Auckland's coldest day in three years had locals turning on the heaters, with energy provider Vector experiencing its second highest amount of power used on record.

And with temperatures in some parts of the country's largest city dropping as low as 0.2C, it's hardly surprising.

Yesterday, Aucklanders used 32.8 gigawatts hours of power – enough to light up a full Vector Lights show on Auckland's harbour bridge and have it running every night for more than 167 years.

That was the highest demand for electricity across Vector's network this year, and 2.3 gigawatts hours more than last winter's heaviest usage day.


At roughly 6pm last night, Aucklanders used 1833 megawatts of energy instantaneously, second only to the winter of 2012 when peak usage reached approximately 1941 megawatts.

To put that in perspective, 1833 megawatts of energy would be enough to power 450 floodlight lit rugby games in stadiums the size of Eden Park at the same time.

Andre Botha, Vector's chief network's officer, said they were really pleased to see that the network responded well to the rapid surge in power.

"That's a lot of power and we're really pleased to see that despite the rapid surge in demand the network responded well," Botha said.

"The seasons play a big role in how we manage the network and every year at the start of winter we work hard to ensure we are doing everything we can to deliver a consistent experience for customers."

And with meteorologists predicting a colder than normal winter in 2018, the highest peak may still be yet to come.

"We're continually investing in making the network more resilient. We're also investing heavily in new technology to meet customer expectation and help improve the way we distribute energy across the network, which will play an increasingly important part as seasonal weather patterns become harder to predict," Botha said.