Rio Tinto and Contact said the restart would require about 50 megawatts (MW) of additional electricity and would deliver increased production and export earnings for New Zealand.
The Southland Wind Farm – recently approved as part of the Government’s fast-track process – is expected to generate more than 325MW of renewable electricity – enough to power 150,000 households.
The combination of new generation and industrial demand is expected to deliver strong economic benefits for the region, the parties said.
“If restarted, Line four could add around $100 million in annual export revenue, and produce about 30,000 tonnes more aluminium per year, when the line is fully operational,” Rio Tinto said.
Armando Torres, managing director Rio Tinto Aluminium Pacific Operations, said the agreement reflected a shared commitment to low-carbon growth.
“This Letter of Intent represents a practical step toward restarting Line 4 at Tiwai, strengthening New Zealand’s position as a producer of low-carbon aluminium, supporting jobs, increasing exports, and contributing to a more resilient electricity system,” Torres said.
“The aluminium produced by Tiwai is in high demand and is an essential part of the energy transition globally.”
Michelle Henderson, NZAS general manager, said the restart of line four was a welcome further development, following the securing of long-term energy contracts for the smelter in 2024.
“Building on our existing electricity arrangements with Contact, we are pleased to have them partner on the potential restart of Line 4.
“If approved, this increased production – targeted for 2030 with potential to be brought sooner – would bring more economic activity to Southland, further strengthening the local economy, and reinforcing Rio Tinto’s commitment to Southland into the future,” Henderson said.
Contact chief executive Mike Fuge said the partnership with Rio demonstrated how renewable energy investment could be accelerated by committed customers.
“Having a credible baseload partner such as Rio Tinto is critical for bringing new renewable generation online.
“This letter of intent helps underpin our Southland Wind Farm and shows how industry and renewable energy can work together to deliver long-term benefits for both Southland, and New Zealand,” Fuge said.
Ngāi Tahu representative Terry Nicholas said the deal strengthened the tribe’s partnership with Rio and Contact.
“This agreement strengthens our growing partnership with both Rio Tinto and Contact, ensuring that future industrial growth reinforces our commitment to environmental taurikura (prosperity) and community resilience,” Nicholas said.
Jamie Gray is an Auckland-based journalist, covering the financial markets, the primary sector and energy. He joined the Herald in 2011.
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