In order to divert the huge power generation to the Russian grids, the power plants must be first shut down properly and then re-started after the grid hardware is firmly re-established to an alternate line. This could be the reason that the Russian experts have been observed working that has unnerved the Ukrainians and rightly so. A news has come that the power plants have been shut down. If the shutdown has been made to connect the grid to Crimea/Russia, it will take a a longer time. It is also possible that Russia might have shut down to repair the existing damaged Ukrainian grid.
The news of shutdown has made the Ukrainian leadership very nervous. This has made the Ukrainians raise all sorts of hue and cries, crying foul to raise international concerns of impending nuclear blowout that happened in Fukushima. However, there is no similarity between the two. Fukushima blowout took place because the nuclear plant could not be shut down properly during the earthquake that also disrupted the cooling system of the plant. In the time left before the blowout, an alternate source of cooling could not have been created. That is why all personnel working at the site were evacuated in time as the meltdown was inevitable. This is not the case at Zaporizhia. Here all systems are working properly in a controlled way. The shutdown has stopped all ongoing nuclear fission reactions. The fission reaction will not restart unless manually initiated again by the controllers.
Various nuclear experts are expressing their opinions on this issue based on their compulsions of affiliations and integrities. European experts speak of the risk or at least possibility of a meltdown even if tangentially, following a proper shutting down of the reactors in the present situation, that is surely not the case. Any independent nuclear scientist / expert will negate or dismiss such possibilities. However, huge financial consequences are at stake in the process and hence, Ukraine is trying all means at its hands to raise red flag, whether just or otherwise. If Russia is able to undertake the grid diversion soon, Ukraine will have no option but to regret losing its control. It is also possible that Russia might have actually shut down the reactor for rectifying the power grid damaged by the missiles/explosives. In that case, it would go critical in a day or two. It must not be assumed that they will not try to connect their Crimea/Russia grid in future if it remains under their control.
Ukraine has been trying to get the control of Zaporizhia in own hands and that may not happen for two reasons. Firstly, Russia will like to thwart Zelensky's ambition of producing nuclear weapons (that he once expressed before the outbreak of the war). Secondly, this gives Russia an immense scope for owning huge electrical energy. It can also be assumed that Russia will not give their military control over the plant. They will surely try arm twisting measures on Ukraine. On the other hand, losing the Zaporizhia nuclear power plant that altogether can generate as much as 5700 megawatts, will be economically crippling on Ukraine. Stakes are surely very high esp for them.
Russia has agreed to UN suggestions of allowing IAEA inspection. It must be understood that the IAEA mandate is only towards "peaceful use of nuclear energy" maintaining transparency on the non-proliferation and safety of nuclear fuel. This must be the case for sure at Zaporizhia otherwise Russia would not have agreed for it in the first place. On the other hand, Ukraine/EU/NATO is believed to be trying to insert additional clauses in the IAEA mandate including 'safety and security of the plant' and some more. Those additional clauses may not be agreeable to the Russians. Another point of contention has been whether the inspectors should come through Ukraine or Russia. It may be of no consequence whether these IAEA experts come through the Russian side or Ukrainian, unless Ukraine intends to play a high risk game of sending troops/spies in their shadows.
Just before the publication of this article on 01 Sep 22, it is believed that the IAEA team has not found anything drastically wrong and most of the inspectors have returned back with a few left behind. It seems that despite Zelensky's briefing, IAEA has gone professionally in their approach not succumbing to Ukrainian pressure and agenda. This will surely disappoint or infuriate Zelensky. Clearly, their tactics have not paid off. Zelensky/EU/NATO will have to try something else in the coming days/weeks.
With the Zaporizhia nuclear power plant gone into the Russian hands, Ukraine is going to pay a very heavy price for President Zelensky’s blitzkriegs in terms of loss of lives, territories and huge infrastructures. It is sad that the UNSC is defunct, witnessing all these unfortunate events helplessly.