Where economics and materials science meet
As a postdoc in the MIT Materials Systems Laboratory, Michele L. Bustamante works at the intersection of economics and materials science, creating models of supply and demand for raw materials important to high-tech, such as tellurium needed for thin-film solar cells and cobalt needed for lithium ion batteries.
Her experience over the last two years helped Bustamante to win a one-year Congressional Science and Engineering Fellowship, which begins in September, from the Materials Research Society (MRS) and The Minerals, Metals and Materials Society (TMS).
“I’ve worked with sponsors who are in the commodity industry, and they want to understand how are new things like renewable energy and electric and autonomous vehicles going to change demand for metals that they produce,” Bustamante explains. During her time at MIT, she has presented work at various conferences including the 2017 Materials Research Society Fall Meeting and a recent Industrial Liaison Program Summit at MIT. She collaborated with Materials Systems Laboratory Director Richard Roth, Principal Research Scientist Randolph E. Kirchain, and MSL Faculty Director Joel P. Clark, professor emeritus of materials systems.
Working closely with Roth, Bustamante says, she learned how to look at an abstract problem and break it down. “Even if we are uncertain about pieces of it, we can add value to the conversation, we can create a tool that allows us to draw conclusions that have value despite uncertainty,” she says. Together, they created a high-level framework that has the power to answer questions about innovative technologies and material commodities at the same time. Nobody really knows how many autonomous cars will be on the road in 2050, she suggests. But the models they build can estimate the opportunity for commodity demand growth by looking at factors such as how well the technology functions, affordability, alternatives that can be substituted or competing technologies that provide same function, and how large the technology’s market is expected to grow.
Bustamante’s work took a surprising turn when she explored the use of thinner and higher strength steels for Coast Guard and Navy ships at Huntington Ingalls Industries Shipbuilding Division in Pascagoula, Mississippi. The project, through the Lightweight Innovations for Tomorrow Initiative, took her to Mississippi many times, meeting on the ground with production crews. “This industry is as old as our country, and they are using a lot of lower tech manufacturing processes, because they are only making tens of ships of a certain class as opposed to the automotive industry where they are making millions each year,” Bustamante says.
Newer steels that are stronger and can be used at thinner gauge respond differently to these legacy manufacturing processes and can result in extreme waviness when two of the flat metal plates are welded together. “When you’re building a ship that’s going to be used for the military, you want to make sure the quality is really safe and so you can’t have that,” she says.
The MIT Materials Systems Lab was brought in for its expertise in understanding where economics and materials science meet. “Our role was to understand the manufacturing process, and use that to build a cost model to allow them to make this decision in an informed way. To understand, okay, it’s going to cost us X up front, but what kind of savings are we actually going to see down the line and is it something that we should be doing,” Bustamante explains. “That was a surprisingly fun project for me, and a great group of people that we got to work with. The kind of research that I’ve done [historically] has been very much in the lab on my computer, on the phone maybe with some other academics.”
For her most recent project, Bustamante worked with Tanguy Marion, a student in the MIT Technology and Policy Program, on looking at different types of lithium ion batteries that are being used in electric vehicles. Marion went to China, where he interviewed battery and electric vehicle manufacturers to learn how they decide which lithium ion battery technology to use, comparing iron versus phosphorus, and cobalt versus nickel. The MIT team is creating a model to predict the outlook for adoption of different materials. Bustamante also traveled to China last July and September for this work.
Bustamante, who has a longstanding interest in communicating science, says she was excited to find out that there are career paths at the interface of science and policy. She participated in the Kaufman Teaching Certificate Program at MIT this spring.
“The practice of teaching is inherently about communicating well and it’s about figuring out how to take something that I know and putting it in your head and getting you to understand it,” she says.
“I see this as a really cool opportunity to get out of the lab and see what people who are making decisions for our country are doing, or not doing, with this scientific information that I spend day in and day out reading about and producing,” Bustamante says. “Can we as scientists do a better job of communicating what we we’re doing and the societal benefits that they provide, so that we can actually implement a lot more of all the cool stuff that’s going on at MIT and otherwise?”
Smell of chocolate
Bustamante, 28, grew up in Hackettstown, New Jersey, where the smell of chocolate hung in the air from the M&M Mars factory, especially around Halloween. “You smell chocolate in the air from my house; that was always really cool,” she says.
After attending Warren Hills Regional High School, Bustamante went to Rensselaer Polytechnic Institute (RPI) in Troy, New York, where she completed her bachelor’s degree in environmental engineering and materials engineering in May 2012. “I have been someone who’s really interested in a lot of things and so I like to see what kind of opportunities present themselves and seize them when I can.”
Fun little puzzle
A summer undergraduate research opportunity at FREEDM Systems Center at North Carolina State University, challenged Bustamante to work on an electrical engineering project, helping to design a computer model for a rooftop solar panel array that she helped install. The model takes ambient conditions such as temperature, amount of solar radiation, and other outdoor conditions, and predicts expected solar panel output to aid in future research done with the array. “It was a fun little puzzle to actually implement that kind of a model, and it is not something I had ever done before, so I learned a ton,” Bustamante says.
A presentation by a materials scientist from ARPA-E that summer gave Bustamante insight into the role materials science could play reducing environmental impact from the outset of a product’s life versus the traditional environmental engineering approach of focusing on remediation at the end of it. “I just remember being like, wow, this is it, this is what I have been looking for, and I was so interested. I saw materials science as this amazing opportunity to be on the front lines of products and things we put into the environment from the get go,” she says. Bustamante pursued a double major at RPI in materials science and environmental engineering. “I realized toward the end of it that it was my attempt to create a program that didn’t exist in sustainability by looking at … improving environmental quality of things being put out there at the beginning of a life cycle as well as reducing environmental harm at the end of a product life cycle. That sort of life cycle thinking is exactly what sustainability is about,” she says.
Passion for sustainability
Bustamante sought inspiration at the Golisano Institute for Sustainability at Rochester Institute of Technology. “They were doing precisely the kind of work I wanted to do that looked at the intersection of manufacturing and technology production, environmental impact reduction, and just the whole life cycle, looking at things big picture,” she says. Bustamante found a mentor in RIT Associate Professor of Sustainability Gabrielle G. Gaustad SM '09, PhD '09, who was a graduate student in the MIT Materials Systems Laboratory before embarking on her academic career. “She was someone who still to this day inspires me,” says Bustamante, who was awarded her PhD at RIT in May 2016.
Bustamante and Gaustad tackled the complex issue of tellurium supply and its effect on solar panel industry growth. Unlike copper, a primary metal mined and processed for its widespread demand and multiple uses from electrical wire to cookware coatings, tellurium is a relatively rare element and is produced as a byproduct of copper refining. That means the market for tellurium is somewhat dependent on the market for copper. If there isn’t enough of a commodity being produced, prices will go up, and, in most commodity markets, such as copper, those higher prices will spur miners and refiners to increase supply. “But my perspective of the byproduct research is that natural feedback mechanism is really muted if you are a byproduct, and so for those specific kind of markets, we do need to pay a little bit more attention if we value the products that they are being used in and see the benefit that they’re bringing,” Bustamante explains.
“I did find that something that others hadn’t studied was when you mine copper, there is more than one way to do it, and only one of those ways actually yields this byproduct, tellurium. The other one does not,” she explains. The lower cost method, which is called solvent extraction and electrowinning (SX-EW), had been taking away some of the market share of production from the alternative method, called electrolytic refining, that does yield tellurium as a byproduct. “No one had really been looking at trends in the production [methods] of this main product and how that affects the availability of a byproduct,” Bustamante says. Understanding the details of supply and quantifying the scarcity of materials such as tellurium, which are critical to some new technologies, became the foundation of her research. From the perspective of risk, or criticality, three factors all must be considered: economic importance, supply security, and environmental impact, she says. Her dissertation work contributed to understanding each of these three factors.
Addressing the latter component, Bustamante and her colleagues were motivated by the question, “Can we do a better job of understanding the environmental impact? Because that also is something that people factor into this measure of criticality.” She explored this question through work focused on highlighting challenges and sharing best practices for people performing life cycle assessments [LCAs] of solar energy technologies based on byproduct materials, like tellurium. Life cycle assessment, which is similar to carbon footprinting, is widely used to compare the environmental friendliness of products. It is done by detailing the activities in a product life cycle — how the necessary raw materials are produced, manufactured into products, transported, used, and ultimately disposed of — to quantify environmental impact drivers such as energy or water use and chemical emissions. This technique requires accurate modeling of how raw materials, like tellurium, are produced to describe their environmental impact. However, a key challenge of assessing life cycle impacts of a particular product is deciding how much impact should be assigned to an indivdidual step in a process, such as mining, when there are multiple steps in a production process. This challenge is known in the LCA community as “the allocation problem.” Bustamante’s work demonstrated the impact of ignoring uncertainties in the current approaches, which are based on mass or economic value of the products in a fixed time frame, and suggested guidelines for practitioners to minimize their impact in a standardized way. This work was published in Solar Energy Materials and Solar Cells.
Considering supply security, Bustamante and Gaustad, along with fellow MSL alumna, Elisa Alonso PhD '09 developed a framework to compare the effectiveness of different solutions to criticality in a paper published last year in Environmental Science and Technology. For example, recovery of tellurium from recycling cadmium telluride solar panels could reduce supply risk. However, their work showed that this was not viable in the near future when criticality risks are likely to be highest because solar panels have an expected lifetime of about 25 years and most panels of this type were installed within the past decade. They also examined the effect of improving the percentage of tellurium successfully extracted from the mining process with promising results. Among these options, reducing demand by making solar material film thinner was shown to have the greatest benefit. Bustamante presented this work at the 2017 Materials Research Society Fall Meeting.
“What the best solution would be is to start making these panels more efficient, which is great because that’s already their goal, the companies who make these. If we can make them more efficient, then we get more power out of less material and reduce that demand in the short term,” Bustamante suggests.
Much like tellurium, rare earth materials such as dysprosium and neodymium, which are used in high-strength magnets for electric vehicle motors, wind turbines and other clean energy technologies, face market supply issues since almost all of the world’s rare earths still come form China.
“The more diversity we can get in the way those things are available, the less risk we face in price spikes for those, causing people not to be able to manufacture them and being too expensive to purchase, the technologies that are providing environmental benefit,” Bustamante says.
In graduate school, Bustamante helped launch RIT’s Food Recovery Network chapter as one of its first volunteers. During the four years that she was involved, the chapter worked with the school’s food vendors to recover more than 50,000 pounds of food and distribute it to food banks and churches serving the needy in Rochester. “The goal of that organization is to try to both eliminate food waste on college campuses as well as to reduce food insecurity in the community,” she explains. “We do that by creating relationships with the dining centers on campus and getting them to work with us to save leftover food that they have.” One in five children in Rochester is food insecure, meaning they don’t have consistent access to food, and especially nutritious food, Bustamante says, citing a Community Health Needs Assessment. A U.S. Department of Agriculture report estimates that 31 percent of food at the retail and consumer levels goes uneaten.
“It was a nice parallel to the research that I did because it had to do with an important material being supplied to society and being able to take a byproduct, something that was previously viewed as waste and being thrown away, and give it value and create a solution by just redefining what is actually waste and what is not waste,” Bustamante says. “It’s awesome when you can find opportunities that are such low hanging fruit for providing value,” says.
For her fellowship application, Bustamante drafted a policy memo examining the impact of solar tariffs, such as the one put in place by the Trump Administration in January 2018. “The tariff supposedly has the goal of helping the solar industry by making it more expensive to import cells and panels, incentivizing you to purchase local, but there is no local manufacturing infrastructure, and it takes time to build that up,” Bustamante explains. She thinks it is unlikely to occur over the four years the tariff will be in place declining from 30 percent in the first year to 15 percent in the fourth. “Undoubtedly, it’s going to raise their prices, so people will have to pay more if they want solar installed for the next four years, and that’s, of course, going to tip the scale for some people and some people are not going to install that otherwise would have been interested in it. So, I think long term it’s going to have a pretty minor effect, but the guise of helping the solar industry by incentivizing manufacturing is really not what’s going to be the impact of this tariff.”
Bustamante won’t learn until the fall which member of Congress or Congressional committee she will serve as a special legislative assistant. She’ll be joined in Washington by her husband, Justin Barends. After an orientation period, fellows are interviewed by Congressional offices to see where their skills and interest fit best. “Generally people end up in offices with people that they largely align with politically, which seems prudent,” Bustamante says. “I would like to work with someone who represents an area that I’ve lived in.”
“I see my role as an opportunity to provide information and advocate for what the science is saying on a certain issue and trying to put that voice out there more, but at the end of the day I know that I’m not going to change politics. People are going to do what’s in their best interests. All I can to do is just keep trying and learning, and learning how that works and what people’s motivations are, so that I can do it better in the future,” Bustamante says.
“I’m bringing my background and my network in the scientific community, but it’s also geared towards being a learning experience,” she says. “So if I can get anything at all accomplished that I feel really proud of, great. But I’m also going to be learning a lot through successes and failures, and hopefully that will lead to better success for the future.”