Fears grow for winter power supplies

New information has been released about the capacity of Huntly power station. File picture / Amos Chapple

The Electricity Commission has admitted its risk assessment of a power shortage this winter has been over-optimistic, National's energy spokesman Nick Smith said today.

The commission has released new data that shows it previously had over-estimated how much power was available from the Huntly power station and the Waitaki river.

The reassessment increases the threshold at which power savings will be needed and when power cuts would take place.

Actual storage is still above those levels at this point.

Dr Smith said it was "hugely significant" that the commission had lifted its levels by 15 per cent because it had over-forecast the amount of power available.

"This change raises serious questions about the confidence people can have in the Electricity Commission," Dr Smith said.

This morning Economic Development Minister Trevor Mallard was the latest minister to assure the public that the electricity system should be able to meet demands this year.

Mr Mallard said the Electricity Commission was keeping him up to date and he was "listening very carefully" regarding lake levels.

"While I'm currently advised that we can expect the electricity system to be able to meet the demands placed on it this year, I acknowledge that the margins are getting very tight and the situation could get worse."

Former energy minister David Parker had said there would be no rolling blackouts this winter.

Dr Smith said those assurances were based on incorrect advice.

"It is now highly likely that a consumer savings campaign will be required to help avoid blackouts," Dr Smith said.

- NZPA