KYIV (AFP) — Ukraine was scrambling to turn lights and heating back on Sunday after Russian attacks targeting energy infrastructure, with the state’s power provider saying its generating capacity was reduced to “zero.”

Moscow, which has escalated attacks on Ukraine’s infrastructure in recent months, launched hundreds of drones at energy facilities across the country overnight into Saturday.

The attacks interrupted electricity, heat and water supplies in several cities, with state power firm Centerenergo warning its generating capacity “is down to zero.”

“An unprecedented number of missiles and countless drones —several per minute — targeted the same thermal power plants that we had restored after the devastating attack of 2024,” Centerenergo said in a statement.

Power would be cut for between eight and 16 hours a day across most regions of Ukraine on Sunday, state power transmission system operator Ukrenergo said, while repairs were carried out and energy sourcing diverted.

Ukraine’s energy minister called it “one of the most difficult nights of the entire full-scale war.”

While the situation had somewhat stabilized, regions including Kyiv, Dnipropetrovsk, Donetsk, Kharkiv, Poltava, Chernigiv and Sumy could continue to see regular power cuts, Svitlana Grynchuk said Saturday evening.

“The enemy inflicted a massive strike with ballistic missiles, which are extremely difficult to shoot down. It is hard to recall such a number of direct strikes on energy facilities since the beginning of the invasion,” she told local broadcaster United News.

Russian drones had targeted two nuclear power substations deep in western Ukraine, Kyiv’s Foreign Minister Andrii Sybiha said, calling on the United Nations’ nuclear watchdog to respond.

The substations powered the Khmelnytskyi and Rivne nuclear plants, around 120 and 95 kilometers, respectively from Lutsk, he said.

“Russia is deliberately endangering nuclear safety in Europe. We call for an urgent meeting of the IAEA Board of Governors to respond to these unacceptable risks,” he wrote on Telegram late Saturday, referring to the International Atomic Energy Agency.

Sybiha also urged China and India — traditionally large buyers of Russian oil — to pressure Moscow to cease its attacks.

Winter without heat?

Of the 458 drones and 45 missiles launched by Russia overnight into Saturday, Ukraine’s air force said it downed 406 drones and nine missiles.

Experts said the strikes on energy infrastructure put Ukraine at risk of heating outages ahead of the winter months.

Russia has targeted the power and heating grid throughout its almost four-year invasion, destroying a large part of the key civilian infrastructure.

The barrage overnight into Saturday was the ninth massive attack on gas infrastructure since early October, Ukraine’s energy company Naftogaz said.

Kyiv’s School of Economics estimated in a report that the attacks shut down half of Ukraine’s natural gas production.

Ukraine’s top energy expert, Oleksandr Kharchenko, told a media briefing Wednesday that if Kyiv’s two power and heating plants went offline for more than three days when temperatures fall below minus 10C, the capital would face a “technological disaster.”

He said Ukrainian cities, which mostly rely on central heating, should prepare contingency plans to prevent buildings from freezing in case heating supplies are destroyed.

Ukraine has in turn stepped up strikes on Russian oil depots and refineries in recent months, seeking to cut off Moscow’s vital energy exports and trigger fuel shortages across the country.