The facility, which involves an investment in excess of £130 million and will sustain and create around 570 jobs, was unveiled by industrial group GFG Alliance in September.
Lying to the west of the existing aluminium smelter in Fort William, the proposals for the Liberty Aluminium Lochaber Ltd facility include redevelopment of part of a former brownfield site on which a former carbon factory stood.
Architects Keppie Design said the factory buildings have been designed to look like aluminium ingots (or slabs).
Councillors approved the significant planning proposals subject to a number of detailed conditions relating to transport and traffic management; environmental management; and historical and archaeological management among other conditions.
Chair of the council’s south planning applications committee, Councillor Jimmy Gray, welcomed the decision as a “huge turnaround for the Highlands and in particular Lochaber”.
He added: “There are very few areas in Scotland and indeed the UK where we could see such a dramatic investment in manufacturing and industry. This is the only aluminium smelter left in the UK so this is of national significance. There is a real potential for Liberty to invest in Fort William and Lochaber and we have a whole change agenda in this development that provides huge opportunities.
“I would like to commend and give thanks to our local planning team and the officers involved who processed and prepared this major planning application. This was an extensive piece of work and they have done an excellent job.”
Lochaber leader, Councillor Andrew Baxter, added: “This is a once in a generation opportunity and Liberty Group should be applauded for this contribution to the economy and community. Up to 400 direct jobs will be created at the facility which will also help secure the existing 170 jobs at the smelter.”