It sounds simple. But a study published in 1998 by the Society of Automotive Engineers found that midsize American sedans comprised about 20,000 components. Cars have only gotten more complex, which is a challenge for recyclers, said Greg Keoleian, lead author of the study, now a professor at the University of Michigan’s Center for Sustainable Systems. “There’s a lot of room for improvement at end of life of the vehicle,” Mr. Keoleian said.
Car recyclers strip valuable parts, like working engines, for reuse. The remaining hulks go to scrap metal companies, which typically shred the rest. But the mixed alloy shred has limited use.
Take aluminum. “The aluminum stream in that case is a mix of a lot of different alloys, including cast alloy, which doesn’t go well back into sheet,” which is used in body panels, said John Weritz, vice president of standards and technology at the Aluminum Association. The demand for unmixed material is growing as carmakers increasingly use lightweight aluminum body panels, he said.
In circular manufacturing, the answer to the sorting problem is to change the design process to include a plan for dismantling, so a retired car is easy to separate into like sources of metal, plastic, rubber and glass. Setting cars up to provide easily recycled materials helps free manufacturers from supply chain issues: The car becomes its own supply chain.
One place the car industry says it is making tangible gains is in packing and shipping materials. “We reduced packaging by using reusable shipping containers,” said Kevin Butt, chairman of the Suppliers Partnership for the Environment, a consortium of companies and government agencies that deal with transportation. Although the idea isn’t new, Toyota North America, where Mr. Butt is director of environmental sustainability, said that since 2017 it has reduced 65 million pounds of cardboard and 171 million pounds of wooden crates, and has saved $273 million by using containers molded of recycled plastic to ship parts like struts, catalytic converters and steering wheel shafts. The consortium wants to see the practice adopted by all of its members.
Between building and recycling there is, of course, use. The circular goal there is to extend how long a car remains on the road: Fewer new cars mean fewer materials and less energy needed to build a new one. But there is a hitch — at a certain point keeping an aged car running may contribute more to pollution than building a new one would.