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Russia-Ukraine War 2026
13MAY

ZNPP on sole backup line for 18 days

2 min read
20:00UTC

IAEA Update 346 disclosed that Europe's largest nuclear plant has been running on a single backup power line since 24 March, with no sixth repair ceasefire brokered.

ConflictDeveloping
Key takeaway

Europe's largest nuclear plant is one cable away from diesel-only cooling.

IAEA Update 346, published on 10 April, disclosed that the main 750 kV Dniprovska power line feeding the Zaporizhzhia Nuclear Power Plant (ZNPP) has been disconnected for eighteen days, with no sixth repair ceasefire brokered 1. The plant is running on its sole remaining backup, the 330 kV Ferosplavna-1 line, which was reconnected on 5 March under the fifth IAEA-brokered local ceasefire . Director General Rafael Grossi stated the damage to the Dniprovska line is "located over the Dnipro River, which is the frontline in this area."

A further hit to the Ferosplavna-1 line, from artillery, a drone, or incidental damage along the Dnipro River frontline, would push all six reactor units onto emergency diesel generators with finite fuel. Rosatom has separately confirmed none of the units can be restarted while fighting continues. The redundancy posture echoes the pre-accident configuration at Fukushima Daiichi in March 2011, though ZNPP's shut-down condition and cooler fuel materially reduce the comparable risk.

Russia's Rostekhnadzor issued ten-year operating licences for units 1 and 2 on 2 April , a bureaucratic signal that Moscow intends to keep the plant under Russian administration for a decade regardless of any negotiated outcome. Wire services have not carried this. The quiet three-week disconnection is the kind of fact that does not move until it fails.

Deep Analysis

In plain English

The Zaporizhzhia Nuclear Power Plant, Europe's largest, has been occupied by Russia since 2022 and is located on the front line. It has six reactors, all shut down, but they still need continuous electrical power to keep the cooling systems running. For 18 days, the plant's main power line has been broken, leaving it dependent on a single backup line. If that backup line is also cut, the plant would rely on emergency diesel generators. The concern is that a failure of both the backup line and the generators could lead to the cooling systems failing, potentially causing a nuclear accident.

What could happen next?
  • Risk

    Any strike on the Ferosplavna-1 330 kV backup line pushes all six reactor units to diesel generator cooling, which IAEA has previously flagged as the final safety boundary before cooling failure risk.

  • Meaning

    Rostekhnadzor's issuance of 10-year operating licences for ZNPP units 1 and 2 on 2 April signals Russia's intent to restart the plant under occupation, which would sharply increase the safety stakes of the current grid vulnerability.

First Reported In

Update #12 · Three narrowings of US support for Kyiv

International Atomic Energy Agency· 11 Apr 2026
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Different Perspectives
NATO eastern flank (B9 + Nordics)
NATO eastern flank (B9 + Nordics)
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IAEA / Rafael Grossi
IAEA / Rafael Grossi
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Péter Magyar / Hungary
Péter Magyar / Hungary
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EU Council and European Commission
EU Council and European Commission
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Donald Trump / White House
Donald Trump / White House
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Vladimir Putin / Kremlin
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