Ukraine War: Power Restored To Ukraine Nuclear Plant, Last Reactor Shut Down To Avoid Disaster

Power to a key nuclear power plant in Ukraine has been restored and the plant has returned to safe status — for now.

Concerns for Ukraine's Zaporizhzhia nuclear plant —the largest in Europe— remain as shelling and fighting in the area continues which risks damaging the plant and leading to a radiation disaster. Both the Ukrainians and the Russians accuse each-other of targeting the plant. 

Ever since external power to the plant was cut a week ago because of shelling, it was operating in "island mode" under which it was electricity for crucial cooling systems from its only remaining operational reactor. Such a method of operation is considered unstable as it could lead to damage to key equipment including turbines and pumps. After external power was restored, the plant's engineers shut down its last operational reactor to avoid such a risky situation.

The six-reactor Zaporizhzhia Nuclear Power Plant lost its outside source of power a week ago after all its power lines were disconnected because of shelling. 

Nuclear operator Energoatom said one of the power lines was restored “to its operational capacity” late Saturday, making it possible to run the plant's safety and other systems on electricity from the power system of Ukraine.

“Therefore, a decision was made to shut down power unit No. 6 and transfer it to the safest state – cold shutdown," the company said Sunday in a statement.

Energoatom said the risk remains high that outside power is cut again, in which case the plant would have to fire up emergency diesel generators to keep the reactors cool and prevent a nuclear meltdown. The company's chief told The Associated Press on Thursday that the plant only has diesel fuel for 10 days.

The plant, one of the 10 biggest atomic power stations in the world, has been occupied by Russian forces since early in the war, which marked its 200th day on Sunday. 

Energoatom renewed its appeal for Russian forces to leave the Zaporizhzhia plant and allow for the creation of a “demilitarized zone” around it.

The International Atomic Energy Agency (IAEA), the United Nations nuclear watchdog that has two experts at the plant, confirmed that external power has been restored there. However, IAEA Director-General Rafael Grossi said he remains “gravely concerned about the situation at the plant, which remains in danger as long as any shelling continues”, adding that “consultations have begun on the urgent need to establish a nuclear safety and security protection zone” at the plant.

The IAEA said it would take 30 hours to bring the sixth reactor to a “cold shutdown state” but it will still require electricity for its safety systems after that. The agency said work is under way to restore other power lines at the plant, which remains occupied by Russian forces but run by Ukrainian engineers.

Meanwhile in Eastern Ukraine, a stunning Ukrainian military push has forced the Russian soldiers to retreat. The Ukrainians have occupied key towns, including a key Russian logistics hub. The Russians have responded with long-range strikes on Ukrainian power stations, causing outages across the country.

(With AP inputs)