Combustion engines aren’t environmentally friendly to manufacture, but then neither are EVs.
The entire chain between raw materials and the final vehicles rolling off the production line needs to be visited to help make the automotive industry more sustainable. And it hasn’t escaped the notice of OEMs.
More manufacturers are now looking at their entire operations to see where they can clean up their act even further. And perhaps surprisingly many of the luxury brands – which you’d think would have to worry less about their footprints owing to smaller production scales – are making some of the biggest changes.
Bentley, well known for the uber-luxury limousines and SUVs it produces, is heading towards end-to-end carbon neutrality by 2030.
It’s an enormous shift, from the world’s largest producer of 12-cylinder petrol engines to having no internal combustion engines within a decade. But it’s only part of the jigsaw and is something the firm has been working on for a number of years.
Bentley’s facility in Crewe became the first luxury automotive factory in the UK to be certified carbon neutral by the Carbon Trust. It was a 20-year journey of implementing new solutions including: a water recycling system in the paint shop, tree planting, installation of a 10,000-solar panel carport, taking the total number of on-site solar panels to 30,000, and a switch to renewable-only electricity.
And the work continues; by the end of 2025, the company intends to reduce its factory environmental impact by focusing on energy consumption, CO2 emissions, waste water, use of solvents in the paint process and becoming plastic neutral.
Arguably for Bentley, which makes 11,000 vehicles a year, the challenge isn’t that great. But what about an OEM that delivers over 1.5 million vehicles a year?
It’s an enormous job, but the wheels are in motion. From 2026 onwards Audi will only design new models powered purely by electricity (although it will continue to build and sell ICE models until 2032). As part of that shift the marque is working to optimise every link in its value chain and expanding its use of renewable energy.
Everything’s up for review: sourcing of raw materials, production, utilisation and recycling or reuse at the end of a car’s life.
The transition to electric mobility means some carbon emissions are transferred to the supply chain – lithium-ion batteries require energy-intensive production, for example. And it’s worth noting that almost a quarter of all carbon emissions per car at Audi will be produced because of the battery. It’s why Audi is looking at second-life uses for the technology once it can no longer power a car and ultimately recycling the packs.
Second-life applications could include electricity storage to cover peak demand on national networks.
Closed material loop
Recycling comes in when batteries can no longer fulfil their second-use applications and are dismantled into raw materials to be used again in new batteries.
Audi’s parent company, Volkswagen, has a pilot recycling facility for lithium-ion batteries in Salzgitter, Germany that serves this purpose. Analysis software tests the health of the battery and checks whether it still has enough power for reprocessing – for instance into mobile energy-storage units such as flexible fast-charging stations or charging robots. The aim is to establish a closed material loop for batteries.
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