Power cuts: Woods demands answers, Collins demands her sacking

Energy Minister Megan Woods has demanded answers from generators about intentional power cuts overnight, but the opposition says she knew about the problems in the system and should step down.

Transpower this morning apologised after it cut power in some areas last night to handle all-time high demand for electricity on one of the coldest nights of the year.

Woods said it was unacceptable thousands of people in the central North Island went without power for parts of the evening, and met with Transpower and the Electricity Authority to ask questions.

"New Zealand last night experienced its highest-ever peak in terms of demand for electricity in terms of 7100 megawatts. Normal winter peak we'd expect on a very cold winter's night to be about 6500 to 7000 megawatts.

"We do at the moment ... rely on gas and coal to fill these gaps in our system and if they failed us I need to know why."

She also sent a letter to generators Genesis, Contact, Meridian, Mercury and Trustpower demanding answers.

"I would like to understand all actions your company took in response to the request for more generation yesterday and that you will participate fully with any requests for information from Transpower and the Electricity Authority," she wrote.

She also demanded they immediately inform Transpower and the Authority about any problems impacting on generation at peak times, and maintaining security of power supply.

"The system has let New Zealanders down in this instance. I am seeking to ensure this does not happen again," she wrote.

She told reporters questions were also being asked of officials - including:

• Why the link between the North and South Islands was operating at just 50 percent capacity
• Why one of the generators at Huntly was not brought online
• How shortages like this could be communicated to consumers
• How much competition is in the energy market and whether it is fit for purpose

"New Zealanders have a right to expect that on a cold night that the power will stay on and they'll be able to keep the lights on and heat themselves," she said.

"I've asked a series of questions for people to go away and find some information on and I'll be able to provide updates as we get some of that information ... I want to know if these were engineering constraints or market constraints."

Transpower yesterday morning sent a notice to generators about the need for extra generation, but that was in some cases not communicated to residents until cuts to preserve the system had already begun.

Woods said that kind of notice was put out three or four times every winter, but she wanted to know more about why people were not warned with adequate time to prepare.

She said it was not a failure of renewable energy, it was a failure of a system which still relied on a large amount of fossil fuels.

Collins criticises oil and gas exploration ban

National Party leader Judith Collins said it was outrageous the government was not able to keep the lights on, and Woods would have known about the pressure points in the system and should be sacked.

"I would sack Megan Woods. She's hopeless. She knows the issue, she was their energy and resources spokesperson in 2017, she fully understands the issue and she has stood by while this very important area of natural gas has been allowed to basically be destroyed as an industry."

"Our emissions are going up, our electricity prices are going up and people lost their power last night through no fault of their own, fault of the government."

She said it was not just about the power cut itself but the fact the government was not prepared for it.

"These are Third World conditions that we don't expect in New Zealand. We had a situation where the minister and PM are yet to answer why it is that just because it was cold in Winter they couldn't keep the lights on.

"You can't operate like this. The energy system is a very complex one, and that complexity means you need to get all the pieces working together.

"We shouldn't have to use coal very much, when I was [energy] minister we had about 5 percent of energy production was coming out of coal, now it must be about 15 [percent].

The government's decision to ban oil and gas exploration in 2018 was also a huge part of it, she said.

"The exploration companies have basically shut up shop and they're not coming back until they see a decent government in place," she said.

"Actually they are incompetent, and having stopped the exploration for natural gas - instead bringing in 2,000,000 tonnes of Indonesian coal when they've got perfectly good coal right next to the power station ... it is a ridiculous situation."

"All renewable energy relies on the weather, and when that fails such as in winter it does tend to get cold ... they put in place a ban when they hadn't actually worked out how they were going to transition through, so they've now asked for a plan from their officials as to how they cope without natural gas. Well, too late now."

However, Woods said any natural gas finds since 2018 would not yet be at the point of production.

"We have not had an offshore gas find in New Zealand since 2000 so let's put this in perspective, let's take this seriously, let's look at the facts and see what actually went wrong last night, rather than making false assumptions.

"I think we need to approach what happened last night and look at the facts ... the decision that we made in 2018 about ending new exploration permits for oil and gas would not have resulted in any additional gas in the system, they would still be in the exploration, not the production phase.

Prime Minister Jacinda Ardern said the government needed more information about what had gone wrong, saying there was still a question over whether the systems already in place could have prevented the need for rolling blackouts.

"We cannot hand on heart say right now that all of the generators that could have come online did come online, and that is a critical question ... there may still be a case that this could have been prevented.

"What happened was not good enough, even if it really was a peak on an extremely cold night it's still not good enough that we were not able to warm our homes."