A river fell below the level at which it can cool a nuclear plant, and up to 2,000 megawatts began coming off a national grid in the middle of a heatwave. The chain from drought to switchgear is rarely this short, and almost never this well documented.
Paks, Hungary's only nuclear station, sits around 90 kilometres south of Budapest and draws Danube water to cool its four Soviet-built reactors [2]. By Friday it was producing 965 megawatts rather than the usual 2,000 [2]. The Associated Press reported that the level at Paks could recede to negative 144 centimetres, far below the previous record of negative 98 centimetres set in 2018, and that a reading of negative 134 centimetres requires the full powering down of the plant [2]. Euronews gave a different measure earlier in the week, a Danube gauge level of 23 centimetres on Wednesday, without naming the station [3]. Readings on the Danube are taken against local reference points, and those two numbers should not be set against each other.
We reported on Friday that the plant had stopped completely, in a piece that also said its output would leave the grid on Monday. Those two statements cannot both be true, and the second one is the better supported of the pair. What the record supports is a plant coming down, not a plant already down. The correction is ours.
Whether the plant is already off is where the record splits. The Associated Press reported on Friday morning that further reductions were imminent later that day and that the entire plant would likely be powered down by Tuesday or Wednesday [2]. Euronews reported the same day that Paks "was taken offline" and described it as the first complete shutdown in the plant's history [1]. A day earlier, Euronews had written that the plant "has never previously shut down entirely" and quoted Prime Minister Peter Magyar saying "It seems, at this point, that the complete shutdown of the Paks power plant could take place today, or perhaps tomorrow" [3]. Those accounts are not reconcilable as written. This piece does not resolve them.
The plant's age is unsettled too. Euronews wrote that this is the first shutdown "since it opened 42 years ago," attributing the figure to nobody [1]. The Associated Press wrote that a shutdown would be the first "in its 44 years of service" [2]. Two years is not a rounding error on a claim doing this much rhetorical work.
The share of Hungarian electricity at stake needs the same care. Magyar said: "This means 2,000 megawatts will be lost from Hungarian energy production from Monday at the latest, while demand for residential and public consumption continues to rise because of the heat" [1]. Andras Perger, an expert at the Hungarian NGO Energiaklub, put the loss at 25 to 30 percent of energy output [1]. Both Euronews and the Associated Press separately describe Paks as supplying nearly half of Hungary's electricity production [2][3].
Those two shares cannot be describing the same denominator. If 2,000 megawatts is 25 to 30 percent of the total, the total is somewhere between roughly 6,700 and 8,000 megawatts. If the same 2,000 megawatts is nearly half, the total is closer to 4,000 to 4,500. The most likely reading is that the near-half figure describes domestic generation while Perger's quarter-to-third describes total supply including imports, and the gap between them is roughly what Hungary buys from its neighbours. Neither source says this. Readers should take the 25 to 30 percent as Perger's estimate of the hit to supply, and the near-half as a description of what Paks contributes to generation, rather than treating them as rival measurements of one number.
The response is running entirely on the demand side, because no supply-side answer is available this week. The government asked the public and businesses to cut consumption during peak hours between 5pm and 10pm, singling out air conditioning and washing machines [1]. Large industrial users were asked to cut voluntarily, and the Associated Press reported that the energy conglomerate MOL committed to reducing its electricity needs by 65 megawatt-hours, a decrease of 40 percent from normal consumption [2]. State institutions were told to switch off decorative lighting by Monday, and parliamentary sessions were suspended to conserve energy [2]. Magyar asked large consumers and the public alike to "act responsibly" in what he called an "unprecedented situation" [1].
The European Commission's answer came through Anna-Kaisa Itkonen [1]. "Although the operator has emergency measures in place to guarantee nuclear safety, an event of this kind could further strain the regional electricity balance. The Commission stands ready to convene an ad hoc meeting of the Electricity Coordination Group," she said [1].
The regional dimension is the part planners should sit with. Perger noted that some of Hungary's demand could be met through imports from neighbouring countries, though the availability of hydroelectric power is itself limited in the region [1]. The drought that pulled Paks off the grid is the same drought thinning the hydro that would ordinarily backfill it. A cooling intake and a run-of-river turbine fail for one reason, at one time, across one watershed, which is what makes this a regional balance problem rather than a Hungarian one.
Hungary has throttled Paks before. Euronews noted the plant has repeatedly had to reduce output in summer because of high water temperatures and low river levels [3]. What is new is a specific number: negative 134 centimetres, the gauge reading at which the cooling water is simply not there, against a forecast that says the river is still going down [2].
