Record-Low Danube Levels Trigger Energy Emergency Across Central Europe

Cernavodă nuclear plant (Romania). Unit 1 was shut down in a controlled manner on July 28 because the Danube's flow was too low for cooling . Unit 2 followed on July 29 — the first time both reactors had ever been offline simultaneously due to low water . The plant typically supplies about 20% of Romania's electricity.

Paks nuclear plant (Hungary). Hungary's only nuclear plant cut output by roughly 50% at one reactor starting July 29 . By July 30–31, Prime Minister Péter Magyar warned the entire plant could shut down for the first time in its history because suction nozzles could no longer reach the river's cooling water . He said the plant might stay offline for weeks as the river was expected to keep receding .

River transport. Barges in Serbia were left stranded in receding waters, with some stretches shallow enough to cross on foot . Freight traffic on one of Europe's key waterways was severely disrupted, and river cruises were forced to alter routes .

Broader power supply impacts. Romania's state of alert allows the government to allocate funds for emergency power purchases and manage grid restrictions . Hungary began preparing plans for large industrial users to cut consumption . Both countries faced reduced hydropower output alongside the nuclear shortfalls, compounding the supply gap .

Why this is a climate-driven vulnerability

This event is not an isolated anomaly. A prolonged heatwave and months of below-average rainfall across Central and Eastern Europe pushed the Danube to historic lows simultaneously in multiple nations . Because nuclear plants are typically sited on large rivers for cooling, they are directly exposed to drought risk — a vulnerability that climate models project will worsen with more frequent and intense dry spells. The crisis affected at least four countries (Romania, Hungary, Serbia, Croatia) across electricity generation, river freight, irrigation, and tourism, demonstrating how a single hydrological shock can cascade through interdependent energy and transport systems .