Mini has revealed an interesting fact about its limited-run Mini Cooper SE Convertible: It’s the first production car with wheels made from 100% recycled aluminum. Despite sharing the same look as wheels available on the regular SE hatch, they’re actually much more environmentally friendly.
The wheels were developed with Swiss wheel manufacturer Ronal. The company sells aftermarket wheels under the Ronal and Speedline brands, and it supplies OEMs. And it’s no stranger to more environmentally-friendly wheel production. It supplies wheels for the Audi E-Tron GT that are made using a smelting process that produces oxygen rather than carbon dioxide, and it now has a line of claimed carbon-neutral aftermarket wheels.
But back to the Mini’s wheels. Using all recycled aluminum has the obvious benefit of not requiring new aluminum to be manufactured. But the benefits are greater than just the raw material use. Mini points out that a major improvement in carbon emissions comes from being able to skip the electrolysis process for new aluminum manufacturing. Pure aluminum is extracted from aluminum oxide (which is in turn taken from the mineral bauxite). To do this large amounts of electricity are passed through molten solutions of aluminum oxide and cryolite (which takes energy to heat) across graphite cathodes and annodes. Not only does this use a lot of electricity that has its own carbon costs, the oxygen that separates from the aluminum bonds to the graphite annodes, yielding more carbon dioxide (which is why the production of those Audi wheels is also interesting).
In total, Mini says the recycled wheel production reduces carbon emissions by 75%. More specifically, it estimates about 0.16 kilograms (0.35 pounds) per kilogram (2.2 pounds) of aluminum used. Mini also stresses that this process still maintains all the strength of conventional wheels, just in a greener way. And of course, the wheels themselves are recyclable again. Mini, and BMW more broadly, are looking at ways to upscale the process and to source suitable recyclable products, likely other old wheels from cars no longer on the road. Though neither company said anything about when we’ll see fully recycled wheels more widely available.