Articles | Volume 44, issue 1
https://doi.org/10.5194/angeo-44-245-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-44-245-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
08 Apr 2026
Regular paper |
| 08 Apr 2026
| 08 Apr 2026
Benchmarking the Swedish Power Grid Against a 1-in-100-Year Geoelectric Field Scenario
Vanina Lanabere
CORRESPONDING AUTHOR
Swedish Institute of Space Physics, Uppsala, Sweden
Andrew P. Dimmock
Swedish Institute of Space Physics, Uppsala, Sweden
Sven Molenkamp Venholen
Swedish Defence Research Agency, Stockholm, Sweden
Alice V. L. Wallner
Swedish Institute of Space Physics, Uppsala, Sweden
Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
Andreas Johlander
Swedish Defence Research Agency, Stockholm, Sweden
Lisa Rosenqvist
Swedish Defence Research Agency, Stockholm, Sweden
Johan Setréus
Swedish National Grid-Svenska Kraftnät, Sundbyberg, Sweden
Related authors
Liisa Juusola, Ari Viljanen, Ilja Honkonen, Magnar Gullikstad Johnsen, Andrew Dimmock, Vanina Lanabere, and Alice Wallner
EGUsphere, https://doi.org/10.5194/egusphere-2026-1110, https://doi.org/10.5194/egusphere-2026-1110, 2026
This preprint is open for discussion and under review for Annales Geophysicae (ANGEO).
Short summary
Short summary
During severe space storms, the induced geoelectric field has the potential to cause substantial problems in power grids. We examine the geomagnetically induced currents (GIC) the geoelectric field would have driven in a simple model power grid located in Northern Europe during the May 2024 superstorm. Our results help us understand how the complicated interaction between the driving from space and the response of the conducting ground produces the most intense GIC peaks.
Liisa Juusola, Ari Viljanen, Ilja Honkonen, Magnar Gullikstad Johnsen, Andrew Dimmock, Vanina Lanabere, and Alice Wallner
EGUsphere, https://doi.org/10.5194/egusphere-2026-1110, https://doi.org/10.5194/egusphere-2026-1110, 2026
This preprint is open for discussion and under review for Annales Geophysicae (ANGEO).
Short summary
Short summary
During severe space storms, the induced geoelectric field has the potential to cause substantial problems in power grids. We examine the geomagnetically induced currents (GIC) the geoelectric field would have driven in a simple model power grid located in Northern Europe during the May 2024 superstorm. Our results help us understand how the complicated interaction between the driving from space and the response of the conducting ground produces the most intense GIC peaks.
Liisa Juusola, Ari Viljanen, Andrew P. Dimmock, Mirjam Kellinsalmi, Audrey Schillings, and James M. Weygand
Ann. Geophys., 41, 13–37, https://doi.org/10.5194/angeo-41-13-2023, https://doi.org/10.5194/angeo-41-13-2023, 2023
Short summary
Short summary
We have examined events during which the measured magnetic field on the ground changes very rapidly, causing a risk to technological conductor networks. According to our results, such events occur when strong electric currents in the ionosphere at 100 km altitude are abruptly modified by sudden compression or expansion of the magnetospheric magnetic field farther in space.
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Short summary
The goal of this study was to explore how a once-in-a-century geoelectric field event could affect the Swedish power grid by combining past storm data with a simplified model of the power grid. We identified regions that may be at higher risk and estimated how many power lines could be exposed to large voltages. These insights reveal vulnerable areas and provide a foundation for strengthening preparedness against rare, high-impact events.
The goal of this study was to explore how a once-in-a-century geoelectric field event could...
