Eight things to do when a power cut strikes

In 2014, a lot of east Auckland was left in darkness following a fire at an electricity substation in Penrose. Photo / Janna Dixon

This morning, and early into the winter season, the country's power supply came under threat, meaning it's probably not a bad time for Kiwis to freshen up on what to do during a power cut.

Transpower issued a nationwide warning notice shortly before 8am - revealing there was a risk of insufficient power generation and reserve to meet the country's demand - as Kiwis woke to a bitterly cold day.

Power outages can be unexpected and caused by insufficient power supply, damage to lines and during storms.

Knowing what to do during a blackout is important.

1. Unplug electrical appliances: Power spikes and surges can cause damage to your items and homes so it's best to unplug them all.

2. Use a flashlight: While you might want to reach for a candle it's better to opt for a battery-powered torch instead, these minimise the risk of fire significantly.

3. Make it last: Keep the fridge closed so food will last longer while the power is off, and pack food close to one another to retain its chill.

4. Stock up on wool blankets: Keeping warm during a power cut in winter can be tricky, pull together all blankets you have and consider buying ones made of wool. Put on extra layers of clothing and if you have it, use another heating source such as a wood burner.

5. Save your phone battery: Don't be tempted to play on your smartphone while you wait it out, save your battery to be able to use your phone for emergencies and to check for updates from local power companies. Also, dim the screen brightness to help save the battery.

6. Fill up sinks and the bathtub: When a power cut strikes, there's a chance that tap water supply will also be impacted. Fill up the bathtub and sinks to make sure you have enough water for drinking and washing.

7. Avoid travelling: There's a chance that traffic lights will not be working during a power outage so unnecessary travel should be avoided. If you do have to travel be cautious at intersections and use the give way rules.

8. Have some old-fashioned fun: Being plunged into darkness doesn't have to be scary. Take the opportunity to read stories or books to your kids, or play games with them. Dig out those old board games or see who in the family is best at charades. It can be a welcome change from Netflix, video games or social media.

Today's grid emergency was due to loss of generation from three sources including a Contact Energy power station, Genesis' power station in Huntly and a wind drop from 90 to 30 megawatts, said Transpower chief executive Alison Andrew.

It meant lines companies were asked to reduce their controllable loads which impacts things like hot water cylinders - Andrew said most New Zealanders wouldn't have known there was a disturbance.