AP

EXPLAINER: Power cuts raise risk at Ukraine nuclear plant

Oct 12, 2022, 10:57 AM | Updated: 3:18 pm

FILE - A view of the Zaporizhzhia Nuclear Power Station, in Enerhodar, Zaporizhzhia region, in terr...

FILE - A view of the Zaporizhzhia Nuclear Power Station, in Enerhodar, Zaporizhzhia region, in territory under Russian military control, southeastern Ukraine, on May 1, 2022. The plant, that has been surrounded by Russian forces, lost power Wednesday morning, Oct. 12, 2022, when a Russian missile damaged a distant electrical substation, increasing the risk of radiation disaster, according to the plant's operator. (AP Photo/File)

(AP Photo/File)

BERLIN (AP) — A Ukrainian nuclear power plant that has been surrounded by Russian forces lost power Wednesday morning when a Russian missile damaged a distant electrical substation, increasing the risk of radiation disaster, according to the plant’s operator.

The power to Zaporizhzhia Nuclear Power Plant was restored about eight hours later, the International Atomic Energy Agency said. But experts say the outage — the second one in five days — shows just how precarious the situation at Europe’s largest nuclear plant is. They say repeated power outages over short periods of time are only making the problem worse.

Here’s a look at the risks:

DISASTER DANGER

Fears of a nuclear catastrophe have been at the forefront since Russian troops occupied the plant during the early days of the war. Continued fighting between Russian and Ukrainian forces — as well as the tense supply situation at the plant — have raised the specter of a disaster.

Ukrainian authorities decided several weeks ago to power down the last reactor to reduce the risk of a catastrophe like the one at Chernobyl in 1986, where a reactor exploded and blew deadly radiation across a large vast area.

But the reactor core and used nuclear fuel must still be cooled for lengthy periods to prevent them overheating and triggering dangerous meltdowns like the ones that occurred in 2011 when a tsunami hit the Fukushima plant in Japan.

IODINE SUPPLIES

Some European countries are trying to prepare for the worst and started stockpiling iodine tablets to help protect their populations from possible radioactive fallout.

In others, like Germany, authorities have calculated there is a low risk that radiation levels harmful to human health would reach their territory.

In the event of a disaster, the biggest risk outside Ukraine could be to Russia, “depending on which way the wind blows,” said Paul Dorfman, a nuclear expert at the University of Sussex in England.

“The main deposit is likely to be in Ukraine and or Russia, but there could be significant radiation pollution in Central Europe, which is why countries around Ukraine are now thinking very seriously about issuing stable potassium iodide tablets,” he said.

LIMITED POWER SUPPLY

The Zaporizhzhia plant has been receiving external power to ensure the important task of cooling the reactor and spent nuclear fuel can continue, but the connections are at constant risk of disruption due to the conflict.

As power lines and substations have been damaged in fighting, Ukraine’s nuclear operator Energoatom has been forced to repeatedly rely on diesel generators. These generators, which have enough fuel for at least 10 days, have kicked into action when external power has failed — but experts say their repeated use over a short period of time increases the risk of a disaster.

“There are several redundancies and the facilities are now repeatedly on the last one,” said Mareike Rueffer, head of the nuclear safety department at Germany’s Office for the Safety of Nuclear Waste Management.

“Having to repeatedly fall back on diesel generators also limits the room for maneuver,” she added. “In that moment there’s no further backup and this is a high-risk technology.”

The diesel generators kicked in immediately Wednesday when electricity from the missile-damaged substation was cut. External power from the transmission line was restored hours later.

ONGOING RISK

Shutting down the plant’s last reactor several weeks ago significantly reduced the risk of a radiation disaster by gradually increasing the time it would take for a meltdown to occur. But if cooling fails due to a complete loss of power, meltdowns would still happen eventually, said Rueffer.

Dorfman said that in the worst case, Ukraine could see a situation similar to what happened in Fukushima.

“You’d see a heating of the high level spent fuel ponds. You’d see a hydrogen explosion, as we saw in Fukushima,” he told The Associated Press. “And then you’d see a significant radiation release.”

___

Associated Press writer David Keyton contributed from Stockholm.

Copyright © The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

AP

Speaker of the House Mike Johnson...

Associated Press

House Speaker Mike Johnson says he will push for aid to Israel and Ukraine this week

House Speaker Mike Johnson said Sunday he will try to advance wartime aid for Israel this week, along with funding for Ukraine.

55 minutes ago

President Joe Biden speaks at a campaign rally Saturday, March 9, 2024, at Pullman Yards in Atlanta...

Associated Press

US shoots down ‘nearly all’ Iran-launched attack drones as Biden vows support for Israel’s defense

Joe Biden cut short a weekend stay at his beach house to meet with his national security team as Iran launched an attack against Israel.

1 day ago

Protesters in Phoenix shout as they join thousands marching around the Arizona state Capitol after ...

Associated Press

Abortion ruling supercharges Arizona to be an especially important swing state

A ruling this week instituting a near-total abortion ban supercharged Arizona's role, turning it into the most critical battleground.

2 days ago

Former President Donald Trump, center, appears in court for his arraignment, Tuesday, April 4, 2023...

Associated Press

Manhattan court searching for jurors to hear first-ever criminal case against a former president

Jury selection is set to start Monday in former President Donald Trump's hush money case — the first trial of the presumptive nominee.

2 days ago

Emergency personnel arrive on the scene after a  an 18-wheeler crashed into the Texas Department of...

Associated Press

1 dead and 13 injured in semitrailer crash at a Texas public safety office, with the driver jailed

A driver rammed an 18-wheeler though the front of a building where his renewal for a commercial driver’s license had been rejected.

2 days ago

Republican presidential candidate former President Donald Trump speaks at a Get Out The Vote rally ...

Associated Press

Trump pushes Arizona lawmakers to ‘remedy’ state abortion ruling that he says ‘went too far’

Donald Trump urged Arizona lawmakers on Friday to swiftly “remedy” the state court ruling allowing prosecutors to enforce an abortion ban.

2 days ago

Sponsored Articles

...

Midwestern University

Midwestern University Clinics: transforming health care in the valley

Midwestern University, long a fixture of comprehensive health care education in the West Valley, is also a recognized leader in community health care.

...

Collins Comfort Masters

Avoid a potential emergency and get your home’s heating and furnace safety checked

With the weather getting colder throughout the Valley, the best time to make sure your heating is all up to date is now. 

(KTAR News Graphic)...

Boys & Girls Clubs

KTAR launches online holiday auction benefitting Boys & Girls Clubs of the Valley

KTAR is teaming up with The Boys & Girls Clubs of the Valley for a holiday auction benefitting thousands of Valley kids.

EXPLAINER: Power cuts raise risk at Ukraine nuclear plant