What is a car made of? Even a child could tell you: mostly metal, plastic and some rubber here and there, right? Well, there’s more to it than that. Particularly if the car is a Lexus.
When it comes to engineering amazing, the Japanese carmaker isn’t just referring to perfectly tuned engines or beautifully contoured bodies. It is also describing the processes that turn sweet potatoes, sugarcane, soybeans and corn into a car that’s not only amazing to to drive, but just about good enough to eat.
The finest ingredients
As with any recipe, the first step is to have the finest ingredients. Castor seed oil and soy are used to make seat cushion foam for many Lexus models, with excess foam used for soundproofing in other parts of the car. The fibre of the kenaf, a member of the hibiscus family, is a useful ingredient in car door trims.
Bamboo beats
The Lexus GS 450h has an optional laminated bamboo finish for an extra touch of style, but the plant doesn’t just make a Lexus look great; it can make it sound amazing too. In the Lexus CT, bamboo fibres are used for the speaker diaphragms – delivering clearer, higher-performing sound reproduction, lowering the overall weight of the car and, perhaps most importantly, being more environmentally friendly.
Material impact
All of this might seem bizarre, but using natural and sustainable materials, rather than ones derived from fossil fuels, is a vital part of carmaking for any manufacturer worth its stripes. That is not a goal that ends with making a car more fuel-efficient, or launching a hybrid, like the Lexus CT. It is also about the environmental impact of the car factory and what happens to the car at the end of its life.
Making cars recyclable
Lexus aims to make its cars 95% recyclable, which is why it has been reconsidering the materials used in building a luxury car. Curiously enough, that means exploring the kind of ingredients you might find in your larder. Plastics are an important component in any modern car, but conventional ones are produced from petroleum and so, by definition, not environmentally friendly. So Lexus has developed new, biodegradable plastics to take their place.
A new kind of plastic
There are different kinds of plastics, with different performance characteristics, that are recyclable to varying extents. One example is PET, a common plastic used to make water bottles. It is a useful material, but made from non-renewable fossil fuels. So Lexus created a new plastic, that it calls bio-PET, to take its place. Made with sugarcane, bio-PET is not only biodegradable but also easily renewable. This new plastic makes up around a third of the plastics used in the Lexus CT, reducing the vehicle’s carbon footprint.
Sweet potato and corn
Another advanced material helping to make Lexus vehicles eco-friendly is PLA, produced from the fermentation of corn starch. PLA can be produced with 65% less energy than conventional plastics. Then there is the humble sweet potato, another starch, used to make the interior plastic on models such as the Lexus RX.
Carbon negative
An added benefit of these materials is that the plants used to make them absorb carbon from the atmosphere while they grow, so some parts of the process become “carbon negative”, removing more carbon from the atmosphere than is released by their manufacture and use. It’s even possible that, rather than being recycled, some of these materials could be burned as a fuel source.
Engineering amazing
One of Lexus’s goals is to develop materials that can be used on the car’s exterior. This is a huge challenge, because the outside of the car is exposed to all types of weather, meaning these materials have to be able to withstand heat, light and moisture. Even so, it won’t be long before, as you stop at the supermarket to pick up some sugar and sweet potatoes, you’ll be parking up in a Lexus carefully crafted from those same items.
