Ukraine’s electricity system was on Saturday afternoon still stable and maintaining supplies to the war-torn country – but its largest energy company said Russian tanks were less than 50km from the nation's two largest power stations and warned damage to key infrastructure could cause major disruption at any moment.

Executives from DTEK in a special briefing to international media gave an extraordinary insight into their efforts to keep the energy system operating for their population of 44 million amid a full-scale invasion that started on Thursday, outlining measures taken and the impact so far on its assets (see panel).

Ukraine's energy system on war footing

DTEK executives gave media a snapshot of its own operations, and the wider Ukrainian energy system, on the third day after Russia invaded its territory. CEO Maxim Timchenko revealed:

  • Ukraine’s government has ordered power producers to prioritise gas-fired generation over coal to preserve strategic coal reserves that would support 15-20 days operation unless topped up.
  • Eleven of 15 nuclear reactors are operating.
  • Seven of DTEK’s eight thermal plants are operating – the other is in Russian hands.
  • Forty per cent of DTEK’s 1GW renewable capacity is offline due to damage to wind power transmission lines that cannot be repaired.
  • All but four of DTEK’s 39 gas wells are still producing.
  • Talks are underway with Poland over the potential supply of coal to power plants in the Ukrainian west.

Maxim Timchenko, CEO of DTEK – whose interests span coal and gas production through to thermal and renewable power generation, and accounts for roughly a quarter of Ukrainian electricity – said Russian troops do not currently appear to be attempting to damage critical infrastructure such as power plants.

Consumers in most regions were still served by power supplies, with drastically reduced demand from heavy industry that has ceased operating meaning the system is currently in surplus capacity. “As of today, from a technical point of view, the system is stable [but] nobody can predict tomorrow,” Timchenko said.

The energy group warned the stability of the Ukrainian power system could come under severe strain in the event of accidental or deliberate damage to key infrastructure.

Timchenko said he hoped Russian “madness” is “not at the level to start shelling nuclear power units” but warned that the unpredictable nature of war meant it couldn’t be ruled out.

On Saturday afternoon Russian tanks were within 50km of the site of the two biggest power plants in Ukraine – the 6GW Zaporizhzhia nuclear station and DTEK’s own 3.6GW thermal facility in Enerhodar in the nation’s south – said Dmytro Sakharuk, DTEK executive director and leader of the company’s crisis team.

“A critical situation may happen if some big element of the energy system is damaged or destroyed,” such as a major power plant or substation, Sakharuk warned.

In that event, the Ukrainian network operator could struggle to achieve the flexibility needed to balance the system, due to its ongoing operation in “isolation mode” from the Russian and Belarusian systems with which it has been historically entwined.

“There would be no reserve we could use,” said Sakharuk, explaining that the network operator would not have the last-resort option to call on a neighbouring supplier, raising the risk of a system-wide failure.

Timchenko called on European energy officials to speed up efforts to integrate Ukraine’s power network with the European ENTSO-E system, to allow it to replace its previous connections with Russia and Belarus.

“From a political point of view it would be a very good move… to accelerate full integration into ENTSO-E,” a move he said would give “very, very serious support to the stability of the system.

“As far as I know there is no critical technical limitations. If there is a will from European side this process can be done in months, if not weeks,” he said.