The winners of this year’s MADMEC competition identified a class of materials that could offer a more efficient way to keep greenhouses cool.

After Covid-19 put the materials science competition on pause for two years, on Tuesday SmartClime, a team made up of three MIT graduate students, took home the first place, $10,000 prize.

The team showed that a type of material that changes color in response to an electric voltage could reduce energy usage and save money if coated onto the panes of glass in greenhouses.

“This project came out of our love of gardening,” said SmartClime team member and PhD candidate Isabella Caruso in the winning presentation. “Greenhouses let you grow things year-round, even in New England, but even greenhouse pros need to use heating furnaces in the winter and ventilation in the summer. All of that can be very labor- and energy-intensive.”

Current options to keep greenhouses cool include traditional air conditioning units, venting and fans, and simple cloth. To develop a better solution, the team looked through scientific papers to find materials with the right climate control properties.

Two classes of materials that looked promising were thermochromic coatings, which change color based on temperature, and electrochromic solutions, which change color based on electric voltage.

Creating both the thermochromic and electrochromic solutions required the team to assemble nanoparticles and spin-coat them onto glass substrates. In lab tests, the electrochromic material performed well, turning a deep bluish hue to reduce the heat coming into the greenhouse while also letting in enough light for plants. Specifically, the electrochromic cell kept its test box about 1 to 3 degrees Celsius cooler than the test box coated in regular glass.

The team estimated that greenhouse owners could make back the added costs of the electrochromic paneling through savings on other climate-control measures. Additional benefits of using the material include reducing heat-related crop losses, increasing crop yields, and reducing water requirements.

Hosted by MIT’s Department of Materials Science and Engineering (DMSE), the competition was the culmination of team projects that began last spring and included a series of design challenges throughout the summer. Each team received guidance, access to equipment and labs, and up to $1,000 in funding to build and test their prototypes.

“It’s great to be back and to have everyone here in person,” Mike Tarkanian, a senior lecturer in DMSE and coordinator of MADMEC, said at the event. “I’ve enjoyed getting back to normal, doing the design challenges over the summer and celebrating with everyone here today.”

The second-place prize was split between YarnZ, which identified a nanofiber yarn that is more sustainable than traditional textile fibers, and WasteAway, which has developed a waste bin monitoring device that can identify the types of items thrown into trash and recycling bins and flag misplaced items.

YarnZ (which stands for Yarns Are Really NanofiberZ), developed a nanofiber yarn that is more degradable than traditional microfiber yarns without sacrificing on performance.

A large chunk of the waste and emissions in the clothing industry come from polyester, a slow-degrading polymer that requires an energy-intensive melt spinning process before it’s spun into the fibers of our clothes.

“The biggest thing I want to impress upon you today is that the textile industry is a major greenhouse gas-producing entity and also produces a huge amount of waste,” YarnZ member and PhD candidate Natalie Mamrol said in the presentation.

To replace polyester, the team developed a continuous process in which a type of nanofiber film collects in a water bath before being twisted into yarn. In subsequent tests, the nanofiber-based yarn degraded more quicky than traditional microfibers and showed comparable durability. YarnZ believes this early data should encourage others to explore nanofibers as a viable replacement in the clothing industry and to invest in scaling the approach for industrial settings.

WasteAway’s system includes a camera that sits on top of trash bins and uses artificial intelligence to recognize items that people throw away.

Of the 300 million tons of waste generated in the U.S. each year, more than half ends up in landfills. A lot of that waste could have been composted or recycled but was misplaced during disposal.

“When someone throws something into the bin, our sensor detects the motion and captures an image,” explains WasteAway’s Melissa Stok, an undergraduate at MIT. “Those images are then processed by our machine-learning algorithm to find contamination.”

Each device costs less than $30, and the team says that cost could go down as parts are bought at larger scales. The insights gleaned from the device could help waste management officials identify contaminated trash piles as well as inform education efforts by revealing common mistakes people make.

Overall, Tarkanian believes the competition was a success not only because of the final results, but because of the experience the students got throughout the MADMEC program, which included several smaller, hands-on competitions involving laser cutters, 3-D printers, soldering irons, and other equipment many students said they had never used before.

“They end up getting into the lab through these design challenges, which have them compete in various engineering tasks,” Tarkanian says. “It helps them get comfortable designing and prototyping, and they often end up using those tools in their research later.” More

One glance at the news lately will reveal countless headlines on the dire state of global water and food security. Pollution, supply chain disruptions, and the war in Ukraine are all threatening water and food systems, compounding climate change impacts from heat waves, drought, floods, and wildfires.

Every year, MIT’s Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) offers fellowships to outstanding MIT graduate students who are working on innovative ways to secure water and food supplies in light of these urgent worldwide threats. J-WAFS announced this year’s fellowship recipients last April. Aditya Ghodgaonkar and Devashish Gokhale were awarded Rasikbhai L. Meswani Fellowships for Water Solutions, which are made possible by a generous gift from Elina and Nikhil Meswani and family. James Zhang, Katharina Fransen, and Linzixuan (Rhoda) Zhang were awarded J-WAFS Fellowships for Water and Food Solutions. The J-WAFS Fellowship for Water and Food Solutions is funded in part by J-WAFS Research Affiliate companies: Xylem, Inc., a water technology company, and GoAigua, a company leading the digital transformation of the water industry.

The five fellows were each awarded a stipend and full tuition for one semester. They also benefit from mentorship, networking connections, and opportunities to showcase their research.

“This year’s cohort of J-WAFS fellows show an indefatigable drive to explore, create, and push back boundaries,” says John H. Lienhard, director of J-WAFS. “Their passion and determination to create positive change for humanity are evident in these unique video portraits, which describe their solutions-oriented research in water and food,” Lienhard adds.

J-WAFS funder Community Jameel recently commissioned video portraitures of each student that highlight their work and their inspiration to solve challenges in water and food. More about each J-WAFS fellow and their research follows.

Play video

Katharina Fransen

In Professor Bradley Olsen’s lab in the Department of Chemical Engineering, Katharina Fransen works to develop biologically-based, biodegradable plastics which can be used for food packing that won’t pollute the environment. Fransen, a third-year PhD student, is motivated by the challenge of protecting the most vulnerable global communities from waste generated by the materials that are essential to connecting them to the global food supply. “We can’t ensure that all of our plastic waste gets recycled or reused, and so we want to make sure that if it does escape into the environment it can degrade, and that’s kind of where a lot of my research really comes in,” says Fransen. Most of her work involves creating polymers, or “really long chains of chemicals,” kind of like the paper rings a lot of us looped into chains as kids, Fransen explains. The polymers are optimized for food packaging applications to keep food fresher for longer, preventing food waste. Fransen says she finds the work “really interesting from the scientific perspective as well as from the idea that [she’s] going to make the world a little better with these new materials.” She adds, “I think it is both really fulfilling and really exciting and engaging.”

Play video

Aditya Ghodgaonkar

“When I went to Kenya this past spring break, I had an opportunity to meet a lot of farmers and talk to them about what kind of maintenance issues they face,” says Aditya Ghodgaonkar, PhD candidate in the Department of Mechanical Engineering. Ghodgaonkar works with Associate Professor Amos Winter in the Global Engineering and Research (GEAR) Lab, where he designs hydraulic components for drip irrigation systems to make them water-efficient, off-grid, inexpensive, and low-maintenance. On his trip to Kenya, Ghodgaonkar gained firsthand knowledge from farmers about a common problem they encounter: clogging of drip irrigation emitters. He learned that clogging can be an expensive technical challenge to diagnose, mitigate, and resolve. He decided to focus his attention on designing emitters that are resistant to clogging, testing with sand and passive hydrodynamic filtration back in the lab at MIT. “I got into this from an academic standpoint,” says Ghodgaonkar. “It is only once I started working on the emitters, spoke with industrial partners that make these emitters, spoke with farmers, that I really truly appreciated the impact of what we’re doing.”

Play video

Devashish Gokhale

Devashish Gokhale is a PhD student advised by Professor Patrick Doyle in the Department of Chemical Engineering. Gokhale’s commitment to global water security stems from his childhood in Pune, India, where both flooding and drought can occur depending on the time of year. “I’ve had these experiences where there’s been too much water and also too little water” he recalls. At MIT, Gokhale is developing cost-effective, sustainable, and reusable materials for water treatment with a focus on the elimination of emerging contaminants and low-concentration pollutants like heavy metals. Specifically, he works on making and optimizing polymeric hydrogel microparticles that can absorb micropollutants. “I know how important it is to do something which is not just scientifically interesting, but something which is impactful in a real way,” says Gokhale. Before starting a research project he asks himself, “are people going to be able to afford this? Is it really going to reach the people who need it the most?” Adding these constraints in the beginning of the research process sometimes makes the problem more difficult to solve, but Gokhale notes that in the end, the solution is much more promising.

Play video

James Zhang

“We don’t really think much about it, it’s transparent, odorless, we just turn on our sink in many parts of the world and it just flows through,” says James Zhang when talking about water. Yet he notes that “many other parts of the world face water scarcity and this will only get worse due to global climate change.” A PhD student in the Department of Mechanical Engineering, Zhang works in the Nano Engineering Laboratory with Professor Gang Chen. Zhang is working on a technology that uses light-induced evaporation to clean water. He is currently investigating the fundamental properties of how light at different wavelengths interacts with liquids at the surface, particularly with brackish water surfaces. With strong theoretical and experimental components, his research could lead to innovations in desalinating water at high energy efficiencies. Zhang hopes that the technology can one day “produce lots of clean water for communities around the world that currently don’t have access to fresh water,” and create a new appreciation for this common liquid that many of us might not think about on a day-to-day basis.

Play video

Linzixuan (Rhoda) Zhang

“Around the world there are about 2 billion people currently suffering from micronutrient deficiency because they do not have access to very healthy, very fresh food,” says chemical engineering PhD candidate Linzixuan (Rhoda) Zhang. This fact led Zhang to develop a micronutrient delivery platform that fortifies foods with essential vitamins and nutrients. With her advisors, Professor Robert Langer and Research Scientist Ana Jaklenec, Zhang brings biomedical engineering approaches to global health issues. Zhang says that “one of the most serious problems is vitamin A deficiency, because vitamin A is not very stable.” She goes on to explain that although vitamin A is present in different vegetables, when the vegetables are cooked, vitamin A can easily degrade. Zhang helped develop a group of biodegradable polymers that can stabilize micronutrients under cooking and storage conditions. With this technology, vitamin A, for example, could be encapsulated and effectively stabilized under boiling water. The platform has also shown efficient release in a simulation of the stomach environment. Zhang says it is the “little, tiny steps every day that are pushing us forward to the final impactful product.” More

Australia is facing a serious lighting waste challenge, however lighting recycling is on the rise as people realise how easy and convenient it is. Millions of old light bulbs, tubes and lamps are thrown into landfills around the country every year even though it’s bad for the environment. The best way to tackle our growing […] More

As plastic pollution continues to mount, with growing risks to ecosystems and wildlife, manufacturers are beginning to make ambitious commitments to keep new plastics out of the environment. A growing number have signed onto the U.S. Plastics Pact, which pledges to make 100 percent of plastic packaging reusable, recyclable, or compostable, and to see 50 percent of it effectively recycled or composted, by 2025.

But for companies that make large numbers of small, disposable plastics, these pocket-sized objects are a major barrier to realizing their recycling goals.

“Think about items like your toothbrush, your travel-size toothpaste tubes, your travel-size shampoo bottles,” says Alexis Hocken, a second-year PhD student in the MIT Department of Chemical Engineering. “They end up actually slipping through the cracks of current recycling infrastructure. So you might put them in your recycling bin at home, they might make it all the way to the sorting facility, but when it comes down to actually sorting them, they never make it into a recycled plastic bale at the very end of the line.”

Now, a group of five consumer products companies is working with MIT to develop a sorting process that can keep their smallest plastic products inside the recycling chain. The companies — Colgate-Palmolive, Procter & Gamble, the Estée Lauder Companies, L’Oreal, and Haleon — all manufacture a large volume of “small format” plastics, or products less than two inches long in at least two dimensions. In a collaboration with Brad Olsen, the Alexander and I. Michael Kasser (1960) Professor of Chemical Engineering; Desiree Plata, an associate professor of civil and environmental engineering; the MIT Environmental Solutions Initiative; and the nonprofit The Sustainability Consortium, these companies are seeking a prototype sorting technology to bring to recycling facilities for large-scale testing and commercial development.

Working in Olsen’s lab, Hocken is coming to grips with the complexity of the recycling systems involved. Material recovery facilities, or MRFs, are expected to handle products in any number of shapes, sizes, and materials, and sort them into a pure stream of glass, metal, paper, or plastic. Hocken’s first step in taking on the recycling project was to tour one of these MRFs in Portland, Maine, with Olsen and Plata.

“We could literally see plastics just falling from the conveyor belts,” she says. “Leaving that tour, I thought, my gosh! There’s so much improvement that can be made. There’s so much impact that we can have on this industry.”

From designing plastics to managing them

Hocken always knew she wanted to work in engineering. Growing up in Scottsdale, Arizona, she was able to spend time in the workplace with her father, an electrical engineer who designs biomedical devices. “Seeing him working as an engineer, and how he’s solving these really important problems, definitely sparked my interest,” she says. “When it came time to begin my undergraduate degree, it was a really easy decision to choose engineering after seeing the day-to-day that my dad was doing in his career.”

At Arizona State University, she settled on chemical engineering as a major and began working with polymers, coming up with combinations of additives for 3D plastics printing that could help fine-tune how the final products behaved. But even working with plastics every day, she rarely thought about the implications of her work for the environment.

“And then in the spring of my final year at ASU, I took a class about polymers through the lens of sustainability, and that really opened my eyes,” Hocken remembers. The class was taught by Professor Timothy Long, director of the Biodesign Center for Sustainable Macromolecular Materials and Manufacturing and a well-known expert in the field of sustainable plastics. “That first session, where he laid out all of the really scary facts surrounding the plastics crisis, got me very motivated to look more into that field.”

At MIT the next year, Hocken sought out Olsen as her advisor and made plastics sustainability her focus from the start.

“Coming to MIT was my first time venturing outside of the state of Arizona for more than a three-month period,” she says. “It’s been really fun. I love living in Cambridge and the Boston area. I love my labmates. Everyone is so supportive, whether it’s to give me advice about some science that I’m trying to figure out, or just give me a pep talk if I’m feeling a little discouraged.”

A challenge to recycle

A lot of plastics research today is devoted to creating new materials — including biodegradable ones that are easier for natural ecosystems to absorb, and highly recyclable ones that hold their properties better after being melted down and recast.

But Hocken also sees a huge need for better ways to handle the plastics we’re already making. “While biodegradable and sustainable polymers represent a very important route, and I think they should certainly be further pursued, we’re still a ways away from that being a reality universally across all plastic packaging,” she says. As long as large volumes of conventional plastic are coming out of factories, we’ll need innovative ways to stop it from piling onto the mountain of plastic pollution. In one of her projects, Hocken is trying to come up with new uses for recycled plastic that take advantage of its lost strength to produce a useful, flexible material similar to rubber.

The small-format recycling project also falls in this category. The companies supporting the project have challenged the MIT team to work with their products exactly as currently manufactured — especially because their competitors use similar packaging materials that will also need to be covered by any solution the MIT team devises.

The challenge is a large one. To kick the project off, the participating companies sent the MIT team a wide range of small-format products that need to make it through the sorting process. These include containers for lip balm, deodorant, pills, and shampoo, and disposable tools like toothbrushes and flossing picks. “A constraint, or problem I foresee, is just how variable the shapes are,” says Hocken. “A flossing pick versus a toothbrush are very different shapes.”

Nor are they all made of the same kind of plastic. Many are made of polyethylene terephthalate (PET, type 1 in the recycling label system) or high-density polyethylene (HDPE, type 2), but nearly all of the seven recycling categories are represented among the sample products. The team’s solution will have to handle them all.

Another obstacle is that the sorting process at a large MRF is already very complex and requires a heavy investment in equipment. The waste stream typically goes through a “glass breaker screen” that shatters glass and collects the shards; a series of rotating rubber stars to pull out two-dimensional objects, collecting paper and cardboard; a system of magnets and eddy currents to attract or repel different metals; and finally, a series of optical sorters that use infrared spectroscopy to identify the various types of plastics, then blow them down different chutes with jets of air. MRFs won’t be interested in adopting additional sorters unless they’re inexpensive and easy to fit into this elaborate stream.

“We’re interested in creating something that could be retrofitted into current technology and current infrastructure,” Hocken says.

Shared solutions

“Recycling is a really good example of where pre-competitive collaboration is needed,” says Jennifer Park, collective action manager at The Sustainability Consortium (TSC), who has been working with corporate stakeholders on small format recyclability and helped convene the sponsors of this project and organize their contributions. “Companies manufacturing these products recognize that they cannot shift entire systems on their own. Consistency around what is and is not recyclable is the only way to avoid confusion and drive impact at scale.

“Additionally, it is interesting that consumer packaged goods companies are sponsoring this research at MIT which is focused on MRF-level innovations. They’re investing in innovations that they hope will be adopted by the recycling industry to make progress on their own sustainability goals.”

Hocken believes that, despite the challenges, it’s well worth pursuing a technology that can keep small-format plastics from slipping through MRFs’ fingers.

“These are products that would be more recyclable if they were easier to sort,” she says. “The only thing that’s different is the size. So you can recycle both your large shampoo bottle and the small travel-size one at home, but the small one isn’t guaranteed to make it into a plastic bale at the end. If we can come up with a solution that specifically targets those while they’re still on the sorting line, they’re more likely to end up in those plastic bales at the end of the line, which can be sold to plastic reclaimers who can then use that material in new products.”

“TSC is really excited about this project and our collaboration with MIT,” adds Park. “Our project stakeholders are very dedicated to finding a solution.”

To learn more about this project, contact Christopher Noble, director of corporate engagement at the MIT Environmental Solutions Initiative. More

If your team cares about protecting the environment and lowering business costs, then an active recycling program for your workplace may be the answer. Recycling has become a serious agenda item for Australia’s business community, as regulations and public pressure mount on organisations to improve their environmental footprint. According to the HP Australia Environmental Sustainability […] More