The country's biggest consumer of electricity says unseasonably high power prices have forced it to cut production.
New Zealand Aluminium Smelters in Bluff says it is reducing its electricity consumption by 5% and producing 1500 fewer tonnes of aluminium per month.
Commercial manager Jason Franklin says he is concerned by the speed wholesale prices have risen, which are now at levels last seen during the 2008 winter crisis.
Mr Franklin says the prices are confusing, as the hydro lakes are currently above their average height for this time of year.
The Electricity Authority says it is looking into steep increases in wholesale electricity prices since the end of November.
Lobby group calls for minister to act
An electricity lobby group is calling on the Energy and Resources Minister Gerry Brownlee to put pressure on power generators to reduce the price of electricity.
The Domestic Energy Users' Network says wholesale electricity prices have shot up in December to almost three times the benchmark price, which will soon flow on to consumers.
Spokesperson Molly Melhuish says it is not clear why the price is so high when typically it falls during the summer months.
Ms Melhuish says the rise may be due to fears of low rainfall after the National Institute of Water and Atmospheric Research predicted a sustained period of dry conditions due to the La Nina weather pattern.
If power generators do not respond to ministerial pressure, then the Government should look at regulating the electricity market, she says.
