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The electricity market regulator says the industry is better prepared for the threat of winter blackouts this year.
Meanwhile, Transpower is promising to work with the sector to minimise risk.
About 34,000 households lost power on a cold night in August 2021, as insufficient supply was arranged for a surge in demand.
In a statement Electricity Authority chairperson Nicki Crauford said it had responded "quickly" to warnings that tight supply situations could be prevalent this winter.
With support of the system operator and industry, it had put four initiatives in place to manage these possible situations.
"It is heartening to see those in the industry - the system operator, retailers, generators and lines companies - pull together in a collaborative way to respond to the evolving nature of the electricity system," Crauford said.
Speaking to RNZ, Crauford said steps like greater information sharing will reduce the risk of blackouts, but they could not be completely ruled out.
"We can never guarantee that a blackout won't occur, we can never guarantee there won't be equipment failure or a sudden storm and things like that which will put the system under pressure.
"What we can do is we can make sure that market participants work very closely together and we can minimise that risk."
Crauford said the country was becoming more reliant on intermittent renewable sources of energy, while demand grew.
In a statement, Transpower said it was committed to working with the electricity sector to manage situations where power supply may become tight during cold snaps.
Its chief executive Alison Andrew said higher volumes of renewable but "intermittent generation" left the electricity system susceptible to faults.
"The transition to higher levels of renewables is critical but we also need other flexible generation capacity or demand response that can react quickly to support it during times of high usage," she said.
"Transpower is committed to doing what it can to ensure that consumers are not disconnected due to an electricity supply shortfall at these times, and we are working with the sector and government to put in place solutions."
If a fault did occur, Transpower general manager Dr Stephen Jay said it would work with lines companies and large industrial users to switch off "discretionary demand" to help.
"Hot water systems are regularly switched on and off by lines companies to manage peak demand, and people will not notice this," Jay said.
"We may also ask New Zealanders to help by switching off power in rooms they are not using and doing washing and charging devices and electric vehicles outside of peak times."
A "last resort" would be working with lines companies to switch off power to some consumers until peak demand passed or any fault was restored.
"[This would] prevent the risk of grid collapse, which would result in widespread uncontrolled outages that would last significantly longer."
Transpower was recently fined $150,000 for its role in the 2021 mid-winter blackouts.
An industry panel ruled Transpower breached an industry code in the management of power supplies, and communications with power companies.
