Tens of thousands of North Island properties were left without electricity overnight because of damage caused by bird strike.
The power went off to about 46,000 customers in Coromandel, Thames Valley and Hauraki Plains just after 10pm and was out for about two hours.
National grid operator Transpower says a bird flew into a piece of major equipment at the Waihou substation.
It says the equipment operated as it should and automatically disconnected from the power network to stop any other damage.
Distributor Powerco says the incident cut electricity to 18 Powerco substations.
The company says these acts of nature happen from time to time.