Car makers need to be green as well as lean to survive. That means more than just having all-electric cars in their model line-up. It means, increasingly, using recycled materials to build their products.
Manufacturers have been experimenting with new techniques for using aluminium, carbon-fibre and plastic in their vehicles, while the use of other post-consumer materials has also crept up – from Cadillac's use of old tyres to Audi's of scrap cotton.
The car industry is used to recycling steel from scrapped vehicles – about a quarter of the steel in conventional cars has been recycled. But it has recently been looking for lighter alternatives – especially for electric cars, which have to bear the weight of heavy batteries.
Car makers such as Jaguar Land Rover (JLR) and Audi are increasingly using recycled aluminium for the structures of their vehicles. BMW, meanwhile, is using carbon-fibre reinforced plastic, which is lighter still, for electric and hybrid vehicles such as the i3 and the i8.
Recycling aluminium is more of a headache than recycling steel, but there is a big incentive to do so. Smelting the material in the first place is extremely energy intensive – one reason why aluminium is expensive.
Pioneering project
Premium vehicle manufacturer JLR is taking control of this process with its pioneering Reality project, aimed at “closed-loop” recycling of aluminium from end-of-life vehicles. It uses hi-tech techniques to sort the aluminium before melting it down and reusing it, saving on both cost and carbon dioxide emissions in the manufacturing process.
The Jaguar XE was the first vehicle in the world to have body panels made from RC5754-grade aluminium alloy, which contains up to 75 per cent recycled aluminium. Half the XE body structure is made of aluminium alloy grades that incorporate a significant amount of recycled metal.
“More than a million cars are crushed every year in the UK and this pioneering project affords us a real opportunity to give some of them a second life,” says Gaëlle Guillaume, lead project manager for the Reality project at JLR. “Aluminium is a valuable material and a key component in our manufacturing process and as such we're committed to ensuring our use of it is as responsible as possible.”
Fibre options
As for carbon-fibre components, these achieve high levels of rigidity combined with low weight by using long strands of the fibres held together with resin. But making them has in the past been labour-intensive and expensive, and when the components are past their useful life they have had to be thrown away.
Some of those benefits of strength and low mass can, however, be achieved by using chopped-up fibres, as BMW and Lamborghini have discovered. Those shorter lengths can be residue from a manufacturing process or even recovered from scrapped carbon-fibre components.
As an extra benefit, using chopped fibres can allow greater automation in manufacturing, which means the components are less expensive to produce.
Another area showing progress for car markers is the use of recycled plastic, which has the added environmental benefit of helping to decrease the use of oil – a factor in plastic production. Volvo says that about 5 per cent of the plastics it uses are recycled and it is aiming to raise that to 25 per cent by 2025, using old bottles, fishing nets and even car seats to make plastic parts and sound-deadening material. “We strive to manage resource scarcity by finding better ways to utilise transport and to recycle, remanufacture and refurbish products and components,” says the company.
BMW says a quarter of the interior of its i3 is made from recycled plastics along with renewable raw materials such as sustainably cultivated eucalyptus.
Resourceful thinking
In other equally imaginative examples, Cadillac makes air and water baffles for its engine compartments from used tyres, Mercedes uses recycled plastics for bumpers and baffles, plus waste paper in luggage-compartment covers. Audi also uses recycled paper and scrap cotton to make floor insulation.
And an ingenious piece of circular thinking comes from General Motors in the US. It requires suppliers to use a particular type of cardboard for packaging components, which once the parts are delivered to its factories it then recycles into sound-deadening material for the cars it makes.
Ford has said that it saves more than $10m a year in its North American plants alone by using recycled materials.
This reinforces the message that a big reason for vehicle makers to use recycled materials is cost. Another is to help them meet environmental targets for their manufacturing processes. But as companies increasingly discover that materials created through upgraded recycling processes can be lighter than the alternatives, and see those benefits multiply the efficiency, effectiveness and desirability of their products, it's likely that recycled materials will become even more common in our cars.
