BMW announced today that it and the Mini brand will transition to aluminum wheels made using only renewable energy starting in 2024.

In particular, green power will help shrink the carbon footprint of the electrolysis process used in the making of aluminum and in the wheel-casting stage of construction. Together, these measures will help cut 500,000 tonnes of CO2 emissions per year, BMW predicts.

“Green power is one of the biggest levers for reducing CO2 emissions in our supply chain,” said Joachim Post, head of purchasing and supplier networks for BMW. “We have already signed more than 400 contracts with our suppliers, including suppliers of wheels and aluminum, requiring them to use green power.”

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Further helping BMW in its mission is the ease with which aluminum is recycled. The automaker plans to take advantage of this property to melt down old wheels and use the material to make new ones.

Mini will be a pioneer in this regard and will start using light-allow cast wheels made of 70 percent recycled aluminum in the Mini Countryman starting in 2023. These wheels, when made with 100 percent renewable energy, help cut down CO2 emissions in the manufacturing process by as much as 80 percent.

Those will be important savings because the BMW Group buys about 10 million light-alloy wheels per year, 95 percent of which of made from cast aluminum. As such, ensuring that they’re made using green power is a complicated process, but one that will help BMW in its mission to become a green automaker.