Espoo inspectors warn of dangers in electrical substations during safety checks

A yellow sign marked “Danger to Life” hangs on the door of a gray metal cube. Mika Åhlfors, project manager for the electrical network company Caruna in Espoo, unlocks the door to reveal warning labels on crossbeams, indicating that no one should reach inside, even with a camera. Rauno Järviluoma, chief expert at Kiwa Inspecta, warns of the danger of a lethal electric arc from within.

Järviluoma has conducted spot inspections this week in Espoo, Kauniainen, and Kirkkonummi, focusing on several substations completed last year. The current inspection involves a substation in Olari, where Caruna has constructed or upgraded 74 substations in 2023, added 73 kilometers of electrical cables, and replaced one kilometer of high-voltage cables. These improvements have led to fewer outages, and repairs can be carried out more quickly, with electricity consumption expected to double in the next decade.

As a TÜKES-authorized inspector, Järviluoma checks substations for the safety of passersby, users, and electricians. Previous inspections by the contractor and Caruna have identified minor issues, though not all problems have been caught in earlier checks. The Olari substation serves 250 customers, including households and electric vehicle charging stations.

During the inspection, Åhlfors reviews the substation data while Järviluoma examines its components. An incorrectly sized fuse could present a significant risk; larger fuses might not protect downstream cables and devices adequately. Järviluoma emphasizes that the robustness of Espoo’s network minimizes risks, but poorly connected cables could lead to fires or dangerous voltage changes affecting all 250 customers.

Despite occasional small issues, Järviluoma remains confident in the overall safety of Finnish substations, noting improvements in safety standards since he began inspecting them nearly four decades ago.