Circular Thinking

Humans are great at building things. We’re the best the world has ever seen. Heck, we start learning to build as children, piecing together toys on our bedroom floors.

Today, with specialized tools and components, we routinely build  sophisticated products — toasters, computers, automobiles … contraptions inconceivable to our distant ancestors. But our greats had us beat in one clear respect: They recycled and repaired as much as they could. We, on the other hand, are now producing more waste than the planet can process, and it threatens our health, environment and social stability.

From the materials we use to our manufacturing process, the modern supply chain is geared toward a linear economy: We produce new products and throw old ones away. But a new direction is gaining popularity, one in which our consumer waste becomes the feedstock of a circular economy.

Much of the modern world operates on a linear economy, which goes as follows: We extract minerals, oil, wood and other resources, which we process into materials like metals, plastics and paper. We take the materials and turn them into components, and then we turn components into products. Next, we sell; then we buy; then we use; and then finally, we discard.

“It seems to be an awful shame and a terrible waste,” says industrial ecologist Roland Geyer, “taking all of these raw materials, putting so much effort into turning them into very sophisticated things, and then using them only once.”

Even mattresses could be reused or recycled, Geyer says. He’s thinking way beyond packaging.

Turning natural resources into products requires a lot of time, money, energy and intention. “It’s not just the material; it’s all the value added, too,” says Geyer, a professor in the Bren School of Environmental Science & Management. “We lose all that value when we toss things out, rather than recycle. We have to make the next product from scratch.”


The linear economy is a relatively recent phenomenon. In earlier times, when things were harder and more expensive to make, there was incentive to reuse, repair or recycle goods. With mechanical production and mass consumerism developing in the 19th century, the linear supply chain soon prevailed. “By the mid-1950s and ’60s, the linear economy was solidified,” says historian and professor Erika Rappaport, who studies the history of consumption and commodities in the 19th and 20th centuries.

Many countries built up their manufacturing capacity and were producing, or overproducing, supplies for World War II. When the war ended, there was an oversupply of products in need of new consumers.

“Meanwhile, people were desperate to get new things,” Rappaport says. Society was emerging from some 16 years of depression and wartime austerity. Work hours had expanded and more women were in the workforce, further driving the demand for labor-saving devices. Convenience was king.

“The goal was more, faster, cheaper,” Geyer says, so we restructured our supply chain and expanded production, “and this incredible scaling of mass production is a lot easier in a linear economy.”

Meeting current supply demands in a circular economy will require a big pivot for people and industries alike. To be truly circular, we’d need to make some fundamental changes to the things we use, choose and produce, and globally redefine our manufacturing ethos.


Turns out, for as good as we are at building things, we’re not that great at taking them apart.

“We design products for optimum performance at minimal cost, but we don’t design them to be recycled,” says Distinguished Professor Susannah Scott, whose research lies at the intersection of chemistry and sustainability. “That will require changes in the way that we think about materials.”

Complex, multilayer packages work very well — think chip bags and padded envelopes — but they are exceedingly difficult to disassemble and recycle. So, they end up in the bin, and then the landfill. Eventually, these materials will break down and turn back into crude oil, but that takes geologic timespans. In the meantime, they choke our planet and waste our time, money and resources.

Big chemical companies have started to recover some materials, liquefying them at high temperatures and blending them into the oil refining process. But this is inefficient and has limited use, explains Scott, the Mellichamp Chair in Sustainable Catalysis.

The next step is designing products that can be disassembled into their components, and designing components that can be broken down into their molecular makeup. Time, use and processing all degrade materials. The utility of plastics drops precipitously after recycling. Additives, adhesives and so forth get mixed into the reclaimed material and the result is appropriate for only the most basic of products, like rugs and composite lumber.

“Even if you had absolutely pure polymer, those molecular chains degrade when you reprocess them,” Scott adds. Materials like plastics are highly engineered. Polymer lengths, structure and composition are all tightly controlled to produce specific properties. All of this optimization is lost when plastics are blended together during recycling.


By reducing materials to their molecular components, we can produce recycled materials with the same properties as their virgin counterparts. Indeed, Scott’s group works on disassembling polymers — specifically polyethylene and polypropylene — into ingredients that can be returned to the supply chain. She’s even found processes where beginning with the recycled plastic is more efficient than starting from crude oil.

Technology alone won’t solve this issue, but it will be critical to our solution. “We need people to reimagine how we make things and how we use them,” Scott says, “but we also need changes in behavior.”

As long as resources are cheap, people will continue producing virgin materials. The standard argument is that circular practices are currently too expensive to compete with a linear supply chain.

“But this is thinking the wrong way around,” Geyer says. “It’s not that reuse and recycling is too expensive; it’s that virgin production is too cheap.”

Not only has society designed the modern supply chain around virgin production, but the prices of products reflect the true cost of these practices. Economists call these indirect impacts “externalities,” and the linear economy is rife with them.

Ironically, Geyer suggests that we shouldn’t focus on incentivizing circular practices. Rather, we need to disincentivize linear practices. You might think this is the same thing, but evidence suggests it isn’t. For instance, instead of discouraging the use of fossil fuels, a lot of governments are promoting renewable energy. “But this could mean that we’re just going to do it all,” Geyer says: “keep our fossil fuels and use a lot of renewable energy as well.”

Similarly, if recycling becomes cheap, we may just use it alongside virgin material. “The green revolution has been a double-edged sword,” he says. “It basically allowed us to not talk about limits and just expand.”

To do less harm, we need to curb our worst practices, not promote our best ones, Geyer argues. Ultimately, this means producing less overall.

Rappaport’s historical perspective leads her to a similar conclusion. Consumption is inexorably linked to people’s working lives. As specialization and work hours expanded, people were left with less time, energy and skills to reduce, repair and recycle. “You have to slow things down,” she says.

“Overall, there’s no one strategy that’s going to solve the whole problem,” Scott adds. “But I think the world is ready to start thinking about this in ways that we weren’t even five years ago.”

Fall / Winter 2022


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