Space weather and the power system

Transpower not only monitors weather here in Aotearoa but also weather in space that can affect our power system.

Space weather is when the Sun ejects plasma and other matter in Earth’s direction. These coronal mass ejections (CME) are extremely rare, and most people won’t notice because our planet’s magnetic field shields us from the particles.

However, these CMEs can cause geomagnetic storms on Earth, and these storms can send unwanted currents through the long electricity circuits that we manage. When the currents reach transformers in our substations or the large hydroelectric dams, they can cause extensive damage. 

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Coronal Mass Ejection picture

To minimise the risk of damage to critical equipment, Transpower may work with industry to switch off some parts of the power system for a time in a severe solar storm. These events are rare, but we are prepared for them and have a plan in place.  

We recognise the inconvenience of power cuts and will do our best to minimise any disruption. And the actions we take with wider industry will ensure that power will come back on when the storm subsides, which could take several days in an extreme event.

If we don’t do this and equipment is damaged, it could require expensive and time-consuming repairs or the total replacement of equipment before full power can be restored across the country.

What can I do to prepare?

The risk of an extreme solar event impacting the power system is small. But New Zealanders need to remember that all infrastructure can be vulnerable at any time to a natural disaster or other major event so should always be prepared.

You and your family should familiarise yourself with Civil Defence advice, and always be prepared to be without electricity for several days. Find out more at NEMA’s Get Ready site

People who need power for medical reasons are asked to ensure they have a backup plan in place.  

Want to know more about space weather?

While space weather can be nuisance for people running the power system, in most cases Kiwis don’t have to worry and can sit back and enjoy the stunning auroras or light displays they produce in the sky. 

If space weather has tickled your inner scientist and you want to know more, check out this video

You can also learn about the Solar Tsunami Endeavour Programme, an exciting international collaboration led by the University of Otago to understand how New Zealand’s energy infrastructure will be impacted by an extreme space weather event. 

For the latest space weather forecast check out the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Centre.