13 May 2024
The G5 geomagnetic storm affecting Earth has now subsided to the extent Transpower has been able to restore all electricity transmission circuits to service.
Transpower had switched off some circuits across the country on Saturday as a precaution to prevent damage to equipment as a result of the solar storm.
There was no impact on New Zealand’s electricity supply.
Transpower thanked Professor Craig Rodger from Otago University for his expertise and advice. Transpower has been working with Professor Rodger on developing protocols for dealing with space weather for many years. His input has been invaluable in developing the procedures implemented to protect the grid during this event.
Although there was no impact on electricity supply, Transpower said the event is a good reminder to New Zealanders that they should be prepared for a natural disaster or other major event that could interrupt their power supply and damage other infrastructure.
New Zealanders should familiarise themselves with civil defence advice and have plans in place if they were to be without electricity for several days.
Geomagnetic storm explainer
Coronal mass ejections (CMEs) are explosions of plasma from the sun that are ejected out into space. The vast majority of these do not impact the Earth but in the rare chance that they do, the CME causes a geomagnetic storm on Earth.
While the impact usually goes unnoticed by most people because Earth’s magnetic field shields us from the particles, it can cause issues with electricity grids, radio signals and other infrastructure.
In a severe geomagnetic storm, the CME interacts with the Earth’s magnetic field, disrupting it and therefore inducing additional electrical currents down long electricity transmission lines. These additional currents can damage equipment essential to transmitting and generating electricity, such as power transformers.
To reduce the risk of that from happening for moderately strong CME events that could impact New Zealand’s electricity supply, Transpower removes some transmission lines from service to reduce the magnitude of these additional currents.
For more information, call Transpower’s media phone: 021 195 8613