Transpower thanks everyone for their patience in dealing with power outages that affected some consumers across the North Island yesterday evening.
The outages occurred as record demand coincided with insufficient generation which resulted in the need to reduce demand to maintain system security.
General Manager Operations Dr Stephen Jay said: “We apologise to everyone who was affected last night. It is fair to expect electricity to be there for people when they need it most, especially on one of the coldest nights of the winter.
“Last night, demand over the evening period reached record levels of around 7,100 MW between 6 pm and 6:30 pm.
“Unfortunately, there was not enough generation to meet demand. As a result, Transpower had to ask all the local lines companies and large industrial users to reduce demand to help keep the system in balance. Beyond temporarily cutting power to hot water cylinders, some customers were disconnected.
Together with the sector, we will work to understand why there was not enough last night, to avoid a repeat.”
Under normal circumstances there is typically more generation available in the system so that it can cope with high demand as well as the potential for other faults.
“With the widespread cold weather, we had been looking ahead to the evening peak throughout the day;” explained Dr Jay. “We expected things to be tight due to some major generating units being unavailable and signalled to the market that other generation was required, and that demand should be voluntarily reduced where possible.
“Unfortunately, this is what came to pass. The prompt action of local lines companies and others in reducing demand helped keep the system in balance and prevented even wider problems.
“Problems such as last nights are very rare indeed and we will now be working with the sector to do all we can to avoid a repeat.”