This article was adapted from Bright Green Future, a book that chronicles a global renaissance in people-powered solutions to climate change.
When we fixate solely on cutting out waste, the outlook for the environment can be discouraging. It seems we’ll need a million campaigns to save our planet from discarded items as simple as plastic straws to those as complex as lithium-ion batteries. If we look closer though, we find that ecosystems themselves hold the key to their own preservation. When we learn from the way nutrients are constantly broken down and repurposed in natural systems, we find opportunities for a circular economy everywhere.
A hero in the mud
Bubbling in natural geysers all over the world—such as the hot mud of Old Faithful—there’s a creature that’s made a home for itself. It’s a bacteria called Methylocystis parvus, and it feeds on the methane released from plants decaying in slow motion. For over 200 million years, these organisms have evolved in a microscopic ecosystem where the main energy source is a gas.
Dr. Allison Pieja spent years in the labs at Stanford studying how these bacteria work. She published extensively on how they use methane to build long chains of complex polymers. It was during her PhD studies that she met Dr. Molly Morris, who was working on sustainable materials for the construction industry. “It turns out that Molly’s work needed Allison’s work, and Allison’s work needed Molly’s work,” said Dr. Anne Schauer-Gimenez, who would later join their team.
When you picture startups in the San Francisco Bay Area, you might think of a hip coworking space with cold-brew coffee on tap and walls plastered with inspirational quotes by Steve Jobs. The office of Mango Materials is a little different.
The road reached a dead-end at the Redwood City wastewater treatment plant and the smell was as you might expect. Anne welcomed me through the gates. We put on hard hats and walked down a set of stairs, following a network of metal pipes to an outdoor expanse of giant concrete drums. They were biodigesters that used bacteria to break down waste into a form that doesn’t make us sick. Another set of pipes connected one of the digesters to a much smaller ten-foot-tall cylindrical chamber. This, I was told, is where the magic happens.
Methane from the digester enters the chamber where it feeds a colony of hungry bacteria. At first, they start dividing like crazy. Their numbers surge as they colonize this new habitat. Then, with a few twists of the knobs, they’re cut off from their food source. They go into survival mode, building up an energy reserve for later. This energy reserve is made from the exact compound of an extremely versatile biopolymer, an ideal building block for a wide range of plastics. The Mango team then harvests the crop of microbes, leaving a seed group behind for the next batch. From the microbes, they extract a fine white powder, which they pelletize and then inject into plastic molds.
The plastic that comes out is different from plastic as we know it. Because it’s a naturally occurring substance, it’s easily broken down. Where most compostable plastic on the market has to be processed in industrial-scale composting facilities, these polymers can biodegrade in the yard. “We’ve done some very unscientific studies in our CEO’s home compost,” said Anne. More importantly, this polymer can decompose in the ocean. If an animal happens to eat it, they’re able to digest it.
There are also many more applications for these polymers than for most of the existing biodegradable plastic on the market. The bacteria can produce over 100 different monomers—the building blocks of plastic polymers—allowing for plastics of many forms from casings for electronics to plastic bottles.
Their technology creates a new way to look at recycling altogether. Even if your bio-plastic bottle were to end up in the landfill—if that landfill were connected to one of Mango’s systems—it would decompose back into methane. There, it could be captured and transformed back into another plastic bottle. It’s essentially a biological recycling system that could help us reconceive landfills as not the end of the line for our products, but the beginning. Sites not for waste, but for value creation.
Mango envisions a new approach to infrastructure that is significantly less capital-intensive. Rather than establish massive plastic factories, Mango wants to license mobile modules that can plug into any source of methane and start producing immediately. Imagine if every city had its own source of extremely versatile materials made from the sweet nectar of benevolent bacteria. It’s a rose-colored dream compared to relying on the concentrated byproducts of petrochemicals that are shipped across plastic-choked seas.
Mango uses biology to re-envision the way we make things. It’s what’s called a “biocycle.” But not all industrial systems that copy the way nature regenerates materials have to use biology. There’s another cycle that uses artificial means to do what natural nutrient cycles do so well. It’s been dubbed the “technocycle” by architect William McDonough and chemist Michael Braungart, the authors of Cradle-to-Cradle, who helped popularize a vision for circular industry. The “technocycle” includes basically all manufactured products that can’t be broken down by nature. These materials are persistent and often toxic, like heavy metals. When they do end up in nature, they’re what we call pollution.
It’s possible, though, to find ways of safely breaking them down. Rather than letting them destroy our environment, we can keep them in circulation, where they create value rather than destruction. For a glimpse of what that might look like, we now turn to the fastest-growing waste stream on the planet.
Darkside of Moore’s Law
While shiny and sleek on the front end, our tech industry has created a monster on the back end. Each new gadget kicks millions of older models into obsolescence. Discarded electronics get shipped by the crateload to the developing world, where their toxic components can poison entire neighborhoods. In Bangladesh, children dip circuit boards into open vats of acid to get at the copper and gold nested inside. In the Congo, warlords use slave labor to mine the cobalt that supplies the world’s battery manufacturing.
After watching the documentary Ghana: Digital Dumping Ground, Peter Holgate saw how his career in tech might be contributing to the darkside of Moore’s Law. He became inspired, not to create the newest gadget, but to figure out what to do with those gadgets when they’re disrupted by the next big thing.
Rather than try to invent a new technology from scratch, he suspected that the tools to address the problem might already be out there. He stumbled across a strange piece of equipment built for an entirely different purpose. At the time, it was languishing in the tent of an environmental remediation company. It was a machine made up of a 13-foot-long steel bar surrounded by electromagnets. It’s “basically a massive tuning fork,” originally built to “literally shake the gold out of mine tailings using sound energy.”
Harmony in the machine
This sonic machine is extraordinarily efficient at separating materials, especially when compared to smelting—the main method for recovering metals from our discarded electronics. Traditional recycling uses an arc plasma furnace to melt everything down, which requires a tremendous amount of power, often generated by burning coal. By contrast, the tuning fork technology separates the mélange of materials in a circuit board by using what’s known as “harmonic resonance.”
“When you go ‘ping,’ the tuning fork is humming and you just add a touch of energy, just to keep it at that rhythm and state, a harmonic state.” From this technology, Peter and his partners founded Ronin8, a company focused on creating a circular life for electronic devices.
At their facility, old laptops, monitors, and cell phones enter the process whole. They’re shredded under water to prevent toxic dust from escaping into the air. These minced bits of e-waste are then fed into the machine, which fine-tunes its pitch to separate each material based on its specific density. First the non-metals are released. Finally, one by one, each metal resonates with its perfect harmony.
Cornucopia of metals
“We’ve found up to 21 different metals in most electronics. It’s like the entire periodic table. Even the guys who are recovering the primary metals—you know, gold, copper, silver, platinum, palladium—are ignoring most of the rarest elements, like promethium and tungsten,” said Peter. “We started down the path of being able to recover all of them.” Currently, mining these rare-earth metals requires an intensive chemical process to liberate them from the dirt. Often they’re bound up with radioactive byproducts like thorium, all of which end up seeping into the groundwater.
The current smelting process to recycle metals isn’t able to recover these rare earth elements. In addition, it requires high levels of energy and emits toxic particles. “You create dioxins, which are the same thing you find in DDT and Agent Orange.” The two main ingredients in Ronin8’s process are sound and water. After the discarded electronic components have been separated, the remaining particles are filtered through a fine sieve and the water is reused indefinitely.
Peter hinted that the process might be well suited for recycling solar panels. “The entire solar panel industry is staring down at a legacy issue without the means to solve it,” he said. “The solar panels that were built 15 to 20 years ago are all aged out and need to be taken down. These work incredibly well in our sonic system.” Ronin8 is currently perfecting their technology to safely and affordably recycle lithium batteries. This could help address the looming specter of the millions of used electric car batteries that the world will come to generate every year.
The company also wants to provide an opportunity for people in the developing world who live where this waste falls through the cracks. They envision their technology being able to fit into a shipping container. “Instead of having some kid melt away the plastic to get at the copper, you have a simple, easy way to separate the two.” It could give people living anywhere in the world the means to safely transform complex waste into a cornucopia of useful materials.
In nature, leaves and branches fall into streams and end up far away from their places of origin. But they don’t pollute their new environments. Natural systems are adept at converting leaf litter into food, fertility, and new life. In our modern economy, we’re not talking about branches and leaves, but circuit boards and copper wires. The material may be different, but our approach and intention when dealing with them should model nature’s. Our goal should be to allow anyone, wherever they are, the opportunity to create value from the problem formerly known as pollution.
We’ve spent the last 100 years perfecting the assembly line. It’s now time to perfect the disassembly line. Nature is able to take extremely complex structures and break them down into the pieces needed for the next generation. For everything we create, we need an efficient solution to break it down and cycle it back into the pieces from which it came. In doing so, we can create value out of nothing, protect the environment from toxic chemicals, and avoid depleting our precious natural resources.
For more stories like this, check out Trevor’s new book, Bright Green Future.