The Zaporizhia NPP (ZNPP) is still without external power after it was disconnected from its last remaining 750kV external main power line was on 23 September. It lost the connection to its last 330 kV back-up power line in May. Both lines come through Ukrainian controlled territory. Following this power loss, emergency diesel generators (EDGs) immediately began operating to supply the plant with power.
According to the International Atomic Energy Agency, the power line was damaged around 1.5 kilometres from Zaporizhia due to military activities. The IAEA team based at ZNPP has not yet been able to visit the damaged line due to the military situation. ZNPP said it has the necessary spare parts and personnel to repair the line once the military situation permits. Ukraine reportedly told IAEA that it is also prepared to repair damage to the back-up power line, when the military situation permits.
Immediately after disconnection of the 750 kV line, all 18 of the available emergency diesel generators started operating but ZNPP gradually reduced the number to only those needed to generate essential power for the site – currently seven – to help save diesel fuel. ZNPP has previously informed the IAEA that it has fuel reserves for almost 20 days operation of its emergency diesel generators. The plant regularly receives supplies of diesel fuel to maintain its inventory.
Radiation monitoring stations positioned on as well as outside the Zaporizhia site showed that all radiation levels remained normal. In addition, the IAEA team has carried out independent monitoring within the site perimeter, which confirmed these results.
Responding to a widely quoted article in the UK Guardian, which suggested that extended power loss could lead to a core melt-down similar to Fukushima, Russian experts have explained that this is not possible.
Yevgeniya Yashina, Zaporizhia NPP’s Director of Communications explained to TASS that all the plant’s reactors are in cold shutdown. “This means that the nuclear fuel inside them is not hot, but has cooled to a safe temperature, like very hot tap water. It simply cannot overheat quickly,” she said. In addition, despite the interruptions in external power supply, all systems necessary for the operation of the plant, including continuous cooling of nuclear fuel, are powered by backup energy sources. She emphasised that there is enough diesel fuel to “operate the generators for a long time in standalone mode”.
She added: “We have two key safety factors: the absence of a strong heat source and the proper functioning of backup power systems, which completely eliminates the possibility of a Fukushima-style accident.”
Business FM spoke with Vladislav, a ZNPP employee who said the situation at the plant is calm, there is enough fuel, and there are other solutions to support backup power:
“There is enough fuel for the station to operate safely. People are not panicking. Everyone is doing their job. There is no evacuation. Everything is quite calm. Fuel is being supplied continuously, especially since there are storage reserves on site. It is true that diesel generators cannot operate for long periods in this mode. However, there are also mobile diesel generators available, so they will be used as a last resort. I believe that a solution will be found.”
Zaporizhia Director Yuriy Chernichuk said the station has enough fuel to operate the diesel generators for an extended period. “The limits of safe operation conditions at the moment, in these operating conditions of the station are being observed. The staff are at their workplaces…. The operating mode is far from normal, but it is fully controlled by the staff, and we currently perform safety functions, provide them, and see no reason for panic and concern,” he noted
He added that the employees are promptly carrying out any necessary equipment repairs and, if possible, are working to restore the damaged power line. According to the ZNPP press service, the cooling functions of nuclear fuel in the holding pools and reactors are being performed in full.
