Lessons from Zaporizhzhia

The Ukrainian nuclear power plant at Zaporižžja, on the banks of the Dnepr river, is the largest in Europe and the ninth largest in the world: six reactors with a total of 5700 MW.

Over the past 18 months, there have been several alarms about the safety status of the plant, in which thousands of Ukrainians work, under the control of the Russian military and in the presence of International Atomic Energy Agency (IAEA) observers. Where do we stand?

A very difficult situation

The answer is sadly simple: we do not know precisely, for at least three reasons.

Nothing told by the two contenders about the situation in Zaporižžja is credible. Suffice it to say that, officially, we still know nothing about the serious attacks on two huge energy infrastructures such as the Nord Stream gas pipelines and the Kakhovka dam: a lot of propaganda from both sides, zero reliable evidence.

The situation is completely unprecedented: never has a nuclear power plant been on a battlefield. We are learning day by day, and unfortunately it is not a simulation.

At times, it has emerged that neither Russian nor Ukrainian commands have total control of the troops on the ground. This fuels the risk that the situation could get out of hand, beyond the will of the two governments. Perhaps this is a major concern of the IAEA Director General, who is making every effort to avoid the third energy disaster of this war.

The biggest concern: the intermittent supply of electricity

Paradoxical as it may seem, a nuclear power plant consumes large amounts of electricity. It is needed in particular for the operation of monitoring and safety systems, starting with the cooling systems. The ‘hot’ parts of the plant are the reactors themselves and the spent fuel rods, which continue to produce heat for years and must be immersed in special pools.

Under ordinary conditions, a nuclear power plant can self-produce the electricity it needs, but it is essential (all the more so in the theatre of war) that it is constantly connected to external high-voltage lines and also has ready - as an extreme emergency solution - diesel generators that can make up for the lack of electricity.

On several occasions in recent months, neither the full functionality of Zaporižžja's four external connection lines nor that of the auxiliary generators was guaranteed. Hence the constant alarms.

The current state

At the moment, the situation is less worrying than at the beginning of the conflict. Electricity production is at a standstill: the reactors are in a state of ‘cold shutdown’, in which cooling requirements are very low.

It is still possible to militarily attack the security of the plant by targeting the reactors (in robust concrete and steel containers) or the cooling pools (without similar protective structures). The damage scenario might be locally relevant, but it should not spread internationally as happened in Černobyl'.

What are the future prospects?

In the current military stalemate, neither of the contenders actually has an interest in damaging the plant: both know that, at the end of the conflict, it will be a key infrastructure for the region's economy.

The situation could change, however, if one of the belligerents sees defeat approaching: the Zaporižžja power plant can become a useful tool to inflict severe damage on the enemy in various ways.

However it will end, this story has something to teach us.

The real world - a less enchanting place than imagined by certain technocrats - is showing us that such a plant can be in the middle of a war dispute in which, at best, it can be used as a propaganda tool. At worst, however... well... we don't even want to think about it.

Nuclear power plants can never be proof against human error (Černobyl'), natural catastrophe (Fukushima) or human folly (Zaporižžja risk). How many more experimental tests do we need to realise that it is an inherently weak technology and totally unsuited to the unpredictability of the real world?