Would you exchange your steel and carbon fiber for a slab of lightweight dead tree?
Here's a fun lightweight material you probably never thought would be used for the purpose of weight savings in a car: wood. That's right, as in dead trees, those things that plastic trim strip on the inside of your 3 Series is supposed to mimic. Usually when it comes to wood and cars, the real stuff is fitted to luxury cars that don't have a care in the world about weight savings while the wannabe entry-level luxury vehicles get plastic colored to look like wood.
However, Japan Times claims that researchers on the island nation are looking into using wood for something other than interior decor. Namely, as a substitute for components that are much heavier, like steel. It might seem like a huge evolutionary step backwards to build crucial components out of wood, but researchers have a different trick up their sleeves. That would be breaking down the wood pulp fibers into small fragments that are several hundredths of a micron in size to make cellulose nanofibers. While that's going on, the fibers get kneaded into plastic to form a tough material that's about a fifth the weight of steel but five times as strong. This provides huge benefits over steel and other composites.
At current, a kilogram of cellulose nanofiber costs around $9.15. The lead researcher on the project, Professor Hiroaki Yano of Kyoto University, hopes that cost can be halved by 2030, which would make it competitive against steel (coming in around $2 per kilogram) because it gets combined with plastic to for the finished product. That drastically undercuts materials like carbon fiber, which costs around $100 per kilogram, though experts think our favorite use for the sixth element will drop to $10 per kilogram by 2025. Whether or not wood becomes a major component in automobiles of the future remains to be seen because there are still many hurdles to jump.
Even if the cellulose nanofiber manufacturing process is drastically refined, automakers would need to find a way to produce it on a mass scale and implement that into the modern automobile. Good luck with that.