From Treasure to Trash and Back
Embracing circular economies
By Dan Ferber
THE MOONSHOT: The rise of atmospheric dioxide, massive islands of waste plastic in the oceans, vanishing wildlife, and dwindling supplies of potable water are just a few of the signals that humanity is at an industrial inflection point. The game plan so far has been to extract raw materials, manufacture products out of them, and then — with a modest amount of recycling and repurposing — throw the products and the resources embodied in them away after the products are no longer directly useful. Now is the time to supplant this linear economic model with a more circular economy that acknowledges Earth’s finite resources. As in natural ecological systems, circular economies rely on complex networks of materials and energy sources in which the refuse of one sector of the system becomes the raw materials of another. Doing more and more, for more and more people, while consuming less and less is a moonshot challenge that humanity now has no choice but to embrace and realize.
THE PHILANTHROPY OPPORTUNITY: A planetary shift from a linear economic model to a circular one will require an all-hands-on-deck commitment. Governments on national and local levels and innovators in academe and the commercial sectors will all have to contribute to the cause. Moving to circular models of production and consumption will require myriad technological, political, infrastructural, and sociological changes innovations. Philanthropists can play pivotal and unique roles as well. For example, by infusing financial resources into circular-economy transformations, they can greatly accelerate shifts in sustainability in sectors ranging from manufacturing to food production, and from industries ranging from fashion to plastics. What’s more, they can do so without demanding near-term return on investment as the linear-to-circular economy transformations are initiated and take shape.
From the industrial revolution onward, the promise of progress seemed endless and resources seemed inexhaustible. Decade after decade, we scoured the planet for raw materials, and we converted those resources into thousands of products. Advances in technology and manufacturing, from the steam engine to mass manufacturing, and from Bessemer steel to a plethora of polymers, powered production. Coal and oil fueled economies of scale. More and more of the world became middle class, buying the cars, washing machines, televisions and toys that all that activity was producing. And when these products wore out, we did what was most convenient — we threw them away.
“We’ve been perfecting what’s effectively a linear economy for 150 years, where we take a material out of the ground, we make something out of it, and then ultimately that product gets thrown away,” says Dame Ellen MacArthur, founder of the Ellen MacArthur Foundation, which has led the drive for an alternative model. “It’s an economy that fundamentally can’t run in the long term.”
The reasons are simple: Resources are, in fact, exhaustible — and we are exhausting them. We’re depleting arable land, destroying forests, decimating fisheries, and burning nonrenewable fossil fuel. We’re accumulating 2 billion tons of waste each year worldwide. By 2030, we can expect 3 billion more people on the planet who will want a middle-class life. In a business-as-usual scenario, that will mean more consumption of resources, and a massive increase in waste and the environmental stresses that come with it.
MacArthur, a former sailboat racer who navigated solo around the world, had just returned to land in 2005 when this all hit her. To survive for the three months it took to sail around the world, MacArthur had to bring to sea absolutely everything she needed to live. “What we have out there is all we have,” she has said. “There is no more.”
When MacArthur finished her circumnavigation, she had an epiphany. Once we deplete the planet’s nonrenewable resources, that’s it. There is no more coal, no more oil, no more natural gas. There is no more indium-tin oxide, a key mineral used in flat-panel screens and touch-screen devices. There is no more neodymium, a rare-earth element essential for the neodymium-iron-boron magnets that large wind turbines use to generate electricity from wind. There is no more stibnite, the primary ore that supplies antimony, an important element for making flame-retardant materials. Without these and other often hard-to-obtain elements, and without fossil fuels, our manufacturing, high-tech, and military goods either would become unavailable or stop working. At a certain point, unless manufacturers find other sources of the materials they rely on, humanity’s ravenous appetite for the products of modernity will collide with Earth’s limited supplies, sparking shortages, supply chain disruptions, price hikes, even resource-driven conflicts. That prospect offers a sobering reality check that the dream of having everything we might ever want was a mirage.
“What we have out there is all we have. There is no more.” — Ellen MacArthur
If you know where to look, however, there are untapped goldmines out there. Rather than continuing to extract resources until there are no more left to economically obtain, we could look for inspiration to natural ecosystems, where frugality reigns, energy is renewable, and waste cycles back into resources. In economic terms, what’s waste to one part of the economy would become feedstock for another. Companies would use fewer resources, generate less waste, design goods that last — and, importantly, they would profit by doing so. When products finally wear out, they would be refurbished and reused. When that’s no longer possible, the products would be disassembled and their materials recycled. Waste and pollution would be designed out from the start.
In this model — which many know as the circular economy — existing products that have come to the end of their service lives become resources that can go head to head with the richest metal and mineral mines. Manufactured goods and products will drive a 21st-century supply chain of reusable parts and materials that will grow more valuable as the population increases and nonrenewable resources grow scarce. Businesses that embrace this circular approach to materials use will create new jobs, build flourishing industrial parks that live lightly on the land, and profit from conserving and regenerating resources.
In 2010 MacArthur launched the UK-based Ellen MacArthur Foundation to promote this vision, and the organization has become a leading force in driving the circular economy forward. In part, it’s succeeded by highlighting the tremendous benefits that are possible if a circular economy were deployed on national and global scales. With support from philanthropist Wendy Schmidt, the foundation started the New Plastics Economy initiative. This initiative brings together more than 400 businesses and governments behind a common vision of moving from a linear economy where materials are used and thrown away to a circular economy of reusing, recycling and repurposing plastic items.
By returning refurbishable equipment, worn parts, and usable materials to the economy, the World Economic Forum, in a report prepared in collaboration with the MacArthur Foundation, calculated that by 2050 a circular economy would reduce global demand for virgin material by 75% and the annual volume of landfilled waste by 68%.
Such dramatic reductions in mass production would reduce the rate of depletion of natural resources; it would allow biological resources like forests to regenerate; and it would mean less pollution of the soil, water, and air. Another prize here would be huge reductions in climate-disrupting carbon dioxide emissions. Applying circular economy strategies in just five key industries — cement, aluminum, steel, plastics and food — could eliminate the equivalent of 9.3 billion tons of CO2 emissions per year by 2050, according to a 2019 report from the foundation. This is 25% of our current global CO2 emissions, and is equivalent to eliminating all the emissions from today’s global transportation sector.
Equally important, companies would boost profits by employing circular business models that emphasize repeatedly leasing, renting or sharing products rather than selling them, as rental car companies and hotel chains currently do. This would provide incentives to make durable products that last, rather than planning for obsolescence. This in turn would pollute less, preserve resources, and take pressure off the Earth’s ecosystems, allowing them to regenerate. In other words, a circular economy operates by decoupling economic growth from resource consumption. That’s why a circular economy would unlock $4.5 trillion in economic growth by 2030, according to a 2015 report titled Waste to Wealth by Accenture, an international technology-centric consultancy.
Today’s economy is still a long way from circular: 91% of the fossil fuels, ores, minerals, and biomass that feed the global economy each year are still extracted from the planet, with just 9% of manufacturing resources deriving from previously produced materials, according to a report by the Circle Economy, an Amsterdam-based nongovernmental organization. Nonetheless, the idea of a circular global economy has gained momentum in the business world, with enterprises ranging from startups to multinational corporations adopting circular business models, and heavy hitters like the World Economic Forum and the U.S. Chamber of Commerce Foundation now promoting the model.
Governments have begun embracing circular-economy thinking as well. China, an early adopter, passed a law in 2008 mandating that new industrial policies must promote a circular economy. The country has built hundreds of eco-industrial parks modeled after a prototype in Denmark, where waste from of one industry or process becomes raw material or feedstock for others.
91% of the fossil fuels, ores, minerals, and biomass that feed into the global economy each year are still extracted from the earth, with just 9% of manufacturing resources deriving from previously made and used. — The Circle Economy
The European Commission, for its part, adopted an ambitious circular economy action plan in 2015 that in the 5 years since has produced a €10 billion investment in transitioning the region’s economy from linear to circular. The commission also adopted initiatives to modernize waste management systems, promote circular product design, and eliminate plastics pollution with an eye toward an overall transformation of the plastics industry from linear to circular frameworks.
Through such initiatives, and through technological and business innovations, a circular economy could potentially usher in a new industrial model that consumes and produces in almost equal measure with an elegance and frugality that evoke the zero-waste, natural world powered with renewable energy sources.
Trash as a resource
Before the circular economy becomes a planetary norm, more cities, states, regions and countries will have to find ways of implementing it. This shift is beginning, and circular models have begun sprouting in surprising places. As is often the case, in many of these locales, it’s a crisis that drives transformation.
Phoenix ran into one such crisis less than a decade ago. In the early 2010s, the city’s 1.5 million residents were generating more trash than ever. The city was picking up that trash from 400,000 single-family homes sprawled across 500 square miles of desert valley and trucking it to landfills 75 miles away. The garbage trucks drove 3.3 million miles annually, all the while consuming fuel and money. They dumped enough trash each year to fill Chase Field — the stadium where the city’s major-league baseball team, the Arizona Diamondbacks, play — to the brim. The city diverted only 16% of its solid waste from the landfill by reducing, reusing, recycling, or composting. That was less than half the national average of 34%.
The city’s low recycling rate was just part of its problems. In his 2011 book Bird on Fire, author Andrew Ross called Phoenix the world’s least sustainable city, because of its skyrocketing population, chronic water shortage, blazing summer temperatures, auto-centric transport, and air pollution. By 2013, Phoenix was eager to lose its reputation as an environmental bad boy, and so, among other steps, it needed to do something with all of its trash. The city’s former public works director, John Trujillo, and its mayor at the time, Greg Stanton, who now champions the region in the U.S. House of Representatives, set ambitious goals of diverting 40% of the city’s waste from the landfill by 2020, and 100% of it by 2040.
The two then pitched a plan to boost recycling as an economic development initiative to Phoenix’s conservative city council. “They said, ‘We’re going to take all this crap we’re burying, and turn it into jobs for the valley,’” recalls Rajesh Buch, a senior scientist at Arizona State University’s (ASU’s) Julie Ann Wrigley Global Institute of Sustainability. To figure out how to make profitable use of Phoenix’s trash, Trujillo and Stanton approached ASU, the powerhouse local university, located in nearby Tempe. ASU was by then known for its academic leadership in sustainability and entrepreneurship. “We wanted to create an incubator or accelerator for companies working on ways to profit from those materials,” says Brandie Barrett, Phoenix’s deputy public works director.
The resulting partnership, and Trujillo and Stanton’s municipal leadership, led to an ambitious initiative called Reimagine Phoenix, launched in 2013, that has more than doubled Phoenix’s waste diversion rate from its landfills. Through this initiative, in 2017 the city and ASU have created the nation’s first circular economy business accelerator, the Resource Innovations Solutions Network (RISN). Since then the RISN has nurtured 16 companies with circular business models. They have raised $3.9 million in capital, earned $4.1 million in revenue, filed patents, launched products, and created 74 jobs. The Ellen MacArthur Foundation has recognized this public-private partnership as innovative enough by ASU and the city of Phoenix to merit inclusion in the CE100, the foundation’s exclusive list of circular economy pioneers.
One of the companies RISN nurtured is Renewlogy, a Salt Lake City-based company that focuses on converting hard-to-recycle #3-#7 plastics — the types that rarely flow into municipal recycling systems — into chemical feedstocks to produce diesel fuel, solvents, and new plastics. Large industrial plants already existed that carry out this conversion through an industrial process known as pyrolysis, but they required more than $20 million of capital to build and 100 tons of plastic per day to operate. That feedstock requirement is far more than the 15 tons per day that even a mid-sized city like Phoenix could muster, says ASU’s Buch, who leads ASU’s circular economy activities. With support from RISN, Renewlogy founder Priyanka Bakaya and her team designed and tested an inexpensive industrial module that would annually consume 3,000 tons of otherwise landfill-bound #3-#7 plastics. The affordable module fits within a tennis-court-sized area, small enough to fit at most waste management facilities.
Renewlogy has yet to commission a plastics-to-fuel module in Phoenix or anywhere else, but in 2019 they tested their module successfully at their headquarters in Salt Lake City. They and a partner company, Sustane Technologies, will commission their first module in 2020 in Chester, Canada. Later, the company plans to install a module in Phoenix on 50 underused acres at a city-owned waste-transfer station that processes the city’s recyclables. That land will be home to the Resource Innovation Campus, a business accelerator that’s a joint venture between the city and RISN. There, companies will lease land from Phoenix at attractive rates, and use the city’s recyclable trash as raw material to convert into new, revenue-generating products.
Industrial symbiosis
Although trash may be plentiful, other resources are not, and when manufacturers’ hunger confronts supply shortages, pain is sure to follow. Robert Frosch saw that clearly more than 30 years ago, and to address the issue, he looked to nature for inspiration. Frosch, a physicist and then vice president of research at the General Motors Corporation Research Laboratory, was deeply immersed in the workings of the industrial economy. In a groundbreaking 1989 article in Scientific American, he and Nicholas Gallopoulos, the head of GM’s engine research department, explored how to make manufacturing more sustainable — and explained why it was imperative to do so.
By 2030, they predicted in their article, there would be shortages of critical materials, including copper, a key component of electric motors, and cobalt, molybdenum, and nickel — metals that go into key alloys used in aircraft engines, batteries, gas turbines, ship propellers and other important technologies. They also foresaw shortages of petroleum — the raw feedstock for fuels, asphalt, and a veritable catalog of chemicals. Enough solid waste would accumulate to bury Los Angeles under 100 meters of refuse, they predicted.
But if effluents from one industrial process — spent catalysts from petroleum refining, fly ash from electric-power generation, or discarded plastic containers from consumer products — could serve as the raw material for another industrial process, this would create a symbiosis that reduces both resource consumption and waste. Like the coral animals and algae that symbiotically make up a living coral reef, both industrial entities would depend on each other, and both would benefit.
Industrial symbiosis can work between two processes at a single company or between two companies. More complex arrangements reminiscent of a biological ecosystem are also possible, as illustrated by a pioneering industrial park in Kalundborg, Denmark. The Kalundborg Symbiosis, as it’s now called, took shape gradually, beginning in 1972, when an oil refinery began supplying excess refinery gas to fuel a wallboard manufacturing plant. At the same time, the refinery had already tapped a nearby lake for water, and when a coal-fired power plant at the park expanded, the refinery began shunting hot water from its cooling system to the power plant. The power plant fed the hot water, rather than room-temperature water, into its boilers to produce steam to drive turbines. That reduced fuel costs. The plant then shipped excess steam to a biotech company that produced insulin, which allowed the biotech company to shut down an inefficient boiler. When the power plant began scrubbing sulfur from its flue gas, the scrubbing process produced calcium sulfate, or gypsum, which it sold to the wallboard company, reducing that company’s need for freshly mined gypsum.
Over the decades, the Kalundborg Symbiosis has grown more complex. Today it is made up of six private companies and three public entities that exchange 25 different production streams, including water, steam for heating and energy, electric power, natural gas, fly ash, sand, as well as sugars, bioethanol, lignin (a major waste stream from papermaking), and fertilizer. In a 2015 life-cycle analysis, researchers compared Kalundborg’s greenhouse gas emissions to what they would be if the companies functioned independently; the symbiosis reduces CO2 emissions equivalent to what 40,000 Danes produce annually. The privately run industrial park, which employs more than 5,000 people, has been recognized by the Ellen MacArthur Foundation and many others as a leading example of industrial symbiosis.
Circular business models
To make global material and energy consumption sustainable, reusing trash and creating industrial symbioses are good starts. But until business leaders and decision-makers become confident that their companies can profit from cutting resource consumption and reducing waste, it will be difficult for the circular economy to scale. Fortunately, analysts and businesses are inventing new circular business models that can help build up that confidence, and forward-thinking companies are already putting these to profitable use.
Walter Stahel was one of the first to demonstrate that such a model could be profitable. Today he directs the Product Life Institute in Geneva, Switzerland, a nonprofit focused on sustainable strategies and policies for Europe. In 1973, Stahel was 27 years old, a trained architect, and already studying business strategy at the Battelle Geneva Research Centre. The Arab oil embargo was in full swing, and Europe, like the United States, was suffering from high oil prices. Meanwhile, unemployment had skyrocketed among Europe’s younger citizens.
Stahel was an environmentalist, and he began thinking about how to save energy while also creating jobs. “I knew that in building construction, if you refurbish or renovate a building, you need more labor and you save energy” compared with building a new structure, he told the Moonshot Catalog. Refurbishing or renovating a building saves energy by reusing the foundation and, if possible, the beams, posts, plumbing, and wiring. This preempts the consumption of energy to manufacture these building components from newly procured materials and products. And renovating a building takes labor, and thereby creates jobs. “I thought it might be the same in other sectors,” Stahel says.
If effluents from one industrial process — spent catalysts from petroleum refining, fly ash from electric-power generation, or discarded plastic containers from consumer products — could serve as the raw material for another industrial process, this would create a symbiosis that reduces both resource consumption and waste.
Stahel and a Battelle colleague, Geneviève-Mulvey, conducted a study showing that it was. The researchers examined decades of employment and energy use data from the automotive and building sectors. Producing the steel and cement used in these industrial sectors, for example, consumed three-fourths of the energy required to make completed cars and buildings, the analysts reported in 1977. The manufacturing and construction processes accounted for the final quarter of energy use — but these processes required three-fourths of the labor. This indicated that keeping processed materials in circulation, as opposed to producing them from virgin resources, should save energy and create jobs.
At first, critics said the economics of a circular manufacturing concept simply wouldn’t work, arguing that companies increase revenues by selling more products, and that once the product was sold and changed hands, there was no way for them to make more money. But Stahel persisted, and 5 years later wrote an influential paper proposing a new type of business model that suggests how companies can profit more by consuming less.
Rather than increasing revenue the typical way — by ramping up production and sales — a company could extend the service life of a product through reuse, repair, retrofits, or upgrades. They would then charge over and over to use the product, and profit even more than they would have by selling it. The beauty of such business models, Stahel realized, is that they eliminate any incentive for a company to design for planned obsolescence. Now at the Product Life Institute, Stahel continues to pursue this vision, arguing that it would create a more sustainable economy that would save energy, create jobs, and dramatically reduce waste. Today the model is a pillar of the circular economy, says Reid Lifset, an industrial ecologist at Yale University and editor-in-chief of the Journal of Industrial Ecology.
One early adopter of this strategy was Caterpillar, the heavy equipment manufacturer. Since 1980 the company has been buying back its worn-out engines and other equipment, and then refurbishing, remanufacturing, and reselling them. This saves the company the cost of obtaining the steel, aluminum, and other materials needed to build their large earth-moving machines from scratch. That, in turn, enables Caterpillar to charge customers less for the heavy equipment. This reduces operating costs for the construction firms, mining companies, and logging operations that buy that equipment. This, in turn, builds customer loyalty. Today 4,000 of Caterpillar’s 100,000 or so employees work on reclaiming and remanufacturing parts and products representing the equivalent of 75,000 tons of iron and steel each year.
In addition to improving their bottom lines by reclaiming, refurbishing, and remanufacturing, some companies profit by selling performance rather than their products themselves. Today, most manufacturers make their money selling the product as often as possible — a model that rewards planned obsolescence, which increases resource consumption and waste. Smart phone and electronics manufacturers, for example, offer upgrades that encourage customers to buy a new model every few years. While electronics can be recycled, many end up in dumps, especially in Asia, where they may leak toxic ingredients into the ground. In contrast, by reserving ownership and taking responsibility for maintenance and upgrades, a company can charge customers over and over to use the same long-lasting product.
This can create a financial incentive to make products last, which reduces the need for new manufacturing, thereby lowering resource and energy consumption and production costs overall. This producer-ownership model decouples economic growth from resource consumption. If adopted on a global scale, this model would greatly further the cause of sustainability.
Rolls-Royce, the world’s second largest maker of aircraft engines, has adopted such a model. The company offers customers the option of never buying its engines at all. Instead, the company charges for hours the engine is actually in the air. It also oversees engine maintenance, which reduces the chances that an engine malfunction will ground a plane and cost both Rolls-Royce and the airline money. Ninety-two percent of the airlines that get their engines from Rolls-Royce felt the new model had improved their business, according to a 2015 internal Rolls-Royce survey. “They’re really solving a customer problem,” says Aleyn Smith-Gillespie, coauthor of a recent report on Rolls-Royce’s circular economy programs and associate director of the Carbon Trust, a London-based NGO that promotes a low-carbon, sustainable economy.
By owning the engines it manufactures, Rolls Royce can simply take them back rather than buy them back when they wear out. This makes it easy for the company to reclaim parts. When it can’t refurbish those, Rolls Royce still recovers valuable materials, including 20,000 tons a year of the rhenium, hafnium, nickel, titanium, and other expensive metals. These materials, in turn, can fold back into production of the specialized alloys that high-performance aircraft engines require.
Circular or green?
As the circular economy has picked up adherents, a group of academics that call themselves industrial ecologists has been evaluating its potential benefits and shortcomings ever more rigorously. “Most of the proponents of the circular economy assume that if it’s circular, it’s green, and that this is self-evident,” says Yale’s Lifset. Instead, he says, it takes hard-hitting analyses to determine which circular business strategies actually reduce resource use and pollution and yield economic and social benefits.
Creating a common language for all stakeholders would be a start, since there’s no consensus on what a circular economy even means, says Jonathan Cullen, a lecturer in energy, transport, and urban infrastructure at Cambridge University and coauthor of the book Sustainable Materials Without the Hot Air: Making Buildings, Vehicles and Products Efficiently and with Less New Material, first published in 2015.
In the European Union, the circular economy movement is largely about reducing waste and using material resources efficiently, Cullen says. In China, it’s about industrial symbiosis, and the nation has built more than 150 Kalundborg-inspired eco-industrial parks. “It means different things in different parts of the world,” Cullen says.
There also are pitfalls that prevent a circular economy project from being truly green. Although recycling can save energy and resources, it doesn’t always. For example, “from an energy or carbon sense, it doesn’t make much sense to recycle concrete,” Cullen says. Production of cement (the mineral paste that holds sand, gravel, and stones together in concrete), requires heating limestone, clay, and other ingredients to 2700°F in a huge rotating kiln. That process consumes so much energy that it generates a full 8% of global CO2 emissions. It can take more cement to hold together the recycled concrete than it would to mix up a fresh batch from sand, gravel, and crushed stone, Cullen says.
To understand global resource use, it’s important to track each material as it flows through the economy. Scientists have gotten good at monitoring global and national energy consumption and carbon emissions. But materials are another story, Cullen says. “Globally we’ve got the International Energy Agency, but we don’t have the international materials agency,” Cullen says.
Materials-tracking data is scarce because it is difficult to track material flows through supply chains, between industries, and across borders, and because each of the hundreds of materials in the global economy would have to be tracked separately. To take on these gaps in knowledge and data, industrial ecologists have been developing material-flow analysis methods that researchers can use to monitor the input, output, and overall stocks of materials in, say, a factory, industrial park, or city.
So far, the industrial ecologists who conduct such analyses have labored in obscurity. But they say it’s time for industry and government stakeholders to embrace the mindset and toolsets they have to offer to help vet claims of environmental and economic benefits. “It’s time to take the circular economy to the next level,” Lifset says.
Enlarging the circle
Enough companies are pursuing promising circular strategies and verifying their commercial viability that investors are beginning to take an interest. One is Closed Loop Partners, a New York City-based impact investment firm that focuses on early-stage circular economy companies. It also runs the Center for the Circular Economy, which brings brands, NGOs, and startups together to support innovation in the field. “In the United States, we spend more than $10 billion each year to landfill what in a circular system could generate $15 billion in revenue,” says Kate Daly, the center’s managing director. “We look at waste as a design flaw.”
To scale up the circular economy, the field needs far more investment — angel investment, investment in early-stage companies, and growth investing, Daly says. “There’s a critical need for catalytic capital for early-stage support of emerging ideas to see who the winners are going to be.”
“In the United States, we spend more than $10 billion each year to landfill what in a circular system could generate $15 billion in revenue.” — Kate Daly
Such investment could fund innovations that a circular economy would require, such as breakthroughs in the logistics of reverse supply chains of the sort Caterpillar uses. In these chains, products return to their manufacturers for refurbishment, remanufacturing, or recycling. “That’s much more challenging than pushing products out,” Daly says.
For circular economy ambitions with no clear pathway to a finish line and no near-term business case, philanthropy could make important contributions, given its unique patience for return on investment (ROI) and the long-term view that it can bring to big challenges. “Philanthropy can be that lever by being a first mover in areas where capital is most needed,” says Stephanie Potter, senior director of the sustainability and circular economy program at The U.S. Chamber of Commerce Foundation.
Daly notes that applied research that facilitate materials recovery (such as robotics for sorting materials in a recycling facility in ways that yield more easily usable output streams or technology that turns discarded fabrics into fiber for new clothing) would also further the circular economy movement. Going even deeper, circular industrial ecologies would benefit from better technologies for deconstructing the highly complex materials that permeate the global economy into their constituent elements. For example, manufacturers rely on metal alloys — mixtures of two or more elemental metals — to make all sorts of industrial parts and commercial products. “The body of a modern car incorporates more than a dozen steel and aluminum alloys,” Stahel wrote in Nature in 2016. Reducing reliance on virgin ores would require unmaking these alloys to retrieve their constituent alloying elements, among them iron, manganese, nickel, and chromium. But there are few good processes to recover elemental metals from those alloys and doing so on much larger scales would require advances in metallurgy itself, Stahel writes.
A similar challenge confronts the chemicals and plastics industries, both of which are more in the business of making complex molecules and materials than in deconstructing them back to their constituent chemicals. Industrial ecology and green chemistry pioneers such as Paul Anastas of Yale University and John Warner of the Warner Babcock Institute for Green Chemistry have long lobbied for a cultural embrace by industry of design and production principles that ensure reusability, recyclability, and other resource-, energy-, and pollution-reduction benefits
To open the way toward a global deployment of circular economy practices, all stakeholders will need to participate. “We’ve got the attention, we’ve got the enthusiasm,” says Lifset. “Now let’s start grappling with the complications.” It will take a thousand strategies and a thousand initiatives to transform global economies from the current linear strategies to the circular ones all subsequent generations will need live by. But the time to act is now.
Dan Ferber is a science writer based in Jersey City, New Jersey.
