Alinta Energy is proposing a 1,000MW wind farm off the coast of Portland in Victoria that could help power the Portland aluminium smelter with up to 100 per cent renewables, and inject green energy into the country’s main grid.

The $4 billion Spinifex offshore wind project, first flagged by Alinta CEO Jeff Dimery in an interview on RenewEconomy’s weekly Energy Insiders podcast in October, would be sited about 10km off the coast of Portland.

Spinifex would connect to the grid via the smelter’s switchyard – which accounts for more than 10 per cent of the state’s electricity demand – and make the site among Australia’s first smelters to be powered by up to 100 per cent renewables.

Australia’s other large aluminum smelters, at Tomago in NSW and Boyne Island in Queensland, are already committed to switching to a 100 per cent renewable energy supply before the end of the decade, according to plans by owner Rio Tinto to invest in more than 7GW of wind power. and solar energy.

Alinta believes that the Spinifex project will need to be sized at around 1,000MW to make it commercially viable, and it points out that the project is still in its very early stages, with the exact location and turbine size yet to be determined.

Spinifex is one of more than a dozen proposed offshore wind projects in Australia – which can now move forward after the adoption of legislation allowing such projects – but is the first to identify a major customer that could enable it to jump from other proposals.

Portland is a joint venture between Alcoa, Citic and Marubeni, and smelter manager Ron Jorgensen said the “exciting” offshore wind proposal, adapted to the aluminum industry’s direction to decarbonize, will help improve the smelter’s long-term viability.