The Ronal Group is supplying aluminum wheels for Audi’s new e-tron GT electric sport sedan that are made using Alcoa Corp.’s Elysis low-carbon smelting process to reduce carbon dioxide emissions from their manufacture by 75 percent. The result is 40 kg (88 lbs.) of CO2 released per wheel, in comparison to the average of 163 kg per wheel, which is the average for European production, according to Ronal.
The company buys carbon offsets for the remaining 25 percent, leading them to claim carbon neutrality for the wheels. Whether or not purchased offsets should count, the 75 percent reduction is still an impressive accomplishment.
Ronal makes the wheels in Landau, Germany using 100 green electricity, though it doesn’t specify the source or type of energy production. The wheels are made of aluminum that includes some which is recovered from pre-consumer and post-consumer sources
“Aluminum is the focus of our CO2 program because producing this material requires a high energy input,” explained Marco Philippi, Audi AG’s Head of Procurement Strategy. “We are therefore actively searching for innovative processes that help reduce CO2 emissions as early as possible in the creation process. These kinds of innovations allow us to increase our sustainability performance in the supply chain and ensure that our models arrive at the customers with a smaller carbon footprint.”
The Elysis smelting technology causes no direct CO2 emissions when compared to the traditional process used to make aluminum, Alcoa reports. The process uses a so-called inert anode that replaces the carbon anodes that are traditionally used during the electrolysis makes primary (non-recovered or recycled) aluminum. An inert anode is insoluble in the electrolyte under the conditions during electrolysis.
Further, the e-tron GT’s wheels are made using Alcoa’s low-carbon EcoLum metal, which is produced with less than 4.0 metric tons of CO2e for every ton of metal produced, according to Audi. That includes both direct and indirect emissions across the entire production chain, even including bauxite mining and alumina refining.
“One focus of our sustainability strategy is reducing our CO2 emissions, which we plan to halve by 2030," said Patrick Lämmli, Ronal Executive Vice President Group Sales. “In recent business years, we have already reduced the ecological footprint per wheel, mainly by purchasing aluminum produced with renewable energy.
The 20-inch e-tron GT wheels include other special features too. They are manufactured using flow-forming technology for weight optimization. And a special propeller-shaped rim design contributes to the GT’s 0.24 coefficient of drag. The wheels’ mounted “propeller” blades are just 2-3mm thick and largely cover the wheels to aid aerodynamic efficiency. Even the e-tron GT itself benefits from green manufacturing, as its Böllinger Höfe assembly plant relies on renewable energy from a biogas-operated combined heat and power plant.
“We’re proud to help the industry take another step forward to lower the carbon footprint of global supply chains,” said Tim Reyes, Alcoa’s Chief Commercial Officer and Executive Vice President. “Our partnership with the Ronal Group in supplying Audi with sustainable solutions helps make an innovative vehicle even more exciting for consumers.”