Large transformer fire, maintenance, cause power outages across Auckland and Northland

Multiple power outages have struck across Auckland and lower Northland, leaving thousands without electricity.

One of these outages was caused by a transformer in Greenlane, central Auckland, that caught fire on Wednesday morning.

"At approximately 1:30am, Fire and Emergency New Zealand received multiple calls of a transformer on fire," station officer Steven Bolton told Newshub.

"Upon arrival, we were confronted by a large transformer fire that was impinging on a house and also the trees beside."

Bolton said three fire appliances were called to the blaze, which was threatening power lines and property.

A spokesperson for Vector told Newshub that while the transformer fire was dramatic, the impact on customers was relatively small.

"Quite a small outage really in Greenlane - it was all wrapped up by 7am," they said.

Although uncommon, transformer fires are not unheard of.

"These things do happen from time to time," said the spokesperson.

Another outage across lower Northland struck later on Wednesday morning, causing outages for thousands of people.

Transpower, Vector and Northpower customers who receive power from either the Wellsford Station or the Maungaturoto sub-station were left without power, after a wire needing replacement failed.

Puhoi, Warkworth, Wellsford, Maungaturoto, Kaiwaka, Mangawhai and Ruawai were among the affected areas.

The Vector spokesperson said maintenance by Transpower had caused outages, causing subsequent issues for Vector and Northpower.

"If something happens up the chain, it affects everyone down the chain," they told Newshub.

A Transpower spokesperson said about 22,000 customers were affected by the outage.

"In preparation for planned maintenance work due to start tomorrow, a wire we were intending on replacing failed," they said.

"Our crews were quick to find the fault and worked as quickly as they could to restore supply to Wellsford and Maungaturoto substations."

Technicians were on scene by 11am, and power was restored by 1pm.