Hungary and Romania have cut nuclear power output as record-low river levels disrupted shipping and supply chains
The disastrous heatwave and drought across Europe have pushed the Rhine and Danube rivers to historic water lows, forcing two EU countries into atomic energy power-downs while disrupting industrial output and major trade routes.
The Rhine and Danube serve as vital commercial corridors, historic borders and a continuous navigable link between the North Sea and the Black Sea. Many European power plants rely on the rivers for cooling water, and that is why record-low levels have sharply reduced electricity output.
Hungary faces ‘unprecedented’ energy crunch
The Danube, which flows through or borders ten countries from southwestern Germany to the Black Sea, has reached historically low levels this July. In Budapest, the river fell to a record-low of 23 cm on Thursday, 10 cm below the previous record set in 2018, according to Hungary’s official water-monitoring service.
Hungary’s Paks nuclear plant, the country’s largest source of domestic power, generating nearly half of its electricity, was forced to cut output at three of its four reactors, reducing production to about 60% of capacity. On Thursday, Hungarian Prime Minister Peter Magyar warned the plant could be shut down altogether within 24 to 72 hours “for the first time in 44 years,” because its cooling-water intake nozzles can no longer reach the receding Danube.
“An energy crisis situation may arise from Monday,” Magyar warned, urging the public to reduce electricity use. He stressed the national energy supply remains secure for now, but warned that in the coming days “this unprecedented situation will require solutions we have not had to use before.” The government is preparing a series of measures, including mobilizing domestic generating reserves, securing electricity imports, asking major industrial consumers to reschedule production and voluntarily cut consumption, and reducing unnecessary energy use in government buildings.
Heatwave spreads across Europe’s nuclear sector
Downstream in Romania, one of two reactors at the Cernavoda nuclear plant – which generates roughly one-fifth of the country’s electricity – was shut down earlier this week because of low water levels. The Energy Ministry had planned to take the second reactor offline on Thursday due to “unfavorable developments in hydraulic conditions,” but kept it running overnight. It remains on standby for shutdown if river conditions deteriorate further, operator Nuclearelectrica said. The two reactors have never before faced simultaneous shutdown because of low water levels.
Analysts warn the reactor outages could increase Hungary’s and Romania’s reliance on electricity imports while driving up power prices across the EU, as both countries are normally major electricity exporters. The disruption could further deepen the bloc’s energy crunch, which began with the loss of cheap Russian gas following Ukraine-related sanctions on Moscow and has worsened this year amid the US war on Iran and the de facto closure of the Strait of Hormuz, a key global energy shipping route.
Meanwhile, Bulgaria is also on the brink of a severe grid emergency. Energy Minister Iva Petrova warned this week the country could be forced to temporarily shut down both operational reactors at the Kozloduy nuclear plant – its only nuclear power station – within days.
Elsewhere, French power providers are also feeling the strain of extreme heat. State-owned utility EDF shut down one reactor at the Golfech plant on Thursday after soaring river temperatures pushed cooling conditions beyond operating limits, and warned output at the Tricastin plant could also be reduced. Many of France’s reactors rely on river water for cooling, but environmental rules limit the discharge of heated water when river temperatures are already high. The outages have tightened electricity supplies, with French evening power prices climbing to around €200 per megawatt-hour on Thursday – among the highest summer levels since the 2022 energy crisis, according to Epex Spot data.
Switzerland’s Beznau plant on the Aare River has also been hit hard, with its two reactors cycling between full shutdowns and 50% power cuts over the past month after river temperatures reached the 25°C regulatory threshold.
Low water levels hit river traffic
Record-low river levels have also disrupted river traffic across Europe, affecting everything from shipping to tourist cruises. Cargo ships can no longer carry full loads, forcing operators to split shipments between several vessels or shift freight to road and rail, with surcharges driving up transport costs.
In Hungary, the Ministry of Transport and Investment said low water levels have halted most cargo traffic, with vessels still operating restricted to just 10% to 20% of their normal loads. Romania faces similar problems, with commercial barges barred from carrying full loads, while tugboats are limited to two barges per convoy, forcing multiple extra trips.
In Serbia, hundreds of small boats and dozens of cargo vessels have been stranded on the dried-out riverbank near Novi Sad, where the Danube has retreated up to 20 meters from its usual shoreline. Barges and tankers were carrying only about 30% to 40% of their normal capacity, local reports said. Serbia’s fuel imports plunged to just 25% of their July target because of constrained river transport, Serbian Mining and Energy Minister Dubravka Dedovic Handanovic said last week.
The Rhine traffic also affected
The Rhine flows about 1,230 km (765 miles) from the Swiss Alps through or along Switzerland, Liechtenstein, Austria, Germany, France and the Netherlands before reaching the North Sea, making it one of Europe’s busiest shipping routes for grains, minerals, ores, coal and oil products, including gasoline. Navigable depth at Kaub – a key Rhine chokepoint for shipments to southern Germany and Switzerland – stood at 29 cm on Thursday, the lowest since 2018, according to German federal data.
Cargo vessels continue to pass through the chokepoint but are carrying only about 20% of their normal loads, Roberto Spranzi, director of German shipping cooperative DTG, which operates around 100 inland freight vessels, told Reuters. He said low water levels mean four to five times more vessels are needed to move the same volume of cargo. As a result, tanker barge transport from Rotterdam to Karlsruhe, Germany, rose to around €145-€150 ($165.84-$171.56) per ton on Thursday from €45 at the end of June, according to media reports citing commodity traders.
Reduced navigable depths are disrupting deliveries of essential petrochemical feedstocks, including naphtha and liquefied petroleum gas (LPG), reports claim. Commodity intelligence provider ICIS reported that LyondellBasell had declared force majeure on butadiene supplies from its Wesseling plant after low water levels disrupted feedstock deliveries. German chemical giant BASF also warned of possible force majeures and product shortages because it relies heavily on the river for transport.
Heavy industry along the Rhine is also feeling the impact. German steelmaker Thyssenkrupp said this week the severe drought has created major bottlenecks in transporting raw materials to its main production hub in Duisburg, forcing it to curb hot metal production.
Forecasts show Rhine clearance could fall to 24 cm on Friday, the lowest level since records began in 1990, which could worsen the bottlenecks and further drive up shipping costs.
Meanwhile, another major heatwave – the fourth this summer – is forecast to hit Western Europe in the coming days, meteorologists warn. Temperatures are expected to soar above 40°C across the Iberian Peninsula and France, with some areas potentially reaching 45°C. As the system moves east, 40°C-plus heat is forecast to spread across Central Europe, from western Germany to Italy, Hungary and much of the northern Balkans.
