies to chart the course to net-zero emissions by midcentury.

    Q: What are the highest priority focus areas of your research program?

    A: Hydrocarbon fuels made from biomass are the least expensive option, but it seems impractical, and probably damaging to the environment, to harvest the huge amount of biomass that would be needed to meet the massive and growing energy demands from these sectors using today’s biomass-to-fuel technology. We are exploring strategies to increase the amount of useful fuel made per ton of biomass harvested, other methods to make low-climate-impact hydrocarbon fuels, such as from carbon dioxide, and ways to make fuels that do not contain carbon at all, such as with hydrogen, ammonia, and other hydrogen carriers.

    These latter zero-carbon options free us from the need for biomass or to capture gigatons of carbon dioxide, so they could be a very good long-term solution, but they would require changing the vehicles significantly, and the construction of new refueling infrastructure, with high capital costs.

    Q: What are the scientific, technological, and regulatory barriers to scaling and implementing potential solutions?

    A: Reimagining an aviation, trucking, and shipping sector that connects the world and increases equity without creating more environmental damage is challenging because these vehicles must operate disconnected from the electrical grid and have energy requirements that cannot be met by batteries alone. Some of the concepts do not even exist in prototype yet, and none of the appealing options have been implemented at anywhere near the scale required.

    In most cases, we do not know the best way to make the fuel, and for new fuels the vehicles and refueling systems all need to be developed. Also, new fuels, or large-scale use of biomass, will introduce new environmental problems that need to be carefully considered, to ensure that decarbonization solutions do not introduce big new problems.

    Perhaps most difficult are the policy, economic, and equity issues. A new long-haul transportation system will be expensive, and everyone will be affected by the increased cost of shipping freight. To have the desired climate impact, the transport system must change in almost every country. During the transition period, we will need both the existing vehicle and fuel system to keep running smoothly, even as a new low-greenhouse system is introduced. We will also examine what policies could make that work and how we can get countries around the world to agree to implement them. More

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    A better way to separate gases

    Industrial processes for chemical separations, including natural gas purification and the production of oxygen and nitrogen for medical or industrial uses, are collectively responsible for about 15 percent of the world’s energy use. They also contribute a corresponding amount to the world’s greenhouse gas emissions. Now, researchers at MIT and Stanford University have developed a new kind of membrane for carrying out these separation processes with roughly 1/10 the energy use and emissions.

    Using membranes for separation of chemicals is known to be much more efficient than processes such as distillation or absorption, but there has always been a tradeoff between permeability — how fast gases can penetrate through the material — and selectivity — the ability to let the desired molecules pass through while blocking all others. The new family of membrane materials, based on “hydrocarbon ladder” polymers, overcomes that tradeoff, providing both high permeability and extremely good selectivity, the researchers say.

    The findings are reported today in the journal Science, in a paper by Yan Xia, an associate professor of chemistry at Stanford; Zachary Smith, an assistant professor of chemical engineering at MIT; Ingo Pinnau, a professor at King Abdullah University of Science and Technology, and five others.

    Gas separation is an important and widespread industrial process whose uses include removing impurities and undesired compounds from natural gas or biogas, separating oxygen and nitrogen from air for medical and industrial purposes, separating carbon dioxide from other gases for carbon capture, and producing hydrogen for use as a carbon-free transportation fuel. The new ladder polymer membranes show promise for drastically improving the performance of such separation processes. For example, separating carbon dioxide from methane, these new membranes have five times the selectivity and 100 times the permeability of existing cellulosic membranes for that purpose. Similarly, they are 100 times more permeable and three times as selective for separating hydrogen gas from methane.

    The new type of polymers, developed over the last several years by the Xia lab, are referred to as ladder polymers because they are formed from double strands connected by rung-like bonds, and these linkages provide a high degree of rigidity and stability to the polymer material. These ladder polymers are synthesized via an efficient and selective chemistry the Xia lab developed called CANAL, an acronym for catalytic arene-norbornene annulation, which stitches readily available chemicals into ladder structures with hundreds or even thousands of rungs. The polymers are synthesized in a solution, where they form rigid and kinked ribbon-like strands that can easily be made into a thin sheet with sub-nanometer-scale pores by using industrially available polymer casting processes. The sizes of the resulting pores can be tuned through the choice of the specific hydrocarbon starting compounds. “This chemistry and choice of chemical building blocks allowed us to make very rigid ladder polymers with different configurations,” Xia says.

    To apply the CANAL polymers as selective membranes, the collaboration made use of Xia’s expertise in polymers and Smith’s specialization in membrane research. Holden Lai, a former Stanford doctoral student, carried out much of the development and exploration of how their structures impact gas permeation properties. “It took us eight years from developing the new chemistry to finding the right polymer structures that bestow the high separation performance,” Xia says.

    The Xia lab spent the past several years varying the structures of CANAL polymers to understand how their structures affect their separation performance. Surprisingly, they found that adding additional kinks to their original CANAL polymers significantly improved the mechanical robustness of their membranes and boosted their selectivity  for molecules of similar sizes, such as oxygen and nitrogen gases, without losing permeability of the more permeable gas. The selectivity actually improves as the material ages. The combination of high selectivity and high permeability makes these materials outperform all other polymer materials in many gas separations, the researchers say.

    Today, 15 percent of global energy use goes into chemical separations, and these separation processes are “often based on century-old technologies,” Smith says. “They work well, but they have an enormous carbon footprint and consume massive amounts of energy. The key challenge today is trying to replace these nonsustainable processes.” Most of these processes require high temperatures for boiling and reboiling solutions, and these often are the hardest processes to electrify, he adds.

    For the separation of oxygen and nitrogen from air, the two molecules only differ in size by about 0.18 angstroms (ten-billionths of a meter), he says. To make a filter capable of separating them efficiently “is incredibly difficult to do without decreasing throughput.” But the new ladder polymers, when manufactured into membranes produce tiny pores that achieve high selectivity, he says. In some cases, 10 oxygen molecules permeate for every nitrogen, despite the razor-thin sieve needed to access this type of size selectivity. These new membrane materials have “the highest combination of permeability and selectivity of all known polymeric materials for many applications,” Smith says.

    “Because CANAL polymers are strong and ductile, and because they are soluble in certain solvents, they could be scaled for industrial deployment within a few years,” he adds. An MIT spinoff company called Osmoses, led by authors of this study, recently won the MIT $100K entrepreneurship competition and has been partly funded by The Engine to commercialize the technology.

    There are a variety of potential applications for these materials in the chemical processing industry, Smith says, including the separation of carbon dioxide from other gas mixtures as a form of emissions reduction. Another possibility is the purification of biogas fuel made from agricultural waste products in order to provide carbon-free transportation fuel. Hydrogen separation for producing a fuel or a chemical feedstock, could also be carried out efficiently, helping with the transition to a hydrogen-based economy.

    The close-knit team of researchers is continuing to refine the process to facilitate the development from laboratory to industrial scale, and to better understand the details on how the macromolecular structures and packing result in the ultrahigh selectivity. Smith says he expects this platform technology to play a role in multiple decarbonization pathways, starting with hydrogen separation and carbon capture, because there is such a pressing need for these technologies in order to transition to a carbon-free economy.

    “These are impressive new structures that have outstanding gas separation performance,” says Ryan Lively, am associate professor of chemical and biomolecular engineering at Georgia Tech, who was not involved in this work. “Importantly, this performance is improved during membrane aging and when the membranes are challenged with concentrated gas mixtures. … If they can scale these materials and fabricate membrane modules, there is significant potential practical impact.”

    The research team also included Jun Myun Ahn and Ashley Robinson at Stanford, Francesco Benedetti at MIT, now the chief executive officer at Osmoses, and Yingge Wang at King Abdullah University of Science and Technology in Saudi Arabia. The work was supported by the Stanford Natural Gas Initiative, the Sloan Research Fellowship, the U.S. Department of Energy Office of Basic Energy Sciences, and the National Science Foundation. More

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    Finding her way to fusion

    “I catch myself startling people in public.”

    Zoe Fisher’s animated hands carry part of the conversation as she describes how her naturally loud and expressive laughter turned heads in the streets of Yerevan. There during MIT’s Independent Activities period (IAP), she was helping teach nuclear science at the American University of Armenia, before returning to MIT to pursue fusion research at the Plasma Science and Fusion Center (PSFC).

    Startling people may simply be in Fisher’s DNA. She admits that when she first arrived at MIT, knowing nothing about nuclear science and engineering (NSE), she chose to join that department’s Freshman Pre-Orientation Program (FPOP) “for the shock value.” It was a choice unexpected by family, friends, and mostly herself. Now in her senior year, a 2021 recipient of NSE’s Irving Kaplan Award for academic achievements by a junior and entering a fifth-year master of science program in nuclear fusion, Fisher credits that original spontaneous impulse for introducing her to a subject she found so compelling that, after exploring multiple possibilities, she had to return to it.

    Fisher’s venture to Armenia, under the guidance of NSE associate professor Areg Danagoulian, is not the only time she has taught oversees with MISTI’s Global Teaching Labs, though it is the first time she has taught nuclear science, not to mention thermodynamics and materials science. During IAP 2020 she was a student teacher at a German high school, teaching life sciences, mathematics, and even English to grades five through 12. And after her first year she explored the transportation industry with a mechanical engineering internship in Tuscany, Italy.

    By the time she was ready to declare her NSE major she had sampled the alternatives both overseas and at home, taking advantage of MIT’s Undergraduate Research Opportunities Program (UROP). Drawn to fusion’s potential as an endless source of carbon-free energy on earth, she decided to try research at the PSFC, to see if the study was a good fit. 

    Much fusion research at MIT has favored heating hydrogen fuel inside a donut-shaped device called a tokamak, creating plasma that is hot and dense enough for fusion to occur. Because plasma will follow magnetic field lines, these devices are wrapped with magnets to keep the hot fuel from damaging the chamber walls.

    Fisher was assigned to SPARC, the PSFC’s new tokamak collaboration with MIT startup Commonwealth Fusion Systems (CSF), which uses a game-changing high-temperature superconducting (HTS) tape to create fusion magnets that minimize tokamak size and maximize performance. Working on a database reference book for SPARC materials, she was finding purpose even in the most repetitive tasks. “Which is how I knew I wanted to stay in fusion,” she laughs.

    Fisher’s latest UROP assignment takes her — literally — deeper into SPARC research. She works in a basement laboratory in building NW13 nicknamed “The Vault,” on a proton accelerator whose name conjures an underworld: DANTE. Supervised by PSFC Director Dennis Whyte and postdoc David Fischer, she is exploring the effects of radiation damage on the thin HTS tape that is key to SPARC’s design, and ultimately to the success of ARC, a prototype working fusion power plant.

    Because repetitive bombardment with neutrons produced during the fusion process can diminish the superconducting properties of the HTS, it is crucial to test the tape repeatedly. Fisher assists in assembling and testing the experimental setups for irradiating the HTS samples. Fisher recalls her first project was installing a “shutter” that would allow researchers to control exactly how much radiation reached the tape without having to turn off the entire experiment.

    “You could just push the button — block the radiation — then unblock it. It sounds super simple, but it took many trials. Because first I needed the right size solenoid, and then I couldn’t find a piece of metal that was small enough, and then we needed cryogenic glue…. To this day the actual final piece is made partially of paper towels.”

    She shrugs and laughs. “It worked, and it was the cheapest option.”

    Fisher is always ready to find the fun in fusion. Referring to DANTE as “A really cool dude,” she admits, “He’s perhaps a bit fickle. I may or may not have broken him once.” During a recent IAP seminar, she joined other PSFC UROP students to discuss her research, and expanded on how a mishap can become a gateway to understanding.

    “The grad student I work with and I got to repair almost the entire internal circuit when we blew the fuse — which originally was a really bad thing. But it ended up being great because we figured out exactly how it works.”

    Fisher’s upbeat spirit makes her ideal not only for the challenges of fusion research, but for serving the MIT community. As a student representative for NSE’s Diversity, Equity and Inclusion Committee, she meets monthly with the goal of growing and supporting diversity within the department.

    “This opportunity is impactful because I get my voice, and the voices of my peers, taken seriously,” she says. “Currently, we are spending most of our efforts trying to identify and eliminate hurdles based on race, ethnicity, gender, and income that prevent people from pursuing — and applying to — NSE.”

    To break from the lab and committees, she explores the Charles River as part of MIT’s varsity sailing team, refusing to miss a sunset. She also volunteers as an FPOP mentor, seeking to provide incoming first-years with the kind of experience that will make them want to return to the topic, as she did.

    She looks forward to continuing her studies on the HTS tapes she has been irradiating, proposing to send a current pulse above the critical current through the tape, to possibly anneal any defects from radiation, which would make repairs on future fusion power plants much easier.

    Fisher credits her current path to her UROP mentors and their infectious enthusiasm for the carbon-free potential of fusion energy.

    “UROPing around the PSFC showed me what I wanted to do with my life,” she says. “Who doesn’t want to save the world?” More

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    Q&A: Latifah Hamzah ’12 on creating sustainable solutions in Malaysia and beyond

    Latifah Hamzah ’12 graduated from MIT with a BS in mechanical engineering and minors in energy studies and music. During their time at MIT, Latifah participated in various student organizations, including the MIT Symphony Orchestra, Alpha Phi Omega, and the MIT Design/Build/Fly team. They also participated in the MIT Energy Initiative’s Undergraduate Research Opportunities Program (UROP) in the lab of former professor of mechanical engineering Alexander Mitsos, examining solar-powered thermal and electrical co-generation systems.

    After graduating from MIT, Latifah worked as a subsea engineer at Shell Global Solutions and co-founded Engineers Without Borders – Malaysia, a nonprofit organization dedicated to finding sustainable and empowering solutions that impact disadvantaged populations in Malaysia. More recently, Latifah received a master of science in mechanical engineering from Stanford University, where they are currently pursuing a PhD in environmental engineering with a focus on water and sanitation in developing contexts.

    Q: What inspired you to pursue energy studies as an undergraduate student at MIT?

    A: I grew up in Malaysia, where I was at once aware of both the extent to which the oil and gas industry is a cornerstone of the economy and the need to transition to a lower-carbon future. The Energy Studies minor was therefore enticing because it gave me a broader view of the energy space, including technical, policy, economic, and other viewpoints. This was my first exposure to how things worked in the real world — in that many different fields and perspectives had to be considered cohesively in order to have a successful, positive, and sustained impact. Although the minor was predominantly grounded in classroom learning, what I learned drove me to want to discover for myself how the forces of technology, society, and policy interacted in the field in my subsequent endeavors.

    In addition to the breadth that the minor added to my education, it also provided a structure and focus for me to build on my technical fundamentals. This included taking graduate-level classes and participating in UROPs that had specific energy foci. These were my first forays into questions that, while still predominantly technical, were more open-ended and with as-yet-unknown answers that would be substantially shaped by the framing of the question. This shift in mindset required from typical undergraduate classes and problem sets took a bit of adjusting to, but ultimately gave me the confidence and belief that I could succeed in a more challenging environment.

    Q: How did these experiences with energy help shape your path forward, particularly in regard to your work with Engineers Without Borders – Malaysia and now at Stanford?

    A: When I returned home after graduation, I was keen to harness my engineering education and explore in practice what the Energy Studies minor curriculum had taught by theory and case studies: to consider context, nuance, and interdisciplinary and myriad perspectives to craft successful, sustainable solutions. Recognizing that there were many underserved communities in Malaysia, I co-founded Engineers Without Borders – Malaysia with some friends with the aim of working with these communities to bring simple and sustainable engineering solutions. Many of these projects did have an energy focus. For example, we designed, sized, and installed micro-hydro or solar-power systems for various indigenous communities, allowing them to continue living on their ancestral lands while reducing energy poverty. Many other projects incorporated other aspects of engineering, such as hydrotherapy pools for folks with special needs, and water and sanitation systems for stateless maritime communities.

    Through my work with Engineers Without Borders – Malaysia, I found a passion for the broader aspects of sustainability, development, and equity. By spending time with communities in the field and sharing in their experiences, I recognized gaps in my skill set that I could work on to be more effective in advocating for social and environmental justice. In particular, I wanted to better understand communities and their perspectives while being mindful of my positionality. In addition, I wanted to address the more systemic aspects of the problems they faced, which I felt in many cases would only be possible through a combination of research, evidence, and policy. To this end, I embarked on a PhD in environmental engineering with a minor in anthropology and pursued a Community-Based Research Fellowship with Stanford’s Haas Center for Public Service. I have also participated in the Rising Environmental Leaders Program (RELP), which helps graduate students “hone their leadership and communications skills to maximize the impact of their research.” RELP afforded me the opportunity to interact with representatives from government, NGOs [nongovernmental organizations], think tanks, and industry, from which I gained a better understanding of the policy and adjacent ecosystems at both the federal and state levels.

    Q: What are you currently studying, and how does it relate to your past work and educational experiences?

    A: My dissertation investigates waste management and monitoring for improved planetary health in three distinct projects. Suboptimal waste management can lead to poor outcomes, including environmental contamination, overuse of resources, and lost economic and environmental opportunities in resource recovery. My first project showed that three combinations of factors resulted in ruminant feces contaminating the stored drinking water supplies of households in rural Kenya, and the results were published in the International Journal of Environmental Research and Public Health. Consequently, water and sanitation interventions must also consider animal waste for communities to have safe drinking water.

    My second project seeks to establish a circular economy in the chocolate industry with indigenous Malaysian farmers and the Chocolate Concierge, a tree-to-bar social enterprise. Having designed and optimized apparatuses and processes to create biochar from cacao husk waste, we are now examining its impact on the growth of cacao saplings and their root systems. The hope is that biochar will increase the resilience of saplings for when they are transplanted from the nursery to the farm. As biochar can improve soil health and yield while reducing fertilizer inputs and sequestering carbon, farmers can accrue substantial economic and environmental benefits, especially if they produce, use, and sell it themselves.

    My third project investigates the gap in sanitation coverage worldwide and potential ways of reducing it. Globally, 46 percent of the population lacks access to safely managed sanitation, while the majority of the 54 percent who do have access use on-site sanitation facilities such as septic tanks and latrines. Given that on-site, decentralized systems typically have a lower space and resource footprint, are cheaper to build and maintain, and can be designed to suit various contexts, they could represent the best chance of reaching the sanitation Sustainable Development Goal. To this end, I am part of a team of researchers at the Criddle Group at Stanford working to develop a household-scale system as part of the Gates Reinvent the Toilet Challenge, an initiative aimed at developing new sanitation and toilet technologies for developing contexts.

    The thread connecting these projects is a commitment to investigating both the technical and socio-anthropological dimensions of an issue to develop sustainable, reliable, and environmentally sensitive solutions, especially in low- and middle-income countries (LMICs). I believe that an interdisciplinary approach can provide a better understanding of the problem space, which will hopefully lead to effective potential solutions that can have a greater community impact.

    Q: What do you plan to do once you obtain your PhD?

    A: I hope to continue working in the spheres of water and sanitation and/or sustainability post-PhD. It is a fascinating moment to be in this space as a person of color from an LMIC, especially as ideas such as community-based research and decolonizing fields and institutions are becoming more widespread and acknowledged. Even during my time at Stanford, I have noticed some shifts in the discourse, although we still have a long way to go to achieve substantive and lasting change. Folks like me are underrepresented in forums where the priorities, policies, and financing of aid and development are discussed at the international or global scale. I hope I’ll be able to use my qualifications, experience, and background to advocate for more just outcomes.

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

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    Q&A: Climate Grand Challenges finalists on accelerating reductions in global greenhouse gas emissions

    This is the second article in a four-part interview series highlighting the work of the 27 MIT Climate Grand Challenges finalists, which received a total of $2.7 million in startup funding to advance their projects. In April, the Institute will name a subset of the finalists as multiyear flagship projects.

    Last month, the Intergovernmental Panel on Climate Change (IPCC), an expert body of the United Nations representing 195 governments, released its latest scientific report on the growing threats posed by climate change, and called for drastic reductions in greenhouse gas emissions to avert the most catastrophic outcomes for humanity and natural ecosystems.

    Bringing the global economy to net-zero carbon dioxide emissions by midcentury is complex and demands new ideas and novel approaches. The first-ever MIT Climate Grand Challenges competition focuses on four problem areas including removing greenhouse gases from the atmosphere and identifying effective, economic solutions for managing and storing these gases. The other Climate Grand Challenges research themes address using data and science to forecast climate-related risk, decarbonizing complex industries and processes, and building equity and fairness into climate solutions.

    In the following conversations prepared for MIT News, faculty from three of the teams working to solve “Removing, managing, and storing greenhouse gases” explain how they are drawing upon geological, biological, chemical, and oceanic processes to develop game-changing techniques for carbon removal, management, and storage. Their responses have been edited for length and clarity.

    Directed evolution of biological carbon fixation

    Agricultural demand is estimated to increase by 50 percent in the coming decades, while climate change is simultaneously projected to drastically reduce crop yield and predictability, requiring a dramatic acceleration of land clearing. Without immediate intervention, this will have dire impacts on wild habitat, rob the livelihoods of hundreds of millions of subsistence farmers, and create hundreds of gigatons of new emissions. Matthew Shoulders, associate professor in the Department of Chemistry, talks about the working group he is leading in partnership with Ed Boyden, the Y. Eva Tan professor of neurotechnology and Howard Hughes Medical Institute investigator at the McGovern Institute for Brain Research, that aims to massively reduce carbon emissions from agriculture by relieving core biochemical bottlenecks in the photosynthetic process using the most sophisticated synthetic biology available to science.

    Q: Describe the two pathways you have identified for improving agricultural productivity and climate resiliency.

    A: First, cyanobacteria grow millions of times faster than plants and dozens of times faster than microalgae. Engineering these cyanobacteria as a source of key food products using synthetic biology will enable food production using less land, in a fundamentally more climate-resilient manner. Second, carbon fixation, or the process by which carbon dioxide is incorporated into organic compounds, is the rate-limiting step of photosynthesis and becomes even less efficient under rising temperatures. Enhancements to Rubisco, the enzyme mediating this central process, will both improve crop yields and provide climate resilience to crops needed by 2050. Our team, led by Robbie Wilson and Max Schubert, has created new directed evolution methods tailored for both strategies, and we have already uncovered promising early results. Applying directed evolution to photosynthesis, carbon fixation, and food production has the potential to usher in a second green revolution.

    Q: What partners will you need to accelerate the development of your solutions?

    A: We have already partnered with leading agriculture institutes with deep experience in plant transformation and field trial capacity, enabling the integration of our improved carbon-dioxide-fixing enzymes into a wide range of crop plants. At the deployment stage, we will be positioned to partner with multiple industry groups to achieve improved agriculture at scale. Partnerships with major seed companies around the world will be key to leverage distribution channels in manufacturing supply chains and networks of farmers, agronomists, and licensed retailers. Support from local governments will also be critical where subsidies for seeds are necessary for farmers to earn a living, such as smallholder and subsistence farming communities. Additionally, our research provides an accessible platform that is capable of enabling and enhancing carbon dioxide sequestration in diverse organisms, extending our sphere of partnership to a wide range of companies interested in industrial microbial applications, including algal and cyanobacterial, and in carbon capture and storage.

    Strategies to reduce atmospheric methane

    One of the most potent greenhouse gases, methane is emitted by a range of human activities and natural processes that include agriculture and waste management, fossil fuel production, and changing land use practices — with no single dominant source. Together with a diverse group of faculty and researchers from the schools of Humanities, Arts, and Social Sciences; Architecture and Planning; Engineering; and Science; plus the MIT Schwarzman College of Computing, Desiree Plata, associate professor in the Department of Civil and Environmental Engineering, is spearheading the MIT Methane Network, an integrated approach to formulating scalable new technologies, business models, and policy solutions for driving down levels of atmospheric methane.

    Q: What is the problem you are trying to solve and why is it a “grand challenge”?

    A: Removing methane from the atmosphere, or stopping it from getting there in the first place, could change the rates of global warming in our lifetimes, saving as much as half a degree of warming by 2050. Methane sources are distributed in space and time and tend to be very dilute, making the removal of methane a challenge that pushes the boundaries of contemporary science and engineering capabilities. Because the primary sources of atmospheric methane are linked to our economy and culture — from clearing wetlands for cultivation to natural gas extraction and dairy and meat production — the social and economic implications of a fundamentally changed methane management system are far-reaching. Nevertheless, these problems are tractable and could significantly reduce the effects of climate change in the near term.

    Q: What is known about the rapid rise in atmospheric methane and what questions remain unanswered?

    A: Tracking atmospheric methane is a challenge in and of itself, but it has become clear that emissions are large, accelerated by human activity, and cause damage right away. While some progress has been made in satellite-based measurements of methane emissions, there is a need to translate that data into actionable solutions. Several key questions remain around improving sensor accuracy and sensor network design to optimize placement, improve response time, and stop leaks with autonomous controls on the ground. Additional questions involve deploying low-level methane oxidation systems and novel catalytic materials at coal mines, dairy barns, and other enriched sources; evaluating the policy strategies and the socioeconomic impacts of new technologies with an eye toward decarbonization pathways; and scaling technology with viable business models that stimulate the economy while reducing greenhouse gas emissions.

    Deploying versatile carbon capture technologies and storage at scale

    There is growing consensus that simply capturing current carbon dioxide emissions is no longer sufficient — it is equally important to target distributed sources such as the oceans and air where carbon dioxide has accumulated from past emissions. Betar Gallant, the American Bureau of Shipping Career Development Associate Professor of Mechanical Engineering, discusses her work with Bradford Hager, the Cecil and Ida Green Professor of Earth Sciences in the Department of Earth, Atmospheric and Planetary Sciences, and T. Alan Hatton, the Ralph Landau Professor of Chemical Engineering and director of the School of Chemical Engineering Practice, to dramatically advance the portfolio of technologies available for carbon capture and permanent storage at scale. (A team led by Assistant Professor Matěj Peč of EAPS is also addressing carbon capture and storage.)

    Q: Carbon capture and storage processes have been around for several decades. What advances are you seeking to make through this project?

    A: Today’s capture paradigms are costly, inefficient, and complex. We seek to address this challenge by developing a new generation of capture technologies that operate using renewable energy inputs, are sufficiently versatile to accommodate emerging industrial demands, are adaptive and responsive to varied societal needs, and can be readily deployed to a wider landscape.

    New approaches will require the redesign of the entire capture process, necessitating basic science and engineering efforts that are broadly interdisciplinary in nature. At the same time, incumbent technologies have been optimized largely for integration with coal- or natural gas-burning power plants. Future applications must shift away from legacy emitters in the power sector towards hard-to-mitigate sectors such as cement, iron and steel, chemical, and hydrogen production. It will become equally important to develop and optimize systems targeted for much lower concentrations of carbon dioxide, such as in oceans or air. Our effort will expand basic science studies as well as human impacts of storage, including how public engagement and education can alter attitudes toward greater acceptance of carbon dioxide geologic storage.

    Q: What are the expected impacts of your proposed solution, both positive and negative?

    A: Renewable energy cannot be deployed rapidly enough everywhere, nor can it supplant all emissions sources, nor can it account for past emissions. Carbon capture and storage (CCS) provides a demonstrated method to address emissions that will undoubtedly occur before the transition to low-carbon energy is completed. CCS can succeed even if other strategies fail. It also allows for developing nations, which may need to adopt renewables over longer timescales, to see equitable economic development while avoiding the most harmful climate impacts. And, CCS enables the future viability of many core industries and transportation modes, many of which do not have clear alternatives before 2050, let alone 2040 or 2030.

    The perceived risks of potential leakage and earthquakes associated with geologic storage can be minimized by choosing suitable geologic formations for storage. Despite CCS providing a well-understood pathway for removing enough of the carbon dioxide already emitted into the atmosphere, some environmentalists vigorously oppose it, fearing that CCS rewards oil companies and disincentivizes the transition away from fossil fuels. We believe that it is more important to keep in mind the necessity of meeting key climate targets for the sake of the planet, and welcome those who can help. More

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    Building communities, founding a startup with people in mind

    MIT postdoc Francesco Benedetti admits he wasn’t always a star student. But the people he met along his educational journey inspired him to strive, which led him to conduct research at MIT, launch a startup, and even lead the team that won the 2021 MIT $100K Entrepreneurship Competition. Now he is determined to make sure his company, Osmoses, succeeds in boosting the energy efficiency of traditional and renewable natural gas processing, hydrogen production, and carbon capture — thus helping to address climate change.

    “I can’t be grateful enough to MIT for bringing together a community of people who want to change the world,” Benedetti says. “Now we have a technology that can solve one of the big problems of our society.”

    Benedetti and his team have developed an innovative way to separate molecules using a membrane fine enough to extract impurities such as carbon dioxide or hydrogen sulfide from raw natural gas to obtain higher-quality fuel, fulfilling a crucial need in the energy industry. “Natural gas now provides about 40 percent of the energy used to power homes and industry in the United States,” Benedetti says. Using his team’s technology to upgrade natural gas more efficiently could reduce emissions of greenhouse gases while saving enough energy to power the equivalent of 7 million additional U.S. homes for a year, he adds.

    The MIT community

    Benedetti first came to MIT in 2017 as a visiting student from the University of Bologna in Italy, where he was working on membranes for gas separation for his PhD in chemical engineering. Having completed a master’s thesis on water desalination at the University of Texas (UT) at Austin, he connected with UT alumnus Zachary P. Smith, the Robert N. Noyce Career Development Professor of Chemical Engineering at MIT, and the two discovered they shared a vision. “We found ourselves very much aligned on the need for new technology in industry to lower the energy consumption of separating components,” Benedetti says.

    Although Benedetti had always been interested in making a positive impact on the world, particularly the environment, he says it was his university studies that first sparked his interest in more efficient separation technologies. “When you study chemical engineering, you understand hundreds of ways the field can have a positive impact in the world. But we learn very early that 15 percent of the world’s energy is wasted because of inefficient chemical separation — because we still rely on centuries-old technology,” he says. Most separation processes still use heat or toxic solvents to separate components, he explains.

    Still, Benedetti says, his main drive comes from the joy of working with terrific mentors and colleagues. “It’s the people I’ve met that really inspired me to tackle the biggest challenges and find that intrinsic motivation,” he says.

    To help build his community at MIT and provide support for international students, Benedetti co-founded the MIT Visiting Student Association (VISTA) in September 2017. By February 2018, the organization had hundreds of members and official Institute recognition. In May 2018, the group won two Institute awards, including the Golden Beaver Award for enhancing the campus environment. “VISTA gave me a sense of belonging; I loved it,” Benedetti says.

    Membrane technology

    Benedetti also published two papers on membrane research during his stint as a visiting student at MIT, so he was delighted to return in 2019 for postdoctoral work through the MIT Energy Initiative, where he was a 2019-20 ExxonMobil-MIT Energy Fellow. “I came back because the research was extremely exciting, but also because I got extremely passionate about the energy I found on campus and with the people,” he says.

    Returning to MIT enabled Benedetti to continue his work with Smith and Holden Lai, both of whom helped co-found Osmoses. Lai, a recent Stanford PhD in chemistry who was also a visiting student at MIT in 2018, is now the chief technology officer at Osmoses. Co-founder Katherine Mizrahi Rodriguez ’17, an MIT PhD candidate, joined the team more recently.

    Together, the Osmoses team has developed polymer membranes with microporosities capable of filtering gases by separating out molecules that differ by as little as a fraction of an angstrom — a unit of length equal to one hundred-millionth of a centimeter. “We can get up to five times higher selectivity than commercially available technology for methane upgrading, and this has been observed operating the membranes in industrially relevant environments,” Benedetti says.

    Today, methane upgrading — removing carbon dioxide (CO2) from raw natural gas to obtain a higher-grade fuel — is often accomplished using amine absorption, a process that uses toxic solvents to capture CO2 and burns methane to fuel the regeneration of those solvents for reuse. Using Osmoses’ filters would eliminate the need for such solvents while reducing CO2 emissions by up to 16 million metric tons per year in the United States alone, Benedetti says.

    The technology has a wide range of applications — in oxygen and nitrogen generation, hydrogen purification, and carbon capture, for example — but Osmoses plans to start with the $5 billion market for natural gas upgrading because the need to bring innovation and sustainability to that space is urgent, says Benedetti, who received guidance in bringing technology to market from MIT’s Deshpande Center for Technological Innovation. The Osmoses team has also received support from the MIT Sandbox Innovation Fund Program.

    The next step for the startup is to build an industrial-scale prototype, and Benedetti says the company got a huge boost toward that goal in May when it won the MIT $100K Entrepreneurship Competition, a student-run contest that has launched more than 160 companies since it began in 1990. Ninety teams began the competition by pitching their startup ideas; 20 received mentorship and development funding; then eight finalists presented business plans to compete for the $100,000 prize. “Because of this, we’re getting a lot of interest from venture capital firms, investors, companies, corporate funds, et cetera, that want to partner with us or to use our product,” he says. In June, the Osmoses team received a two-year Activate Fellowship, which will support moving its research to market; in October, it won the Northeast Regional and Carbon Sequestration Prizes at the Cleantech Open Accelerator; and in November, the team closed a $3 million pre-seed round of financing.

    FAIL!

    Naturally, Benedetti hopes Osmoses is on the path to success, but he wants everyone to know that there is no shame in failures that come from best efforts. He admits it took him three years longer than usual to finish his undergraduate and master’s degrees, and he says, “I have experienced the pressure you feel when society judges you like a book by its cover and how much a lack of inspired leaders and a supportive environment can kill creativity and the will to try.”

    That’s why in 2018 he, along with other MIT students and VISTA members, started FAIL!–Inspiring Resilience, an organization that provides a platform for sharing unfiltered stories and the lessons leaders have gleaned from failure. “We wanted to help de-stigmatize failure, appreciate vulnerabilities, and inspire humble leadership, eventually creating better communities,” Benedetti says. “If we can make failures, big and small, less intimidating and all-consuming, individuals with great potential will be more willing to take risks, think outside the box, and try things that may push new boundaries. In this way, more breakthrough discoveries are likely to follow, without compromising anyone’s mental health.”

    Benedetti says he will strive to create a supportive culture at Osmoses, because people are central to success. “What drives me every day is the people. I would have no story without the people around me,” he says. “The moment you lose touch with people, you lose the opportunity to create something special.”

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

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    How to clean solar panels without water

    Solar power is expected to reach 10 percent of global power generation by the year 2030, and much of that is likely to be located in desert areas, where sunlight is abundant. But the accumulation of dust on solar panels or mirrors is already a significant issue — it can reduce the output of photovoltaic panels by as much as 30 percent in just one month — so regular cleaning is essential for such installations.

    But cleaning solar panels currently is estimated to use about 10 billion gallons of water per year — enough to supply drinking water for up to 2 million people. Attempts at waterless cleaning are labor intensive and tend to cause irreversible scratching of the surfaces, which also reduces efficiency. Now, a team of researchers at MIT has devised a way of automatically cleaning solar panels, or the mirrors of solar thermal plants, in a waterless, no-contact system that could significantly reduce the dust problem, they say.

    The new system uses electrostatic repulsion to cause dust particles to detach and virtually leap off the panel’s surface, without the need for water or brushes. To activate the system, a simple electrode passes just above the solar panel’s surface, imparting an electrical charge to the dust particles, which are then repelled by a charge applied to the panel itself. The system can be operated automatically using a simple electric motor and guide rails along the side of the panel. The research is described today in the journal Science Advances, in a paper by MIT graduate student Sreedath Panat and professor of mechanical engineering Kripa Varanasi.

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    Despite concerted efforts worldwide to develop ever more efficient solar panels, Varanasi says, “a mundane problem like dust can actually put a serious dent in the whole thing.” Lab tests conducted by Panat and Varanasi showed that the dropoff of energy output from the panels happens steeply at the very beginning of the process of dust accumulation and can easily reach 30 percent reduction after just one month without cleaning. Even a 1 percent reduction in power, for a 150-megawatt solar installation, they calculated, could result in a $200,000 loss in annual revenue. The researchers say that globally, a 3 to 4 percent reduction in power output from solar plants would amount to a loss of between $3.3 billion and $5.5 billion.

    “There is so much work going on in solar materials,” Varanasi says. “They’re pushing the boundaries, trying to gain a few percent here and there in improving the efficiency, and here you have something that can obliterate all of that right away.”

    Many of the largest solar power installations in the world, including ones in China, India, the U.A.E., and the U.S., are located in desert regions. The water used for cleaning these solar panels using pressurized water jets has to be trucked in from a distance, and it has to be very pure to avoid leaving behind deposits on the surfaces. Dry scrubbing is sometimes used but is less effective at cleaning the surfaces and can cause permanent scratching that also reduces light transmission.

    Water cleaning makes up about 10 percent of the operating costs of solar installations. The new system could potentially reduce these costs while improving the overall power output by allowing for more frequent automated cleanings, the researchers say.

    “The water footprint of the solar industry is mind boggling,” Varanasi says, and it will be increasing as these installations continue to expand worldwide. “So, the industry has to be very careful and thoughtful about how to make this a sustainable solution.”

    Other groups have tried to develop electrostatic based solutions, but these have relied on a layer called an electrodynamic screen, using interdigitated electrodes. These screens can have defects that allow moisture in and cause them to fail, Varanasi says. While they might be useful on a place like Mars, he says, where moisture is not an issue, even in desert environments on Earth this can be a serious problem.

    The new system they developed only requires an electrode, which can be a simple metal bar, to pass over the panel, producing an electric field that imparts a charge to the dust particles as it goes. An opposite charge applied to a transparent conductive layer just a few nanometers thick deposited on the glass covering of the the solar panel then repels the particles, and by calculating the right voltage to apply, the researchers were able to find a voltage range sufficient to overcome the pull of gravity and adhesion forces, and cause the dust to lift away.

    Using specially prepared laboratory samples of dust with a range of particle sizes, experiments proved that the process works effectively on a laboratory-scale test installation, Panat says. The tests showed that humidity in the air provided a thin coating of water on the particles, which turned out to be crucial to making the effect work. “We performed experiments at varying humidities from 5 percent to 95 percent,” Panat says. “As long as the ambient humidity is greater than 30 percent, you can remove almost all of the particles from the surface, but as humidity decreases, it becomes harder.”

    Varanasi says that “the good news is that when you get to 30 percent humidity, most deserts actually fall in this regime.” And even those that are typically drier than that tend to have higher humidity in the early morning hours, leading to dew formation, so the cleaning could be timed accordingly.

    “Moreover, unlike some of the prior work on electrodynamic screens, which actually do not work at high or even moderate humidity, our system can work at humidity even as high as 95 percent, indefinitely,” Panat says.

    In practice, at scale, each solar panel could be fitted with railings on each side, with an electrode spanning across the panel. A small electric motor, perhaps using a tiny portion of the output from the panel itself, would drive a belt system to move the electrode from one end of the panel to the other, causing all the dust to fall away. The whole process could be automated or controlled remotely. Alternatively, thin strips of conductive transparent material could be permanently arranged above the panel, eliminating the need for moving parts.

    By eliminating the dependency on trucked-in water, by eliminating the buildup of dust that can contain corrosive compounds, and by lowering the overall operational costs, such systems have the potential to significantly improve the overall efficiency and reliability of solar installations, Varanasi says.

    The research was supported by Italian energy firm Eni. S.p.A. through the MIT Energy Initiative. More