Tiwai Point Aluminium Smelter (1971-present)
The Tiwai Point smelter near Bluff opened in 1971, built to use power from the Manapouri hydro scheme. It consumes about 13% of New Zealand's electricity and has repeatedly threatened closure over power price negotiations, most recently in the 2020s.
In 2024, Mercury signed an agreement to support the smelter, providing near-term certainty and enabling the Kaiwera Downs stage two expansion.
The smelter's future remains uncertain. If it closes, Southland would have a large electricity surplus, potentially affecting the economics of new wind farms in the region.
The smelter's power demand is a key reason new wind generation is being built in Southland. Its potential closure is a major variable in the region's energy planning.
