The Tiwai Point aluminium smelter is reducing production as a result of Covid-19.
New Zealand's largest user of electricity said it planned to shut down line four of the smelter and was talking to Meridian about reducing the electricity load which supported it.
"The work to deliver this will take place this week where we will release the Line four team of 35 people to support production on the other three full lines," NZAS chief executive Stew Hamilton said in a statement.
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Hamilton said NZAS was making the move "to support the health and safety of our employees at NZAS and in accordance with government directives in relation to containing the spread of Covid-19".
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He added: "Given the worldwide outbreak of COVID-19 and the four-week lockdown in New Zealand, our focus is on supporting our employees in a time of uncertainty and running a safe and efficient operation to meet our obligations with customers and suppliers who are also challenged at this time."
In late 2019 NZAS warned the Government that the smelter could close if it did not get relief from both high electricity and transmission prices.
It announced a strategic review which was meant to update the market about its progress by the end of March.
A spokeswoman said Tuesday's announcement was unrelated to the strategic review and declined to comment beyond a short statement.
"No decision's been made on the strategic review and we can't comment on it at the moment."
In December the company flew its global head of aluminium, Alfredo Barrios, to Wellington to directly lobby ministers.