Greenhouse gases

Subterms

    More stories

    • 75 Shares169 Views

      in Energy

      Turning carbon dioxide into valuable products

      by

      Carbon dioxide (CO2) is a major contributor to climate change and a significant product of many human activities, notably industrial manufacturing. A major goal in the energy field has been to chemically convert emitted CO2 into valuable chemicals or fuels. But while CO2 is available in abundance, it has not yet been widely used to generate value-added products. Why not?

      The reason is that CO2 molecules are highly stable and therefore not prone to being chemically converted to a different form. Researchers have sought materials and device designs that could help spur that conversion, but nothing has worked well enough to yield an efficient, cost-effective system.

      Two years ago, Ariel Furst, the Raymond (1921) and Helen St. Laurent Career Development Professor of Chemical Engineering at MIT, decided to try using something different — a material that gets more attention in discussions of biology than of chemical engineering. Already, results from work in her lab suggest that her unusual approach is paying off.

      The stumbling block

      The challenge begins with the first step in the CO2 conversion process. Before being transformed into a useful product, CO2 must be chemically converted into carbon monoxide (CO). That conversion can be encouraged using electrochemistry, a process in which input voltage provides the extra energy needed to make the stable CO2 molecules react. The problem is that achieving the CO2-to-CO conversion requires large energy inputs — and even then, CO makes up only a small fraction of the products that are formed.

      To explore opportunities for improving this process, Furst and her research group focused on the electrocatalyst, a material that enhances the rate of a chemical reaction without being consumed in the process. The catalyst is key to successful operation. Inside an electrochemical device, the catalyst is often suspended in an aqueous (water-based) solution. When an electric potential (essentially a voltage) is applied to a submerged electrode, dissolved CO2 will — helped by the catalyst — be converted to CO.

      But there’s one stumbling block: The catalyst and the CO2 must meet on the surface of the electrode for the reaction to occur. In some studies, the catalyst is dispersed in the solution, but that approach requires more catalyst and isn’t very efficient, according to Furst. “You have to both wait for the diffusion of CO2 to the catalyst and for the catalyst to reach the electrode before the reaction can occur,” she explains. As a result, researchers worldwide have been exploring different methods of “immobilizing” the catalyst on the electrode.

      Connecting the catalyst and the electrode

      Before Furst could delve into that challenge, she needed to decide which of the two types of CO2 conversion catalysts to work with: the traditional solid-state catalyst or a catalyst made up of small molecules. In examining the literature, she concluded that small-molecule catalysts held the most promise. While their conversion efficiency tends to be lower than that of solid-state versions, molecular catalysts offer one important advantage: They can be tuned to emphasize reactions and products of interest.

      Two approaches are commonly used to immobilize small-molecule catalysts on an electrode. One involves linking the catalyst to the electrode by strong covalent bonds — a type of bond in which atoms share electrons; the result is a strong, essentially permanent connection. The other sets up a non-covalent attachment between the catalyst and the electrode; unlike a covalent bond, this connection can easily be broken.

      Neither approach is ideal. In the former case, the catalyst and electrode are firmly attached, ensuring efficient reactions; but when the activity of the catalyst degrades over time (which it will), the electrode can no longer be accessed. In the latter case, a degraded catalyst can be removed; but the exact placement of the small molecules of the catalyst on the electrode can’t be controlled, leading to an inconsistent, often decreasing, catalytic efficiency — and simply increasing the amount of catalyst on the electrode surface without concern for where the molecules are placed doesn’t solve the problem.

      What was needed was a way to position the small-molecule catalyst firmly and accurately on the electrode and then release it when it degrades. For that task, Furst turned to what she and her team regard as a kind of “programmable molecular Velcro”: deoxyribonucleic acid, or DNA.

      Adding DNA to the mix

      Mention DNA to most people, and they think of biological functions in living things. But the members of Furst’s lab view DNA as more than just genetic code. “DNA has these really cool physical properties as a biomaterial that people don’t often think about,” she says. “DNA can be used as a molecular Velcro that can stick things together with very high precision.”

      Furst knew that DNA sequences had previously been used to immobilize molecules on surfaces for other purposes. So she devised a plan to use DNA to direct the immobilization of catalysts for CO2 conversion.

      Her approach depends on a well-understood behavior of DNA called hybridization. The familiar DNA structure is a double helix that forms when two complementary strands connect. When the sequence of bases (the four building blocks of DNA) in the individual strands match up, hydrogen bonds form between complementary bases, firmly linking the strands together.

      Using that behavior for catalyst immobilization involves two steps. First, the researchers attach a single strand of DNA to the electrode. Then they attach a complementary strand to the catalyst that is floating in the aqueous solution. When the latter strand gets near the former, the two strands hybridize; they become linked by multiple hydrogen bonds between properly paired bases. As a result, the catalyst is firmly affixed to the electrode by means of two interlocked, self-assembled DNA strands, one connected to the electrode and the other to the catalyst.

      Better still, the two strands can be detached from one another. “The connection is stable, but if we heat it up, we can remove the secondary strand that has the catalyst on it,” says Furst. “So we can de-hybridize it. That allows us to recycle our electrode surfaces — without having to disassemble the device or do any harsh chemical steps.”

      Experimental investigation

      To explore that idea, Furst and her team — postdocs Gang Fan and Thomas Gill, former graduate student Nathan Corbin PhD ’21, and former postdoc Amruta Karbelkar — performed a series of experiments using three small-molecule catalysts based on porphyrins, a group of compounds that are biologically important for processes ranging from enzyme activity to oxygen transport. Two of the catalysts involve a synthetic porphyrin plus a metal center of either cobalt or iron. The third catalyst is hemin, a natural porphyrin compound used to treat porphyria, a set of disorders that can affect the nervous system. “So even the small-molecule catalysts we chose are kind of inspired by nature,” comments Furst.

      In their experiments, the researchers first needed to modify single strands of DNA and deposit them on one of the electrodes submerged in the solution inside their electrochemical cell. Though this sounds straightforward, it did require some new chemistry. Led by Karbelkar and third-year undergraduate researcher Rachel Ahlmark, the team developed a fast, easy way to attach DNA to electrodes. For this work, the researchers’ focus was on attaching DNA, but the “tethering” chemistry they developed can also be used to attach enzymes (protein catalysts), and Furst believes it will be highly useful as a general strategy for modifying carbon electrodes.

      Once the single strands of DNA were deposited on the electrode, the researchers synthesized complementary strands and attached to them one of the three catalysts. When the DNA strands with the catalyst were added to the solution in the electrochemical cell, they readily hybridized with the DNA strands on the electrode. After half-an-hour, the researchers applied a voltage to the electrode to chemically convert CO2 dissolved in the solution and used a gas chromatograph to analyze the makeup of the gases produced by the conversion.

      The team found that when the DNA-linked catalysts were freely dispersed in the solution, they were highly soluble — even when they included small-molecule catalysts that don’t dissolve in water on their own. Indeed, while porphyrin-based catalysts in solution often stick together, once the DNA strands were attached, that counterproductive behavior was no longer evident.

      The DNA-linked catalysts in solution were also more stable than their unmodified counterparts. They didn’t degrade at voltages that caused the unmodified catalysts to degrade. “So just attaching that single strand of DNA to the catalyst in solution makes those catalysts more stable,” says Furst. “We don’t even have to put them on the electrode surface to see improved stability.” When converting CO2 in this way, a stable catalyst will give a steady current over time. Experimental results showed that adding the DNA prevented the catalyst from degrading at voltages of interest for practical devices. Moreover, with all three catalysts in solution, the DNA modification significantly increased the production of CO per minute.

      Allowing the DNA-linked catalyst to hybridize with the DNA connected to the electrode brought further improvements, even compared to the same DNA-linked catalyst in solution. For example, as a result of the DNA-directed assembly, the catalyst ended up firmly attached to the electrode, and the catalyst stability was further enhanced. Despite being highly soluble in aqueous solutions, the DNA-linked catalyst molecules remained hybridized at the surface of the electrode, even under harsh experimental conditions.

      Immobilizing the DNA-linked catalyst on the electrode also significantly increased the rate of CO production. In a series of experiments, the researchers monitored the CO production rate with each of their catalysts in solution without attached DNA strands — the conventional setup — and then with them immobilized by DNA on the electrode. With all three catalysts, the amount of CO generated per minute was far higher when the DNA-linked catalyst was immobilized on the electrode.

      In addition, immobilizing the DNA-linked catalyst on the electrode greatly increased the “selectivity” in terms of the products. One persistent challenge in using CO2 to generate CO in aqueous solutions is that there is an inevitable competition between the formation of CO and the formation of hydrogen. That tendency was eased by adding DNA to the catalyst in solution — and even more so when the catalyst was immobilized on the electrode using DNA. For both the cobalt-porphyrin catalyst and the hemin-based catalyst, the formation of CO relative to hydrogen was significantly higher with the DNA-linked catalyst on the electrode than in solution. With the iron-porphyrin catalyst they were about the same. “With the iron, it doesn’t matter whether it’s in solution or on the electrode,” Furst explains. “Both of them have selectivity for CO, so that’s good, too.”

      Progress and plans

      Furst and her team have now demonstrated that their DNA-based approach combines the advantages of the traditional solid-state catalysts and the newer small-molecule ones. In their experiments, they achieved the highly efficient chemical conversion of CO2 to CO and also were able to control the mix of products formed. And they believe that their technique should prove scalable: DNA is inexpensive and widely available, and the amount of catalyst required is several orders of magnitude lower when it’s immobilized using DNA.

      Based on her work thus far, Furst hypothesizes that the structure and spacing of the small molecules on the electrode may directly impact both catalytic efficiency and product selectivity. Using DNA to control the precise positioning of her small-molecule catalysts, she plans to evaluate those impacts and then extrapolate design parameters that can be applied to other classes of energy-conversion catalysts. Ultimately, she hopes to develop a predictive algorithm that researchers can use as they design electrocatalytic systems for a wide variety of applications.

      This research was supported by a grant from the MIT Energy Initiative Seed Fund.

      This article appears in the Spring 2022 issue of Energy Futures, the magazine of the MIT Energy Initiative. More

    • 150 Shares159 Views

      in Energy

      Stranded assets could exact steep costs on fossil energy producers and investors

      by

      A 2021 study in the journal Nature found that in order to avert the worst impacts of climate change, most of the world’s known fossil fuel reserves must remain untapped. According to the study, 90 percent of coal and nearly 60 percent of oil and natural gas must be kept in the ground in order to maintain a 50 percent chance that global warming will not exceed 1.5 degrees Celsius above preindustrial levels.

      As the world transitions away from greenhouse-gas-emitting activities to keep global warming well below 2 C (and ideally 1.5 C) in alignment with the Paris Agreement on climate change, fossil fuel companies and their investors face growing financial risks (known as transition risks), including the prospect of ending up with massive stranded assets. This ongoing transition is likely to significantly scale back fossil fuel extraction and coal-fired power plant operations, exacting steep costs — most notably asset value losses — on fossil-energy producers and shareholders.

      Now, a new study in the journal Climate Change Economics led by researchers at the MIT Joint Program on the Science and Policy of Global Change estimates the current global asset value of untapped fossil fuels through 2050 under four increasingly ambitious climate-policy scenarios. The least-ambitious scenario (“Paris Forever”) assumes that initial Paris Agreement greenhouse gas emissions-reduction pledges are upheld in perpetuity; the most stringent scenario (“Net Zero 2050”) adds coordinated international policy instruments aimed at achieving global net-zero emissions by 2050.

      Powered by the MIT Joint Program’s model of the world economy with detailed representation of the energy sector and energy industry assets over time, the study finds that the global net present value of untapped fossil fuel output through 2050 relative to a reference “No Policy” scenario ranges from $21.5 trillion (Paris Forever) to $30.6 trillion (Net Zero 2050). The estimated global net present value of stranded assets in coal power generation through 2050 ranges from $1.3 to $2.3 trillion.

      “The more stringent the climate policy, the greater the volume of untapped fossil fuels, and hence the higher the potential asset value loss for fossil-fuel owners and investors,” says Henry Chen, a research scientist at the MIT Joint Program and the study’s lead author.

      The global economy-wide analysis presented in the study provides a more fine-grained assessment of stranded assets than those performed in previous studies. Firms and financial institutions may combine the MIT analysis with details on their own investment portfolios to assess their exposure to climate-related transition risk. More

    • 100 Shares129 Views

      in Energy

      Getting the carbon out of India’s heavy industries

      by

      The world’s third largest carbon emitter after China and the United States, India ranks seventh in a major climate risk index. Unless India, along with the nearly 200 other signatory nations of the Paris Agreement, takes aggressive action to keep global warming well below 2 degrees Celsius relative to preindustrial levels, physical and financial losses from floods, droughts, and cyclones could become more severe than they are today. So, too, could health impacts associated with the hazardous air pollution levels now affecting more than 90 percent of its population.  

      To address both climate and air pollution risks and meet its population’s escalating demand for energy, India will need to dramatically decarbonize its energy system in the coming decades. To that end, its initial Paris Agreement climate policy pledge calls for a reduction in carbon dioxide intensity of GDP by 33-35 percent by 2030 from 2005 levels, and an increase in non-fossil-fuel-based power to about 40 percent of cumulative installed capacity in 2030. At the COP26 international climate change conference, India announced more aggressive targets, including the goal of achieving net-zero emissions by 2070.

      Meeting its climate targets will require emissions reductions in every economic sector, including those where emissions are particularly difficult to abate. In such sectors, which involve energy-intensive industrial processes (production of iron and steel; nonferrous metals such as copper, aluminum, and zinc; cement; and chemicals), decarbonization options are limited and more expensive than in other sectors. Whereas replacing coal and natural gas with solar and wind could lower carbon dioxide emissions in electric power generation and transportation, no easy substitutes can be deployed in many heavy industrial processes that release CO2 into the air as a byproduct.

      However, other methods could be used to lower the emissions associated with these processes, which draw upon roughly 50 percent of India’s natural gas, 25 percent of its coal, and 20 percent of its oil. Evaluating the potential effectiveness of such methods in the next 30 years, a new study in the journal Energy Economics led by researchers at the MIT Joint Program on the Science and Policy of Global Change is the first to explicitly explore emissions-reduction pathways for India’s hard-to-abate sectors.

      Using an enhanced version of the MIT Economic Projection and Policy Analysis (EPPA) model, the study assesses existing emissions levels in these sectors and projects how much they can be reduced by 2030 and 2050 under different policy scenarios. Aimed at decarbonizing industrial processes, the scenarios include the use of subsidies to increase electricity use, incentives to replace coal with natural gas, measures to improve industrial resource efficiency, policies to put a price on carbon, carbon capture and storage (CCS) technology, and hydrogen in steel production.

      The researchers find that India’s 2030 Paris Agreement pledge may still drive up fossil fuel use and associated greenhouse gas emissions, with projected carbon dioxide emissions from hard-to-abate sectors rising by about 2.6 times from 2020 to 2050. But scenarios that also promote electrification, natural gas support, and resource efficiency in hard-to-abate sectors can lower their CO2 emissions by 15-20 percent.

      While appearing to move the needle in the right direction, those reductions are ultimately canceled out by increased demand for the products that emerge from these sectors. So what’s the best path forward?

      The researchers conclude that only the incentive of carbon pricing or the advance of disruptive technology can move hard-to-abate sector emissions below their current levels. To achieve significant emissions reductions, they maintain, the price of carbon must be high enough to make CCS economically viable. In that case, reductions of 80 percent below current levels could be achieved by 2050.

      “Absent major support from the government, India will be unable to reduce carbon emissions in its hard-to-abate sectors in alignment with its climate targets,” says MIT Joint Program deputy director Sergey Paltsev, the study’s lead author. “A comprehensive government policy could provide robust incentives for the private sector in India and generate favorable conditions for foreign investments and technology advances. We encourage decision-makers to use our findings to design efficient pathways to reduce emissions in those sectors, and thereby help lower India’s climate and air pollution-related health risks.” More

    • 63 Shares99 Views

      in Energy

      Making hydrogen power a reality

      by

      For decades, government and industry have looked to hydrogen as a potentially game-changing tool in the quest for clean energy. As far back as the early days of the Clinton administration, energy sector observers and public policy experts have extolled the virtues of hydrogen — to the point that some people have joked that hydrogen is the energy of the future, “and always will be.”

      Even as wind and solar power have become commonplace in recent years, hydrogen has been held back by high costs and other challenges. But the fuel may finally be poised to have its moment. At the MIT Energy Initiative Spring Symposium — entitled “Hydrogen’s role in a decarbonized energy system” — experts discussed hydrogen production routes, hydrogen consumption markets, the path to a robust hydrogen infrastructure, and policy changes needed to achieve a “hydrogen future.”

      During one panel, “Options for producing low-carbon hydrogen at scale,” four experts laid out existing and planned efforts to leverage hydrogen for decarbonization. 

      “The race is on”

      Huyen N. Dinh, a senior scientist and group manager at the National Renewable Energy Laboratory (NREL), is the director of HydroGEN, a consortium of several U.S. Department of Energy (DOE) national laboratories that accelerates research and development of innovative and advanced water splitting materials and technologies for clean, sustainable, and low-cost hydrogen production.

      For the past 14 years, Dinh has worked on fuel cells and hydrogen production for NREL. “We think that the 2020s is the decade of hydrogen,” she said. Dinh believes that the energy carrier is poised to come into its own over the next few years, pointing to several domestic and international activities surrounding the fuel and citing a Hydrogen Council report that projected the future impacts of hydrogen — including 30 million jobs and $2.5 trillion in global revenue by 2050.

      “Now is the time for hydrogen, and the global race is on,” she said.

      Dinh also explained the parameters of the Hydrogen Shot — the first of the DOE’s “Energy Earthshots” aimed at accelerating breakthroughs for affordable and reliable clean energy solutions. Hydrogen fuel currently costs around $5 per kilogram to produce, and the Hydrogen Shot’s stated goal is to bring that down by 80 percent to $1 per kilogram within a decade.

      The Hydrogen Shot will be facilitated by $9.5 billion in funding for at least four clean hydrogen hubs located in different parts of the United States, as well as extensive research and development, manufacturing, and recycling from last year’s bipartisan infrastructure law. Still, Dinh noted that it took more than 40 years for solar and wind power to become cost competitive, and now industry, government, national lab, and academic leaders are hoping to achieve similar reductions in hydrogen fuel costs over a much shorter time frame. In the near term, she said, stakeholders will need to improve the efficiency, durability, and affordability of hydrogen production through electrolysis (using electricity to split water) using today’s renewable and nuclear power sources. Over the long term, the focus may shift to splitting water more directly through heat or solar energy, she said.

      “The time frame is short, the competition is intense, and a coordinated effort is critical for domestic competitiveness,” Dinh said.

      Hydrogen across continents

      Wambui Mutoru, principal engineer for international commercial development, exploration, and production international at the Norwegian global energy company Equinor, said that hydrogen is an important component in the company’s ambitions to be carbon-neutral by 2050. The company, in collaboration with partners, has several hydrogen projects in the works, and Mutoru laid out the company’s Hydrogen to Humber project in Northern England. Currently, the Humber region emits more carbon dioxide than any other industrial cluster in the United Kingdom — 50 percent more, in fact, than the next-largest carbon emitter.   

      “The ambition here is for us to deploy the world’s first at-scale hydrogen value chain to decarbonize the Humber industrial cluster,” Mutoru said.

      The project consists of three components: a clean hydrogen production facility, an onshore hydrogen and carbon dioxide transmission network, and offshore carbon dioxide transportation and storage operations. Mutoru highlighted the importance of carbon capture and storage in hydrogen production. Equinor, she said, has captured and sequestered carbon offshore for more than 25 years, storing more than 25 million tons of carbon dioxide during that time.

      Mutoru also touched on Equinor’s efforts to build a decarbonized energy hub in the Appalachian region of the United States, covering territory in Ohio, West Virginia, and Pennsylvania. By 2040, she said, the company’s ambition is to produce about 1.5 million tons of clean hydrogen per year in the region — roughly equivalent to 6.8 gigawatts of electricity — while also storing 30 million tons of carbon dioxide.

      Mutoru acknowledged that the biggest challenge facing potential hydrogen producers is the current lack of viable business models. “Resolving that challenge requires cross-industry collaboration, and supportive policy frameworks so that the market for hydrogen can be built and sustained over the long term,” she said.

      Confronting barriers

      Gretchen Baier, executive external strategy and communications leader for Dow, noted that the company already produces hydrogen in multiple ways. For one, Dow operates the world’s largest ethane cracker, in Texas. An ethane cracker heats ethane to break apart molecular bonds to form ethylene, with hydrogen one of the byproducts of the process. Also, Baier showed a slide of the 1891 patent for the electrolysis of brine water, which also produces hydrogen. The company still engages in this practice, but Dow does not have an effective way of utilizing the resulting hydrogen for their own fuel.

      “Just take a moment to think about that,” Baier said. “We’ve been talking about hydrogen production and the cost of it, and this is basically free hydrogen. And it’s still too much of a barrier to somewhat recycle that and use it for ourselves. The environment is clearly changing, and we do have plans for that, but I think that kind of sets some of the challenges that face industry here.”

      However, Baier said, hydrogen is expected to play a significant role in Dow’s future as the company attempts to decarbonize by 2050. The company, she said, plans to optimize hydrogen allocation and production, retrofit turbines for hydrogen fueling, and purchase clean hydrogen. By 2040, Dow expects more than 60 percent of its sites to be hydrogen-ready.

      Baier noted that hydrogen fuel is not a “panacea,” but rather one among many potential contributors as industry attempts to reduce or eliminate carbon emissions in the coming decades. “Hydrogen has an important role, but it’s not the only answer,” she said.

      “This is real”

      Colleen Wright is vice president of corporate strategy for Constellation, which recently separated from Exelon Corporation. (Exelon now owns the former company’s regulated utilities, such as Commonwealth Edison and Baltimore Gas and Electric, while Constellation owns the competitive generation and supply portions of the business.) Wright stressed the advantages of nuclear power in hydrogen production, which she said include superior economics, low barriers to implementation, and scalability.

      “A quarter of emissions in the world are currently from hard-to-decarbonize sectors — the industrial sector, steel making, heavy-duty transportation, aviation,” she said. “These are really challenging decarbonization sectors, and as we continue to expand and electrify, we’re going to need more supply. We’re also going to need to produce clean hydrogen using emissions-free power.”

      “The scale of nuclear power plants is uniquely suited to be able to scale hydrogen production,” Wright added. She mentioned Constellation’s Nine Mile Point site in the State of New York, which received a DOE grant for a pilot program that will see a proton exchange membrane electrolyzer installed at the site.

      “We’re very excited to see hydrogen go from a [research and development] conversation to a commercial conversation,” she said. “We’ve been calling it a little bit of a ‘middle-school dance.’ Everybody is standing around the circle, waiting to see who’s willing to put something at stake. But this is real. We’re not dancing around the edges. There are a lot of people who are big players, who are willing to put skin in the game today.” More

    • 138 Shares189 Views

      in Environment

      Living Climate Futures initiative showcases holistic approach to the climate crisis

      by

      The sun shone bright and warm on the Dertouzos Amphitheater at the Stata Center this past Earth Day as a panel of Indigenous leaders from across the country talked about their experiences with climate activism and shared their natural world philosophies — a worldview that sees humanity as one with the rest of the Earth.

      “I was taught the natural world philosophies by those raised by precolonial individuals,” said Jay Julius W’tot Lhem of the Lummi tribe of the Pacific Northwest and founder and president of Se’Si’Le, an organization dedicated to reintroducing Indigenous spiritual law into the mainstream conversation about climate. Since his great-grandmother was born in 1888, he grew up “one hug away from pre-contact,” as he put it.

      Natural world philosophiesNatural world philosophies sit at the center of the Indigenous activism taking place all over the country, and they were a highlight of the Indigenous Earth Day panel — one part of a two-day symposium called Living Climate Futures. The events were hosted by the Anthropology and History sections and the Program on Science, Technology, and Society in MIT’s School of Humanities, Arts, and Social Sciences (SHASS), in collaboration with the MIT Office of Sustainability and Project Indigenous MIT.

      “The Living Climate Futures initiative began from the recognition that the people who are living most closely with climate and environmental struggles and injustices are especially equipped to lead the way toward other ways of living in the world,” says Briana Meier, ACLS Emerging Voices Postdoctoral Fellow in Anthropology and an organizer of the event. “While much climate action is based in technology-driven policy, we recognize that solutions to climate change are often embedded within and produced in response to existing social systems of injustice and inequity.”

      On-the-ground experts from around the country spoke in a series of panels and discussions over the two days, sharing their stories and inspiring attendees to think differently about how to address the environmental crisis.

      Gathering experts

      The hope, according to faculty organizers, was that an event centered on such voices could create connections among activists and open the eyes of many to the human element of climate solutions.

      Over the years, many such solutions have overlooked the needs of the communities they are designed to help. Streams in the Pacific Northwest, for example, have been dammed to generate hydroelectric power — promoted as a green alternative to fossil fuel. But these same locations have long been sacred spots for Indigenous swimming rituals, said Ryan Emanuel (Lumbee), associate professor of hydrology at Duke University and a panelist in the Indigenous Earth Day event. Mitigating the environmental damage does not make up for the loss of sacred connection, he emphasized.

      To dig into such nuances, the organizers invited an intergenerational group of panelists to share successes with attendees.

      Transforming urban spaces

      In one panel, for example, urban farmers from Mansfield, Ohio, and Chelsea, Massachusetts, discussed the benefits of growing vegetables in cities.

      “Transforming urban spaces into farms provides not just healthy food, but a visible symbol of hope, a way for people to connect and grow food that reflects their cultures and homes, an economic development opportunity, and even a safe space for teens to hang out,” said Susy Jones, senior sustainability project manager in the MIT Office of Sustainability and an event organizer. “We also heard about the challenges — like the cost of real estate in Massachusetts.”

      Another panel highlighted the determined efforts of a group of students from George Washington High School in Southeast Chicago to derail a project to build a scrap metal recycling plant across the street from their school. “We’re at school eight hours a day,” said Gregory Miller, a junior at the school. “We refuse to live next door to a metals scrapyard.”

      The proposed plant was intended to replace something similar that had been shut down in a predominantly white neighborhood due to its many environmental violations. Southeast Chicago is more culturally diverse and has long suffered from industrial pollution and economic hardship, but the students fought the effort to further pollute their home — and won.

      “It was hard, the campaign,” said Destiny Vasquez. “But it was beautiful because the community came together. There is unity in our struggle.”

      Recovering a common heritage 

      Unity was also at the forefront of the discussion for the Indigenous Earth Day panel in the Stata Amphitheater. This portion of the Living Climate Futures event began with a greeting in the Navajo language from Alvin Harvey, PhD candidate in aeronautics and astronautics (Aero/Astro) and representative of the MIT American Indian Science and Engineering Society and the MIT Native American Student Association. The greeting identified all who came to the event as relatives.

      “Look at the relatives next to you, especially those trees,” he said, gesturing to the budding branches around the amphitheater. “They give you shelter, love … few other beings are willing to do that.”

      According to Julius, such reverence for nature is part of the Indigenous way of life, common across tribal backgrounds — and something all of humanity once had in common. “Somewhere along the line we all had Indigenous philosophies,” he said. “We all need an invitation back to that to understand we’re all part of the whole.”

      Understanding the oneness of all living things on earth helps people of Indigenous nations feel the distress of the earth when it is under attack, speakers said. Donna Chavis, senior climate campaigner for Friends of the Earth and an elder of the Lumbee tribe, discussed the trauma of having forests near her home in the southeastern United States clear-cut to provide wood chips to Europe.

      “They are devastating the lungs of the earth in North Carolina at a rate faster than in the Amazon,” she said. “You can almost hear the pain of the forest.”

      Small pictures of everyday life

      “People are experiencing a climate crisis that is global in really different ways in different places,” says Heather Paxson, head of MIT Anthropology and an event organizer. “What came out of these two days is a real, palpable sense of the power of listening to individual experience. Not because it gives us the big picture, but because it gives us the small picture.”

      Trinity Colón, one of the leaders of the group from George Washington High School, impressed on attendees that environmental justice is much more than an academic pursuit. “We’re not talking about climate change in the sense of statistics, infographics,” she said. “For us this is everyday life … [Future engineers and others training at MIT] should definitely take that into perspective, that these are real people really being affected by these injustices.”

      That call to action has already been felt by many at MIT.

      “I’ve been hearing from grad students lately, in engineering, saying, ‘I like thinking about these problems, but I don’t like where I’m being directed to use my intellectual capital, toward building more corporate wealth,’” said Kate Brown, professor of STS and an event organizer. “As an institution, we could move toward working not for, not to correct, but working with communities.”

      The world is what we’ve gotMIT senior Abdulazeez Mohammed Salim, an Aero/Astro major, says he was inspired by these conversations to get involved in urban farming initiatives in Baltimore, Maryland, where he plans to move after graduation.

      “We have a responsibility as part of the world around us, not as external observers, not as people removed and displaced from the world. And the world is not an experiment or a lab,” he says. “It’s what we’ve got. It’s who we are. It’s all that we’ve been and all we will be. That stuck with me; it resonated very deeply.”

      Salim also appreciated the reality check given by Bianca Bowman from GreenRoots Chelsea, who pointed out that success will not come quickly, and that sustained advocacy is critical.

      “Real, valuable change will not happen overnight, will not happen by just getting together a critical mass of people who are upset and concerned,” he said. “Because what we’re dealing with are large, interconnected, messy systems that will try to fight back and survive regardless of how we force them to adapt. And so, long term is really the only way forward. That’s the way we need to think of these struggles.” More

    • 88 Shares149 Views

      in Environment

      MIT J-WAFS announces 2022 seed grant recipients

      by

      The Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) at MIT has awarded eight MIT principal investigators with 2022 J-WAFS seed grants. The grants support innovative MIT research that has the potential to have significant impact on water- and food-related challenges.

      The only program at MIT that is dedicated to water- and food-related research, J-WAFS has offered seed grant funding to MIT principal investigators and their teams for the past eight years. The grants provide up to $75,000 per year, overhead-free, for two years to support new, early-stage research in areas such as water and food security, safety, supply, and sustainability. Past projects have spanned many diverse disciplines, including engineering, science, technology, and business innovation, as well as social science and economics, architecture, and urban planning. 

      Seven new projects led by eight researchers will be supported this year. With funding going to four different MIT departments, the projects address a range of challenges by employing advanced materials, technology innovations, and new approaches to resource management. The new projects aim to remove harmful chemicals from water sources, develop drought monitoring systems for farmers, improve management of the shellfish industry, optimize water purification materials, and more.

      “Climate change, the pandemic, and most recently the war in Ukraine have exacerbated and put a spotlight on the serious challenges facing global water and food systems,” says J-WAFS director John H. Lienhard. He adds, “The proposals chosen this year have the potential to create measurable, real-world impacts in both the water and food sectors.”  

      The 2022 J-WAFS seed grant researchers and their projects are:

      Gang Chen, the Carl Richard Soderberg Professor of Power Engineering in MIT’s Department of Mechanical Engineering, is using sunlight to desalinate water. The use of solar energy for desalination is not a new idea, particularly solar thermal evaporation methods. However, the solar thermal evaporation process has an overall low efficiency because it relies on breaking hydrogen bonds among individual water molecules, which is very energy-intensive. Chen and his lab recently discovered a photomolecular effect that dramatically lowers the energy required for desalination. 

      The bonds among water molecules inside a water cluster in liquid water are mostly hydrogen bonds. Chen discovered that a photon with energy larger than the bonding energy between the water cluster and the remaining water liquids can cleave off the water cluster at the water-air interface, colliding with air molecules and disintegrating into 60 or even more individual water molecules. This effect has the potential to significantly boost clean water production via new desalination technology that produces a photomolecular evaporation rate that exceeds pure solar thermal evaporation by at least ten-fold. 

      John E. Fernández is the director of the MIT Environmental Solutions Initiative (ESI) and a professor in the Department of Architecture, and also affiliated with the Department of Urban Studies and Planning. Fernández is working with Scott D. Odell, a postdoc in the ESI, to better understand the impacts of mining and climate change in water-stressed regions of Chile.

      The country of Chile is one of the world’s largest exporters of both agricultural and mineral products; however, little research has been done on climate change effects at the intersection of these two sectors. Fernández and Odell will explore how desalination is being deployed by the mining industry to relieve pressure on continental water supplies in Chile, and with what effect. They will also research how climate change and mining intersect to affect Andean glaciers and agricultural communities dependent upon them. The researchers intend for this work to inform policies to reduce social and environmental harms from mining, desalination, and climate change.

      Ariel L. Furst is the Raymond (1921) and Helen St. Laurent Career Development Professor of Chemical Engineering at MIT. Her 2022 J-WAFS seed grant project seeks to effectively remove dangerous and long-lasting chemicals from water supplies and other environmental areas. 

      Perfluorooctanoic acid (PFOA), a component of Teflon, is a member of a group of chemicals known as per- and polyfluoroalkyl substances (PFAS). These human-made chemicals have been extensively used in consumer products like nonstick cooking pans. Exceptionally high levels of PFOA have been measured in water sources near manufacturing sites, which is problematic as these chemicals do not readily degrade in our bodies or the environment. The majority of humans have detectable levels of PFAS in their blood, which can lead to significant health issues including cancer, liver damage, and thyroid effects, as well as developmental effects in infants. Current remediation methods are limited to inefficient capture and are mostly confined to laboratory settings. Furst’s proposed method utilizes low-energy, scaffolded enzyme materials to move beyond simple capture to degrade these hazardous pollutants.

      Heather J. Kulik is an associate professor in the Department of Chemical Engineering at MIT who is developing novel computational strategies to identify optimal materials for purifying water. Water treatment requires purification by selectively separating small ions from water. However, human-made, scalable materials for water purification and desalination are often not stable in typical operating conditions and lack precision pores for good separation. 

      Metal-organic frameworks (MOFs) are promising materials for water purification because their pores can be tailored to have precise shapes and chemical makeup for selective ion affinity. Yet few MOFs have been assessed for their properties relevant to water purification. Kulik plans to use virtual high-throughput screening accelerated by machine learning models and molecular simulation to accelerate discovery of MOFs. Specifically, Kulik will be looking for MOFs with ultra-stable structures in water that do not break down at certain temperatures. 

      Gregory C. Rutledge is the Lammot du Pont Professor of Chemical Engineering at MIT. He is leading a project that will explore how to better separate oils from water. This is an important problem to solve given that industry-generated oil-contaminated water is a major source of pollution to the environment.

      Emulsified oils are particularly challenging to remove from water due to their small droplet sizes and long settling times. Microfiltration is an attractive technology for the removal of emulsified oils, but its major drawback is fouling, or the accumulation of unwanted material on solid surfaces. Rutledge will examine the mechanism of separation behind liquid-infused membranes (LIMs) in which an infused liquid coats the surface and pores of the membrane, preventing fouling. Robustness of the LIM technology for removal of different types of emulsified oils and oil mixtures will be evaluated. César Terrer is an assistant professor in the Department of Civil and Environmental Engineering whose J-WAFS project seeks to answer the question: How can satellite images be used to provide a high-resolution drought monitoring system for farmers? 

      Drought is recognized as one of the world’s most pressing issues, with direct impacts on vegetation that threaten water resources and food production globally. However, assessing and monitoring the impact of droughts on vegetation is extremely challenging as plants’ sensitivity to lack of water varies across species and ecosystems. Terrer will leverage a new generation of remote sensing satellites to provide high-resolution assessments of plant water stress at regional to global scales. The aim is to provide a plant drought monitoring product with farmland-specific services for water and socioeconomic management.

      Michael Triantafyllou is the Henry L. and Grace Doherty Professor in Ocean Science and Engineering in the Department of Mechanical Engineering. He is developing a web-based system for natural resources management that will deploy geospatial analysis, visualization, and reporting to better manage and facilitate aquaculture data.  By providing value to commercial fisheries’ permit holders who employ significant numbers of people and also to recreational shellfish permit holders who contribute to local economies, the project has attracted support from the Massachusetts Division of Marine Fisheries as well as a number of local resource management departments.

      Massachusetts shell fisheries generated roughly $339 million in 2020, accounting for 17 percent of U.S. East Coast production. Managing such a large industry is a time-consuming process, given there are thousands of acres of coastal areas grouped within over 800 classified shellfish growing areas. Extreme climate events present additional challenges. Triantafyllou’s research will help efforts to enforce environmental regulations, support habitat restoration efforts, and prevent shellfish-related food safety issues. More

    • 88 Shares179 Views

      in Energy

      Solar-powered desalination device wins MIT $100K competition

      by

      The winner of this year’s MIT $100K Entrepreneurship Competition is commercializing a new water desalination technology.

      Nona Desalination says it has developed a device capable of producing enough drinking water for 10 people at half the cost and with 1/10th the power of other water desalination devices. The device is roughly the size and weight of a case of bottled water and is powered by a small solar panel.

      “Our mission is to make portable desalination sustainable and easy,” said Nona CEO and MIT MBA candidate Bruce Crawford in the winning pitch, delivered to an audience in the Kresge Auditorium and online.

      The traditional approach for water desalination relies on a power-intensive process called reverse osmosis. In contrast, Nona uses a technology developed in MIT’s Research Laboratory of Electronics that removes salt and bacteria from seawater using an electrical current.

      “Because we can do all this at super low pressure, we don’t need the high-pressure pump [used in reverse osmosis], so we don’t need a lot of electricity,” says Crawford, who co-founded the company with MIT Research Scientist Junghyo Yoon. “Our device runs on less power than a cell phone charger.”

      The founders cited problems like tropical storms, drought, and infrastructure crises like the one in Flint, Michigan, to underscore that clean water access is not just a problem in developing countries. In Houston, after Hurricane Harvey caused catastrophic flooding in 2017, some residents were advised not to drink their tap water for months.

      The company has already developed a small prototype that produces clean drinking water. With its winnings, Nona will build more prototypes to give to early customers.

      The company plans to sell its first units to sailors before moving into the emergency preparedness space in the U.S., which it estimates to be a $5 billion industry. From there, it hopes to scale globally to help with disaster relief. The technology could also possibly be used for hydrogen production, oil and gas separation, and more.

      The MIT $100K is MIT’s largest entrepreneurship competition. It began in 1989 and is organized by students with support from the Martin Trust Center for MIT Entrepreneurship and the MIT Sloan School of Management. Each team must include at least one current MIT student.

      The second-place $25,000 prize went to Inclusive.ly, a company helping people and organizations create a more inclusive environment.

      The company uses conversational artificial intelligence and natural language processing to detect words and phrases that contain bias, and can measure the level of bias or inclusivity in communication.

      “We’re here to create a world where everyone feels invited to the conversation,” said MBA candidate Yeti Khim, who co-founded the company with fellow MBA candidates Joyce Chen and Priya Bhasin.

      Inclusive.ly can scan a range of communications and make suggestions for improvement. The algorithm can detect discrimination, microaggression, and condescension, and the founders say it analyzes language in a more nuanced way than tools like Grammarly.

      The company is currently developing a plugin for web browsers and is hoping to partner with large enterprise customers later this year. It will work with internal communications like emails as well as external communications like sales and marketing material.

      Inclusive.ly plans to sell to organizations on a subscription model and notes that diversity and inclusion is becoming a higher priority in many companies. Khim cited studies showing that lack of inclusion hinders employee productivity, retention, and recruiting.

      “We could all use a little bit of help to create the most inclusive version of ourselves,” Khim said.

      The third-place prize went to RTMicrofluidics, which is building at-home tests for a range of diseases including strep throat, tuberculosis, and mononucleosis. The test is able to detect a host of bacterial and viral pathogens in saliva and provide accurate test results in less than 30 minutes.

      The audience choice award went to Sparkle, which has developed a molecular dye technology that can illuminate tumors, making them easier to remove during surgery.

      This year’s $100K event was the culmination of a process that began last March, when 60 teams applied for the program. Out of that pool, 20 semifinalists were given additional mentoring and support before eight finalists were selected to pitch.

      The other finalist teams were:

      Astrahl, which is developing high resolution and affordable X-ray systems by integrating nanotechnologies with scintillators;

      Encreto Therapeutics, which is discovering medications to satiate appetite for people with obesity;

      Iridence, which has patented a biomaterial to replace minerals like mica as a way to make the beauty industry more sustainable; and

      Mantel, which is developing a liquid material for more efficient carbon removal that operates at high temperatures. More

    • 138 Shares129 Views

      in Energy

      Absent legislative victory, the president can still meet US climate goals

      by

      The most recent United Nations climate change report indicates that without significant action to mitigate global warming, the extent and magnitude of climate impacts — from floods to droughts to the spread of disease — could outpace the world’s ability to adapt to them. The latest effort to introduce meaningful climate legislation in the United States Congress, the Build Back Better bill, has stalled. The climate package in that bill — $555 billion in funding for climate resilience and clean energy — aims to reduce U.S. greenhouse gas emissions by about 50 percent below 2005 levels by 2030, the nation’s current Paris Agreement pledge. With prospects of passing a standalone climate package in the Senate far from assured, is there another pathway to fulfilling that pledge?

      Recent detailed legal analysis shows that there is at least one viable option for the United States to achieve the 2030 target without legislative action. Under Section 115 on International Air Pollution of the Clean Air Act, the U.S. Environmental Protection Agency (EPA) could assign emissions targets to the states that collectively meet the national goal. The president could simply issue an executive order to empower the EPA to do just that. But would that be prudent?

      A new study led by researchers at the MIT Joint Program on the Science and Policy of Global Change explores how, under a federally coordinated carbon dioxide emissions cap-and-trade program aligned with the U.S. Paris Agreement pledge and implemented through Section 115 of the Clean Air Act, the EPA might allocate emissions cuts among states. Recognizing that the Biden or any future administration considering this strategy would need to carefully weigh its benefits against its potential political risks, the study highlights the policy’s net economic benefits to the nation.

      The researchers calculate those net benefits by combining the estimated total cost of carbon dioxide emissions reduction under the policy with the corresponding estimated expenditures that would be avoided as a result of the policy’s implementation — expenditures on health care due to particulate air pollution, and on society at large due to climate impacts.

      Assessing three carbon dioxide emissions allocation strategies (each with legal precedent) for implementing Section 115 to return cap-and-trade program revenue to the states and distribute it to state residents on an equal per-capita basis, the study finds that at the national level, the economic net benefits are substantial, ranging from $70 to $150 billion in 2030. The results appear in the journal Environmental Research Letters.

      “Our findings not only show significant net gains to the U.S. economy under a national emissions policy implemented through the Clean Air Act’s Section 115,” says Mei Yuan, a research scientist at the MIT Joint Program and lead author of the study. “They also show the policy impact on consumer costs may differ across states depending on the choice of allocation strategy.”

      The national price on carbon needed to achieve the policy’s emissions target, as well as the policy’s ultimate cost to consumers, are substantially lower than those found in studies a decade earlier, although in line with other recent studies. The researchers speculate that this is largely due to ongoing expansion of ambitious state policies in the electricity sector and declining renewable energy costs. The policy is also progressive, consistent with earlier studies, in that equal lump-sum distribution of allowance revenue to state residents generally leads to net benefits to lower-income households. Regional disparities in consumer costs can be moderated by the allocation of allowances among states.

      State-by-state emissions estimates for the study are derived from MIT’s U.S. Regional Energy Policy model, with electricity sector detail of the Renewable Energy Development System model developed by the U.S. National Renewable Energy Laboratory; air quality benefits are estimated using U.S. EPA and other models; and the climate benefits estimate is based on the social cost of carbon, the U.S. federal government’s assessment of the economic damages that would result from emitting one additional ton of carbon dioxide into the atmosphere (currently $51/ton, adjusted for inflation). 

      “In addition to illustrating the economic, health, and climate benefits of a Section 115 implementation, our study underscores the advantages of a policy that imposes a uniform carbon price across all economic sectors,” says John Reilly, former co-director of the MIT Joint Program and a study co-author. “A national carbon price would serve as a major incentive for all sectors to decarbonize.” More