Danube Water Rise Revives Paks Plant But SE Europe Power Stress Endures
Hungary's nuclear restart offers partial relief, but analysts warn drought-driven capacity losses across Romania, Austria and Slovenia could persist well into autumn.
Hungary's Paks nuclear plant was expected to resume generating electricity as early as Monday evening (2026-08-10) after rising Danube water levels allowed operators to switch on one of its turbines, Prime Minister Peter Magyar said — the first step towards restoring a unit that normally supplies more than 40% of the country's electricity.6,5
The Danube had been falling so fast that a forced complete shutdown of Paks looked possible before the trend turned. Water levels stopped dropping and began recovering in time for Hungary to avoid that outcome, according to OilPrice.com reporting. But the improvement has not dissolved the broader regional pressure.5,6
Austrian day-ahead power settled at €150.10/MWh on Tuesday (2026-08-11), while Romanian day-ahead stood at €152.64/MWh in the same session — both reflecting persistent supply shortfalls and the cost of drawing on imports from less-stressed markets outside the region. [live prices]
Paks alone does not explain those prices. Montel reported on Friday (2026-08-07) that record-low Danube water levels had simultaneously cut nuclear generation in Hungary, Romania and Slovenia, leaving roughly 42% of southeast Europe's nuclear capacity affected. When three countries lose generation at once, interconnector flows that normally redistribute stress cannot fully compensate; all three become importers simultaneously.4
The drought extends beyond the river. Montel EQ analyst Eylert Ellefsen said on Thursday (2026-07-30) that hydropower inflows in the Alpine region were "close to an all-time low," with no short-term recovery in sight. Inflows to reservoirs and run-of-river plants covering Austria and Switzerland were running nearly 50% below average, according to Montel EQ data. Austria generates a substantial share of its power from Alpine hydro; near record-low inflows mean that generation cannot replace what the Danube basin has lost.2
Standard Chartered commodity analysts noted that extreme heat and drought are now impairing Europe's energy system across several vectors simultaneously — river levels forcing cuts to nuclear output, hydroelectric generation falling, and cooling efficiency losses at thermal plants adding to fuel consumption. When hydro is short, thermal plants must run harder, and heatwaves degrade the very cooling systems those plants depend on.3
Romania has carried additional weight this season. Cernavoda nuclear plant lost 1.3 GW of stable capacity when a faulty transformer shut down the 650 MW Unit 2 in May (2026-05-18), coinciding with scheduled maintenance on the 650 MW Unit 1 that had begun on 10 May 2026. Analysts told Montel at the time that the outages pushed Romania's electricity system "to its limits" and produced significant morning and evening price spikes. Those events were separate from the current Danube-driven cuts, but they left Romania entering summer with less buffer than usual.1
Analysts told Montel on Friday (2026-08-07) that southeast Europe must sharply accelerate investment in storage, flexible generation, grid upgrades and demand response to prevent this summer's crisis from repeating. None of that investment will materialise in time to ease this season's constraints.4
The immediate trajectory depends on rainfall and inflow recovery in the Alpine watersheds. Ellefsen saw no short-term relief as of Thursday (2026-07-30), and with summer temperatures still elevated, autumn rains remain the first plausible turning point. Reservoir refill after a near-record-low inflow season takes weeks, not days. Austrian and Romanian day-ahead prices are unlikely to ease significantly before hydro inflows recover and affected nuclear units return fully to service — neither of which carries a firm date.2,4