Severe storm causes rare high-voltage tower collapse in Eurajoki, Finland

A severe storm that hit Finland on Friday caused an extremely rare failure in the country’s high-voltage electricity grid. Power lines fell to the ground in Eurajoki, Satakunta, as the storm toppled two 400-kilovolt transmission towers. Prior to this, Finland had not experienced the collapse of such high-voltage towers.

Arto Pahkin, the control room manager at the national grid operator Fingrid, noted, “There have been no reports of complete tower collapses.” The incident involved guyed towers, which are supported by cables, and Pahkin estimates repairs will take about a week. Fingrid has spare towers stored for emergency situations, and additional spare parts can be sourced from ongoing construction projects for new lines.

There have been several smaller storm-related damages, including broken supports for 400-kilovolt conductors. Other causes, like foundation failures, have also resulted in a few complete tower collapses. The falling of a high-voltage line poses a serious hazard, as a live wire creates an electric field extending several dozen meters, making it dangerous even to walk nearby.

It is crucial to treat any fallen line as live. Typically, in high and medium voltage networks, automation automatically attempts to restore the voltage twice during a fault situation, essentially checking if the cause of the disturbance has been cleared.