My first thought was when and is this something that is actually happening or just a poc and it appears to be far enough along to make rapid progress. Its a good read but here are the paragraphs that I think give some sense of timeline.
Earlier this month, the Canadian firm Elysis said it hit a major milestone when it deployed an industrial-size, carbon-free anode inside an existing smelter in Alma, Quebec. Elysis is a joint venture of the U.S. aluminum giant Alcoa and global mining company Rio Tinto, both of which produce aluminum in the Canadian province.
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Rio Tinto, meanwhile, has already licensed the inert-anode technology from Elysis. The manufacturer plans to build a demonstration plant with 10 of the 100 kA cells at its existing Arvida smelter in Quebec, possibly by 2027, through a joint venture with the provincial government.