Ukraine nuclear power plant Zaporizhzhia on fire

[Rive]

Given the unstable situation I would think it would be wiser to just have all reactors shut down and cool off so that if anything happens they can be left.

Hard to tell from far. Nuclear reactors are reliant on offsite connection. If stopping the reactors makes the grid unstable/unavailable, then their decision to support the grid (and: themselves!) with just one reactor till the others cools down might be acceptable.
The other option is either to entirely rely on their diesels (in an unreliable/unknown fuel supply situation) or just hope that offsite power will be available.

From this far I can't tell.

 

[anorlunda]

war is war, better safe than sorry

In war you have risks versus risks. If the loose the power grid, most civilians and militia in Ukraine will loose all communications. No net. No TV. No radio. No phones. Also, in winter weather, freezing could make them lose all lights and most of the plumbing in buildings. Those things can be vital to keep the civilians alive in the midst of an invasion. Pre-war, 25% of Ukraine's power was nuclear.

Some headlines already speculate that the Russians could use conventional explosives to spread that radioactive material into the atmosphere. For that purpose, cold fuel is easier for them to work with than hot fuel. Just the threat might be enough for Russia to blackmail the NATO countries.

Headlines saying that a radioactive cloud is headed toward Western Europe would cause a panic. A small amount of radioactivity would be just as effective as a large amount for panic inducing effect.

 

[artis]

Some headlines already speculate that the Russians could use conventional explosives to spread that radioactive material into the atmosphere. For that purpose, cold fuel is easier for them to work with than hot fuel. Just the threat might be enough for Russia to blackmail the NATO countries.

Headlines saying that a radioactive cloud is headed toward Western Europe would cause a panic. A small amount of radioactivity would be just as effective as a large amount for panic inducing effect.

May I ask where do you read those headlines?

I just find it hard to believe than anyone could come up with something that crazy as to unload fuel from a reactor to make a dirty bomb, especially given Russia has any nuclear material on hand , everything from fresh uranium to used fuel to medical isotopes etc,

 

[anorlunda]

May I ask where do you read those headlines?

https://www.the-sun.com/news/4625415/russia-ukraine-dirty-nuclear-bomb-false-flag/

That is just one headline. I saw it first at: the headline aggregator:
https://www.drudgereport.com/
A site with 32 million visits per day.

But if you Google "dirty bomb" you'll find a long history of speculation about that scenario.

By the way, Russia could explode a dirty bomb from any territory under Russian control. It does not need to be Ukraine. All it needs is prevailing wind blowing away from Russia.

War is horrible. We must not fool ourselves into believing that the enemy will confine themselves to "civilized tactics" that we can imagine.

 

[Keith_McClary]

"civilized tactics"

Like bombing whole cities into rubble.

 

[gmax137]

it would be wiser to just have all reactors shut down and cool off so that if anything happens they can be left

this is not an option until the reactor has been shutdown for an extended time - active cooling is required for a few months at least.

 

[Keith_McClary]

March 2 - Russia tells IAEA it controls area around Zaporozhe plant​

https://world-nuclear-news.org/Articles/Russia-tells-IAEA-it-controls-area-around-Zaporozh

https://world-nuclear-news.org/Articles/Russia-tells-IAEA-it-controls-area-around-Zaporozh
Further down:

Director General Rafael Mariano Grossi ... said he thought Russian forces "are in control of the surrounding area and of the site as well. Which does not mean that they have taken over the plant itself, or the operation of the reactors. They have the physical control of the perimeter, including the village where most of the employees live."

After two days of controlling the surrounding area and the site, they needed to bombard the plant to take it over, so that the same staff could continue operating it.