Hungary is switching off the Paks nuclear power plant, the source of roughly half the country's electricity, for the first time in its 44 years of operation, because the Danube is running too low to cool it [1][2].
The wind-down is proceeding by blocs. Reactor 3 shut down on Friday, taking the plant to about 48 percent of normal output, 965 megawatts of a 2,000 megawatt capacity [2]. A second bloc followed on Saturday, cutting output to roughly a quarter [2]. Prime Minister Peter Magyar said on Friday that further reductions were imminent; in the words of the ABC News wire account of his remarks, "the entire plant will likely be powered down by Tuesday or Wednesday" [2]. Tuesday or Wednesday is August 4 or 5.
The cause is not in the machinery. The Danube gauge at Paks fell to 23 centimetres on Wednesday, and forecasts have the river potentially falling to minus 144 centimetres, far below the record low of minus 98 set in 2018 [1]. No significant rainfall is forecast [1]. Reactor cooling at Paks depends on river water, and a river at record lows in a heatwave cannot supply it [1].
Hungary is not alone on this. Romania shut down both of its reactors on July 29 for the same reason [2]. Between the two countries, four reactors have come offline in a week for want of cooling water, with Paks's remaining blocs scheduled to follow within days [1][2].
What Hungary does for electricity while Paks is dark is not answered in the verified record. The plant normally supplies about half the country's power [1]. The shutdown arrives in the middle of the same heatwave and drought that lowered the river [1].
None of the reactors coming offline has failed. The first full shutdown in Paks's 44 years is a hydrological event, not a mechanical one: the machines are sound, and the river they depend on is forecast to fall 46 centimetres below the lowest level ever recorded [1].
