Last week I wrote about Pringles cans and their more recyclable new design. The reason that Pringles cans were so notorious in the waste industry is that they are a hybrid that uses metal, plastic and cardboard. The materials can’t be separated and so they can’t be easily processed for recycling.
This is true of any complex product. Once you’ve mixed materials up, recycling is much harder. It isn’t necessarily impossible, but it requires more advanced techniques that in many cases just won’t be economical. The Pringles can is a relatively easy fix, but outside of the packaging world, simplifying material use is more complicated.
Take a typical trainer, or sneaker. Most of them will use a combination of plastics, rubber, leather and fabric. There may be synthetic fabrics such as polyester or nylon, and natural fibres like cotton or wool. There will be different types of plastic doing different jobs – soft foam padding, stiffer reinforcements and side panels, soles and treads. You might find a small amount of metal in the eyelets for the laces. Here’s a breakdown of a Nike shoe from the Shoemakers’ Academy if you want a detailed example.
That kind of complex build makes it difficult to recycle a shoe, and so most of them end up in landfill. There they will remain for the best part of a thousand years – we don’t know for sure, because plastics haven’t been around for long enough for us to tell. Of those are donated or handed in for recycling, much ends up on secondhand markets in the global south, or if poor quality, burned or landfilled there.
If you can get customers to send shoes back when they’re done with them, it is possible to make trainers that can be disassembled and processed. Usually this is down-cycling rather than recycling. Nike are a leader on this through their Nike Grind programme. Shredded trainers are turned into sports surfaces, carpet underlay, or rubbery chew toys for dogs. All good, but this ultimately only adds one more use before it ends up on the way to landfill again.
The solutions lie in a circular economy approach, where materials are taken back and genuinely reused. This is has so far proved very difficult, though there are some useful examples of progress. Several companies have developed concept shoes or are experimenting, with no commercial end product just yet. Salomon have gone further than most with their Index series of running shoes, which you can actually buy and wear. The Index O1 uses just two materials and is designed to be taken apart and ground down. Salomon designed a use for that recyclate in from the start, re-using it to make ski boots. (See below)
Decathlon went one better than Salomon this year with their pioneering hiking shoe the NH One. They took one of their popular designs, which is usually made with six different materials, and worked out how to make it with just one. It takes different forms, but the sole, the upper and the laces are all made of the same thing. The end result is a shoe that can be ground down altogether into raw materials, without the added expense of disassembly.
So far the NH One is a trial of just 3,000 pairs and only for sale in France, and Decathlon sell 3 million pairs of the non-recyclable version every year. Similarly, Salomon’s recyclable shoe is one option in a whole range of non-recyclable shoes. So even the best two examples are fairly limited so far. The only companies I’m aware of that are really putting circularity at the heart of their business model are start-ups, such as Hylo or Thousand Fell.
Still, it’s early days for circular economy footwear. Support those early efforts where you can.
The Earthbound Report 
Vivobarefoot is quite good at refurbishing their worn shoes. But they’ve also recently partnered with a company to find a circular solution for their footwear.