Sustainability In Your Ear

Each year, over 11 million metric tons of plastic end up in the ocean, which is like dumping a garbage truck full of plastic every minute. For years, we’ve known that marine animals eat this debris, but no one had measured exactly how much plastic it takes to kill them. Dr. Erin Murphy, who leads ocean plastics research at the Ocean Conservancy, is the principal author of a major study published in the Proceedings of the National Academy of Sciences. Her team analyzed more than 10,000 necropsies from 95 species of seabirds, sea turtles, and marine mammals worldwide. Earth911’s summary describes this critical study, which found lethal plastic thresholds that could change how we view the plastic crisis.

The study measured how deadly different types of plastic are to sea life, which makes the results especially useful for policymakers. Each finding suggests a clear policy action, such as banning balloon releases like Florida has done, banning plastic bags as in California’s SB 54, or improving how fishing gear is marked and recovered. Still, Erin points out that focusing only on certain plastics is not enough. Her team found that even small amounts of any plastic can be dangerous. As she says, "At the end of the day, there is too much plastic in the ocean," and we need big changes at every stage of the plastics life cycle, from production to disposal.

There's encouraging evidence that interventions work. Communities in Hawaii conducted large-scale beach cleanups and saw the Hawaiian monk seal population rebound. A study published in Science confirmed that bag bans reduce plastic on beaches by 25 to 47%. And Ocean Conservancy's International Coastal Cleanup, now in its 40th year, removed more than a million plastic bags from beaches last year. These actions address a parallel crisis in human health that is building from the same pollution source. Most of the microplastics now found in humans and around the world began as the same macroplastics that are killing puffins and turtles. As Erin puts it, "I do view this all as part of the same crisis."

You can read the full study at pnas.org and learn more about Ocean Conservancy's work at oceanconservancy.org.

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Every gallon of wastewater flowing through a municipal sewer contains recoverable energy, nutrients, and water—assets that the linear "flush and forget" model has long treated as problems to dispose of rather than value to recapture. Meet Kevin Shafer, who has spent more than two decades proving otherwise. As executive director of the Milwaukee Metropolitan Sewerage District (MMSD) since 2002, he's transformed an agency once mocked as a symbol of government waste into a national model for sustainable infrastructure, and last year, Veolia designated it as America's first "eco factory."
 
Milwaukee's circular approach actually predates the term by nearly a century. In 1926, the district began producing Milorganite—Milwaukee organic nitrogen—a fertilizer made from dried biosolids that most utilities simply spread on fields or incinerate. Today, that product returns $11 to $12 million annually to the city's budget while keeping waste out of landfills. Kevin explains that this foundational commitment to doing the right thing has shaped MMSD's culture ever since: 'We just always look at those type of approaches. It's foundational to the district.'

The district's eight digesters at its South Shore plant now generate 80 to 85% of the facility's electricity from biosolids, with enough material left over to continue making Milorganite. Kevin calls it Cradle to Cradle in action, referring to the philosophy pioneered by architect William McDonough, who visited MMSD in 2006 and was intrigued by work that predated his framework by decades. The district is also partnering with regional breweries and food processors, accepting their organic waste streams for co-digestion. This reduces disposal costs for industry partners while increasing energy production—a synergy that Kevin sees as the future of utility operations.

Looking ahead, Kevin's 2035 vision targets 100% renewable energy and a 90% carbon reduction compared to 2005. He argues that utilities should see themselves as anchor institutions with generational responsibilities: 'I won't be here 50 years from now, but MMSD will be.' That long view has attracted new partners. 'All of a sudden they say, oh, here's someone that's thinking a little bit differently about something, and maybe we can help them, or they can help us.' The key barrier to scaling the circular economy, he believes, isn't technology—it's institutional culture and a narrow focus on regulatory compliance rather than systems thinking.

You can learn more about the Milwaukee Metropolitan Sewerage District at mmsd.com.
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Global investment in the energy transition reached $2.2 trillion in 2025, up 5% from the previous year despite political headwinds intensified. Peter Fusaro has watched this market evolve from a niche curiosity into a systemic financial concern. As founder of the Wall Street Green Summit, he's spent a quarter century connecting capital to climate solutions. This year's summit, the 25th in its history, will take place on March 10 and 11 in New York. This critical conversation arrives at an historic inflection point: insurance companies are withdrawing from climate-vulnerable states, AI data centers are straining electrical grids, and the economics of clean energy have fundamentally shifted.

The energy transition's bottleneck isn't capital, it's infrastructure. The U.S. went from 110 investor-owned utilities in 1992 to just 40 today, and consolidation meant underinvestment in transmission and distribution. Data centers consumed 2% of U.S. energy demand in 2020; Peter sees that climbing to 10-12% by 2030. Blackouts and brownouts are inevitable, he says. Yet his message is pragmatic optimism: ignore Washington and watch the capital markets and blue states where climate policy is embedded in law. Many companies are "green hushing," quietly pursuing sustainability without public positioning. The energy industry thinks in 40-year cycles, making the current political moment a blip. "I've spent 56 years now in sustainability, before it had a name," he says. "What I've learned is change takes decades."

Peter argues that Wall Street has genuinely internalized climate as systemic risk—not because of ideology, but because of opportunity. "Wall Street likes exchanges, likes to trade, likes volatility, and certainly likes uncertainty," he explains. "What people don't understand about Wall Street, it's about the edge. What's the arbitrage opportunity?" The reinsurance industry has stepped forward aggressively, funding carbon credits and sustainability projects. Peter's recent Earth911 article, "Climate Risk Has Become a Defining Economic Issue," explores these themes in depth.

However, he sees natural gas and renewables dominating the next 15 years, while geothermal is enjoying a genuine renaissance. His optimism rests on a demographic bet: "I have a tremendous valuation on young people. I'm 75. They're inheriting this world, and they get the sustainability message globally." The summit attendees includes no government officials and no academics, just people in the trenches building and financing solutions.

You can learn more at TheWallStreetGreenSummit.com. Earth911 is a media sponsor for the event.
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What we call waste is really just misallocated feedstock—raw materials waiting to be cycled back into the next generation of products and packaging. According to research by the World Economic Forum and United Nations Development Programme, the circular economy could unlock $4.5 trillion in new global value by 2030, and investors are racing to capture part of that opportunity. Meet Elizabeth Blankenship-Singh, Director of Innovation at Overlay Capital, an Atlanta-based alternative investment firm whose Waste and Materials Fund is backing both early-stage materials innovators and later-stage recycling operations with established infrastructure. Overlay's strategy involves investing in innovation and implementation simultaneously—in both startups and established companies—to accelerate progress across multiple layers of the circular economy. It offers a window into where smart money sees the materials transition heading.
 
Elizabeth explains that sortation is the biggest bottleneck at the materials recycling facilities (MRFs) your garbage and recycling are sent to after curbside collection. The U.S. is simultaneously the world’s leading exporter of scrap aluminum and the number one importer of finished aluminum, because we've lacked domestic sorting capacity. Overlay has invested in companies like AMP Robotics, which recently closed a 20-year contract with SPSA, a southeastern Virginia municipal authority, to sort all recyclables from four to five cities using AI-driven systems. When you fix sortation, she says, you trigger a domino effect: recycling rates climb, landfill life extends, and margins improve as higher-purity materials command premium prices.
 
Overlay's portfolio also includes next-generation materials companies united by a common thesis: they must be better, faster, cheaper, and more sustainable than what they replace. Cruz Foam converts chitin from shrimp shells into compostable packaging foam. Simplifyber uses cellulose to create biodegradable soft goods through 3D molding, bypassing traditional textile manufacturing entirely. Terra CO2 just closed a $124 million Series B to scale low-carbon cement technology that could cut into concrete's 8% share of annual global CO2 emissions. Each uses abundant, waste-derived feedstocks and has achieved or is on a clear path to price parity with incumbents.

You can learn more about Overlay Capital at overlaycapital.com
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Amazingly, the same Congressional bill that gutted residential clean energy tax credits also led to a major breakthrough in financing home geothermal systems. Dan Yates, CEO of Dandelion Energy, explains how the Big, Beautiful Bill introduced changes that, for the first time, allow third-party leasing of residential geothermal systems. He shares why this policy change could help ground-source heat pumps grow the way leasing helped rooftop solar. Geothermal heating and cooling is four times more efficient than a furnace and twice as efficient as air-source heat pumps. Yet only about 1% of U.S. homes use it because the upfront costs for new geothermal systems have ranged from $20,000 to $31,000. The new leasing model means new homeowners can get geothermal systems for just $10 to $40 per month on a 20-year lease, which is usually far less than what they save on energy.
 
Dandelion is working with Lennar, one of the largest homebuilders in the country, to bring geothermal to more than 1,500 homes in Colorado over the next two years. This will be one of the biggest residential geothermal projects in U.S. history. The benefits for the power grid could be even more important than the savings for homeowners. Geothermal systems use only 25% of the peak power that air-source heat pumps need, which is a big advantage as AI data centers increase electricity demand. Yates explains that the Earth works like a huge thermal battery, storing heat in the summer for use in the winter. Geothermal lets utilities reduce peak loads on the grid throughout the year, freeing homeowners from the cost of the most expensive power.
 
You can learn more about Dandelion Energy at dandelionenergy.com.
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