Transpower issued a nationwide warning notice shortly before 8am yesterday – revealing there was a risk of insufficient power generation and reserve to meet the country’s demand.
Last week, many Dunedin residents went without hot water one evening.
Power outages can be unexpected and caused by insufficient power supply, damage to lines or storms.
Yesterday’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 90MW to 30MW, Transpower chief executive Alison Andrew said.
It meant lines companies were asked to reduce their controllable loads, which affects items such as hot-water cylinders.
Mr Andrew said most people would not have known there was a disturbance.
Knowing what to do during a blackout is important.
• Unplug electrical appliances: power spikes and surges can cause damage to your items and home.
• Use a torch: while you might want to reach for a candle it is better to opt for a battery-powered torch, thereby minimising the risk of fire.
• Make it last: keep the fridge closed so food will last longer while the power is off, and pack food close together to retain its chill.
• Stock up on wool blankets: keeping warm during a power cut can be tricky in winter. Check how many blankets you have and consider buying wool ones. Put on extra layers of clothing.
• Save your phone battery: don’t play on your smartphone while you wait it out. Save your battery so you can use your phone for emergencies and to check for updates from local power companies. Also, dim the screen brightness to help save the battery.
• Fill up sinks and the bathtub: when a power cut strikes, there is a chance tap water supply will also be affected. Make sure you have enough water for drinking and washing.
• Avoid travelling: there is a chance 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 adhere to give-way rules.
• Have some old-fashioned fun: being plunged into darkness does not have to be scary. Take the opportunity to read stories or books to your children, 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.