The Risks of Zaporizhzhia Being Disconnected From Ukraine's Grid

Zaporizhzhia, Europe's largest nuclear power plant, remained disconnected from Ukraine's electricity grid on Friday morning, Ukrainian nuclear operator Energoatom said.

A day after the power plant at Zaporizhzhia in southern Ukraine went offline in a historic first, allegedly caused by nearby fires, Energoatom issued a statement saying that all six of its reactors were still disconnected from Ukraine's electricity grid as of 9 a.m. local time.

Russia, meanwhile, has pushed back by saying that the Zaporizhzhia nuclear plant is operating normally, and that there was no complete shutdown.

The nuclear plant has been under Russian control since March 1, just days after Russian President Vladimir Putin's invasion began. It was one of the first sites to be seized by Russian forces, but it is still run by Ukrainian staff.

There have been widespread concerns about a potential nuclear catastrophe as the plant, which is located near the front line in the city of Enerhodar, has remained a target of shelling in recent weeks. Both Ukraine and Russia have accused each other's forces of shelling the plant.

Experts have also raised concerns about the consequences of the plant being disconnected from the Ukrainian grid, while Washington has cautioned against diverting power from the site to occupied areas.

Prior to the war, the nuclear plant supplied more than a fifth of Ukraine's electricity needs, and its loss would mean further strain as the country prepares for what President Volodymyr Zelensky has warned could be the most difficult winter in the country's history due to high fuel costs and "Russia's aggression."

International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi stressed Thursday that there is a new incident at or near the Zaporizhzhia nuclear power plant almost every day. "We can't afford to lose any more time," he said in a statement.

On Thursday a bipartisan group of former U.S. nuclear safety officials addressed a letter to U.S. President Joe Biden urging him to push for an IAEA inspection of the Zaporizhzhia nuclear power plant.

On the same day the White House also called on Russia to agree to a demilitarized zone around the nuclear plant.

"Weaponizing Winter"

John Erath, senior policy director for the U.S.-based nonprofit Center for Arms Control and Non-Proliferation, told Newsweek that disconnecting the Zaporizhzhia plane from the Ukrainian power grid could have dire consequences for the country.

"This would deprive Ukraine of up to 20 percent of its electricity. Winter is coming. Thousands of civilians could be in danger of starving or freezing. Unable to achieve its goals on the battlefield, Russia may be weaponizing winter," Erath said.

On Thursday Washington accused Moscow of attempting to "create energy crises in Europe."

"No country should turn a nuclear power plant into an active war zone, and we oppose any Russian efforts to weaponize or divert energy from the plant," State Department spokesperson Vedant Patel told reporters. "To be very clear, the [plant] and the electricity that it produces rightly belongs to Ukraine, and any attempt to disconnect the plant from the Ukrainian power grid and redirect to occupied areas is unacceptable."

Cooling Failure

Disconnecting the nuclear plant from the Ukrainian grid presents a potential risk as should backup power systems fail, fuel in the reactor core could melt.

Petro Kotin, the head of Energoatom, Ukraine's atomic energy company, told The Guardian that disconnecting the plant entirely would would raise the risk of a catastrophic failure as it would be left dependent on a single source of electricity to cool its active reactor.

"You cannot just switch from one system to another immediately, you have to... shut down everything on one side, and then you start to switch on another side," Kotin said.

If a power link fails, back-up diesel-powered generators kick in, providing electricity for as long as there is fuel. Kotin said reactors would reach a dangerous temperature after just 90 minutes.

"During this disconnection, the plant won't be connected to any power supply and that is the reason for the danger," Kotin said. "If you fail to provide cooling... for one hour and a half, then you will have melting already."

Ed Lyman, director of nuclear power safety with the Union of Concerned Scientists, said the ongoing situation is "fragile," and that without knowing the actual situation at the plant: "I can't have any confidence in the reliability or the duration of the backup power supplies."

Newsweek has reached out to Energoatom and Russian authorities for comment.