The Zaporizhzhia nuclear power plant in Ukraine came under the control of Russian troops less than a week after the start of the Russian invasion of Ukraine. Its takeover went relatively smoothly, but by early March the facility was already the target of shelling. This is still going on at a much higher intensity today, with the plant demonstrably being used by the Russian side for ammunition storage and as an (artillery) firing position. The ongoing crisis thus points to the serious possibility of an accident or Russian use of the plant as a kind of strategic weapon in order to put pressure on Kyiv and its Western allies.
The Zaporizhzhia plant is built of massive reinforced concrete construction and contains six water-cooled and moderated VVER-1000 type power pressurized water reactors, each with a capacity of 950MW, making it not only the largest power plant in Ukraine but also the largest in Europe and the fifth largest in the world. Water from the Kakhovka dam on the Dnieper is used for cooling. The structure itself is designed to withstand extreme external events such as an aircraft impact or explosion and should thus be largely immune to shelling.
In particular, a potential risk is damage and subsequent failure of external systems supplying electrical power to the nuclear reactor cooling systems, and several of these sources have already been damaged. Ukraine’s nuclear agency Energoatom said that Russian forces were trying to access the diesel fuel supplies that would be needed for the alternators to operate in the event of a power outage. Continued combat activity around the plant could thus fundamentally jeopardise its functionality. The biggest problem is considered to be the rapid overheating and the possible meltdown of the reactor once the zirconium cladding begins to release hydrogen and the possible spread of radioactive material.
Concern has been expressed in this regard by the European Union, which, in the words of Commissioner Simson, states “The EU reaffirms that the deployment of Russian military personnel and weaponry at the Zaporizhzhia nuclear facility is an open violation of all internationally agreed safety, security and safeguards provisions”. Russia, however, rejects the proposals to demilitarise the nuclear facility.
In addition to the damage caused by shelling, Russia’s use of the nuclear power plant as an instrument of coercion in order to make political concessions in Ukraine is a possible risk. Given that the Russian forces are unable to continue their offensive efforts in the long term without additional mobilisation, they need to stabilise the situation. The Russian occupation administration wants to hold a referendum on the annexation of the so-called ‘Kherson region’ to Russia, in which case it would very likely connect the power plant to its own grid.
However, the situation may be considerably complicated by the announced Ukrainian counter-offensive on the Russian bridgehead on the right bank of the Dnieper, where a significant number of Russian forces may be surrounded.
To break, or at least limit, Ukraine’s resolve to fight on and intimidate Western states from continuing to assist, Russia may use a controlled nuclear accident. Red lines signalized by NATO states that could trigger a direct response include the unacceptableness of the use of weapons of mass destruction (chemical, biological and nuclear). In this case, a controlled accident will create the possibility of making pressure on the political leadership of Ukraine and Western states, but it is difficult to verify as a clear military use and is, therefore, a move under the bar of direct escalation in form of reciprocal violence in terms of state behaviour. The effect of such an accident would thus exhibit similar characteristics to the use of other weapons of mass destruction in that it would at least indirectly and secondarily affect population centres. From this perspective, Russian forces are using the plant as an active threat to pro-Ukrainian states before providing more substantial support, given that the bars of mutual escalation are still relatively low and stable. Keeping the area under control until the referendum is declared will then allow Russia to extend its strategic nuclear deterrent to the new territories, as in the case of Crimea, and to normalise and stabilise the situation from their point of view. It seems at least the Ukrainian side takes this scenario and threat seriously, as indicated by the statement of President Zelensky, where he has accused Russia of using “nuclear blackmail”. Moreover, the Ukrainian and Russian sides actively accuse each other of planning to create a (nuclear) incident at the plant in the form of a false flag operation, and according to reports from August 20, the occupation administration ordered most of the employees to leave the plant.
