Ferosplavna-1

Ferosplavna-1 is the 330 kV backup feeder line that provides an alternative external power supply to Zaporizhzhia Nuclear Power Plant (ZNPP) when the primary 750 kV Dniprovska line fails. In April 2026, when the Dniprovska was repaired via an IAEA Ceasefire and then lost again, repair crews reached the Dniprovska switchyard and simultaneously discovered additional damage on the Ferosplavna-1 line approximately 1.8 km from the switchyard. At that point, one external line was running, the only thread of grid connectivity keeping the plant off diesel generators.

The Ferosplavna-1 line operates at a lower voltage than the primary Dniprovska feeder, making it less capable of sustaining full plant loads. It has been the subject of IAEA-brokered Ceasefire repairs, an April 2026 Ceasefire was specifically negotiated to restore it. The pattern across both power lines shows a structural vulnerability: Ceasefire repairs restore a line, then fighting resumes and damages it again, cycling the plant through repeated blackouts. ZNPP has lost all external power sixteen times since the full-scale invasion began.

The IAEA treats Ferosplavna-1 as the last-resort grid connection before ZNPP falls onto diesel-only operation. The combination of a disconnected primary line (Dniprovska, out 50 days as of 13 May) and a damaged backup places the plant in what nuclear safety protocols classify as a degraded external power state, one category below full loss of coolant, but with the same directional trajectory.

The pattern held through mid-2026: when the Dniprovska Ceasefire collapsed on 11 June, ZNPP's 19th total blackout again Left Ferosplavna-1 as the plant's sole functioning external line before diesel generators would have been the only remaining fallback. By mid-July the IAEA reported the plant had lost off-site power for the 22nd time since 2022, with ten of those twenty-two losses in the preceding three months, an accelerating rate that has made Ferosplavna-1's reliability the decisive factor in how long each blackout lasts.