New satellite imagery and Greenpeace Ukraine analysis published on electricity grid and cooling water demonstrates important developments on the ZNPP

27 September 2025, Kyiv…The Russian government has escalated the latest crisis at the Zaporizhzhia nuclear plant to a new level of risk with the possibility that Rosatom, the Russian State Nuclear Corporation, is close to realizing its plans to restart a reactor at the Zaporizhzhia nuclear plant. As a result of Russian military action, for more than 72 hours Europe’s largest nuclear power plant has been cut off from the Ukraine grid and is dependent on emergency diesel generators to provide essential electricity supply to the safety systems of the six-reactor nuclear site. At the same time, satellite intelligence reviewed by Greenpeace experts shows the construction of electricity lines by Russian engineers is 201km between the substations in Melitopol and Mariupol in the Ukraine regions of Zaporizhzhia and Donetsk respectively. The construction had started in December 2024. 

A series of parallel and significant developments have coalesced in recent days to the point where Greenpeace Ukraine today concludes that Russia and Rosatom could use the current crisis it deliberately created of loss of external grid connection, to try and reconnect to the temporary Russian occupied grid of Ukraine to the south and east of the ZNPP. The next step could be attempts to restart one nuclear reactor. 

“Emergency diesel generators are considered a last line of defense to be used only in extreme circumstances and yet it is the deliberate actions of Russia that have caused this in cutting connection to the Ukraine external grid to the ZNPP. This has moved Rosatom closer to its long held ambition to both permanently connect to the electricity grid under its illegal occupation in Zaporzhzhia and Donetsk regions and also to restart a nuclear reactor. These are by far the most serious and consequential developments since the original Russian attack and occupation in March 2022 and have brought the nuclear plant closer to the cliff edge of disaster. It is not too late to stop Russia and it must be done,” said Jan Vande Putte, radiation and nuclear specialist at Greenpeace Ukraine.

The key developments assessed in the new Greenpeace briefing are:

  • Russian construction of a new 201km  electricity power line between the substations of Melitopol and Mariupol;
  • Deliberate Russian damage to the 750kV power line near the ZNPP within the Russian illegally occupied area, a complete disconnection from the Ukrainian controlled grid and the loss of all electricity supply to the ZNPP;
  • Completion of a new water management supply system at ZNPP cooling pond;
  • Reactor restart plans entering “final stage” according to Russian state nuclear corporation, Rostom;
  • The conflicted role of IAEA Director General in supporting Rosatom nuclear business.

Greenpeace Ukraine analysis of new additional satellite imagery from June through to 27 July 2025 showed construction had continued with the installation of 1.2km in the area close to the substation of Melitopol in temporary Russian occupied Zaporizhzhia Oblast, Ukraine, with a total of 201km installed grid lines since December 2024. The 0.5 meter resolution imagery indicates a high level of Russian activity close to the east and south of the Melitopol substation over a period of weeks from early June until late July – see below. The possibility is that while new construction was small scale compared to the period from December 2024 when many tens of kilometers were installed, the last months have been focused on the technical issues of preparing for connection to the substations of Melitopol and Mariupol.

Substation 5.5km southwest of center of Melitopol, Zaporizhzhia Oblast, UkraineImages: ©  

The nuclear crisis at Zaporizhzhia is entirely due to the illegal Russian armed occupation and it has now entered a new critical phase. The loss of electrical power is due to deliberate Russian action and Greenpeace analysis is that it is part of their plan to restart the shutdown reactors at the site. 

Cooling water crisis – sufficient water to restart a ZNPP reactor ?

Satellite image of the Zaporizhzhia nuclear plant showing the six reactor units and cooling pond and water inlet 

and outlet channels, and electrical  switchyard (right side of image) 12 August 2025. Source: © Airbus DS 2025

Satellite image of the Zaporizhzhia nuclear plant showing the six reactor units and cooling water inlet 

channel, 12 August 2025. Source: © Airbus DS 2025

Satellite image of the Zaporizhzhia nuclear plant showing section of cooling water inlet with new 

sand bar/dam built by Rosatom in June / July 2025 on left end and cooling water spray  systems. 12 

August 2025. Source: © Airbus DS 2025

IAEA Director General Grossi in Moscow 

Since 2022, the member states of the IAEA have played an important role in challenging the Russian threat to Ukraine’s nuclear plants, including at ZNPP. However, the IAEA Secretary General Rafael Mariano Grossi has sent dangerous and mixed signals about the IAEA and its policy in relation to the Russian state and nuclear industry. One day after Russian actions at the ZNPP led to the tenth loss of all external electrical power, the IAEA Director General in Moscow was a guest of honor at Rosatom’s nuclear industry conference, ATOMIC WEEK. He only had warm words for the Russian nuclear industry and his good friend Alexei Likhachev, Director of Rosatom. 

“It’s a great pleasure, a great honor to be with you at this important event, the World Atomic Week which comes as it has been so rightly been said by Mr Kiriyenko just now that comes at a very special moment for nuclear energy world-wide. To do it here in Moscow, makes a lot of sense, this country has historically been at the forefront to nuclear energy development.” IAEA Director General Rafael Mariano Grossi, ROSATOM ATOMIC WEEK, opening of the forum, 25 September 2025.

IAEA Director General Rafael Mariano Grossi and Russian President Putin, meeting in the Kremlin, Moscow, 25 September 2025. Photo TASS.

“The IAEA Director General Grossi needs to act in the interests of nuclear safety and security and not actively promote the business and strategic objectives of Russia. The Russian strategy in using the enormous threat from the Zaporizhzhia nuclear plant to gain political and military leverage must be ended. What we need to hear from DG Grossi are not warm words to his “friend” the Director of Rosatom but very clear message that the Russian government must abandon its plans for reactor restart, immediately repair the Ukraine external power line and to make clear that there is no future for their occupation of the nuclear plant,” said Shaun Burnie, senior nuclear specialist at Greenpeace Ukraine.