STNG: 2025 – 2030
Work Package II: This Work Package aims to expand the capabilities of NZ’s existing geomagnetic field observations to provide near real-time GMD awareness, GMD magnitudes, and NZ space weather impacts. Improvements will be made to the MANA magnetic network to produce measurements at near real-time at all sites and relocate instruments to provide better NZ coverage. The extended MANA and ESNZ magnetic network will continue to operate throughout the STNG programme.
Leaders: Johnny Malone-Leigh (Otago), Tanja Petersen (ESNZ)
Work Package V: If power grid operators are to respond and recover from an extreme space weather event the correct operation of the grid’s protection systems is crucial. During the largest space weather events there are risks that the protection systems could mis-operate or fail. We will test these systems under NZ-representative extreme space weather conditions and develop engineering solutions to the expected space weather impacts. Equipment designed to protect the power grid will be obtained from the Electricity Industry Space Weather Working Group and tested under extreme GIC scenarios to evaluate their performance and develop engineering solutions to anticipated space weather impacts.
Leader: Andrew Lapthorn (Canterbury University)
ST1: 2020 – 2025
Work Package II: Testing the electrical conductivity of the ground and subsurface around New Zealand. Which powerlines and transformers are affected by geomagnetically induced currents (GIC) is very much dependent on the electrical structure of the Earth as this dictates the orientation and size of the induced voltages which drive these currents. The electrical conductivity of the Earth at a location can be measured using a technique called magnetotelluric sounding (MT) in which variations in induced currents in the ground are measured and related to simultaneously measured variations in the earth’s magnetic field. GNS Science and VUW have made many such measurements over significant portions of New Zealand, however the Otago/Southland and Northland regions have yet to be surveyed and are the focus of this work package. In particular, given the proximity to the auroral zone, understanding the structure in Otago/Southland is critical to modelling how magnetic storms may impact the power network.
Leaders: Wiebke Heise (GNS), Malcolm Ingham (VUW)
Work Package VI: There is evidence that transformers, a critical part of the electricity grid, are deteriorated by repeated geomagnetic disturbances. Transpower is New Zealand’s state-owned enterprise responsible for power transmission. Tests will be done on Transpower’s transformers, simulating geomagnetic storms by injecting DC current into operational transformers, and undertaking dissolved gas analysis to determine the levels of deterioration and damage.
Leaders: Andrew Lapthorn (Canterbury University)
