Thanks again to Frances for alerting us to this.

From DW IN FOCUS, two days ago:

Romania has shut down its only nuclear plant in a rare move prompted by the lack of cooling water from the Danube River. Hungary, meanwhile, is racing to dam the Danube, trying to keep its Paks plant online. Romania shut down its lone nuclear power plant on Thursday, a rare move amid the drought that has caused record lows on the Danube River and other major waterways in Europe. 

The Danube is the sole source of cooling water for the Cernavoda plant, which usually generates around one-fifth of Romania’s electricity.  The power station has only been shut down once before, in 2023, again as a result of drought and a hot summer.

Meanwhile, Hungary was scrambling to dam the Danube, as it tries to keep its Paks nuclear power plant at least running at the minimal levels that it has maintained in recent days, which are far below capacity.

More at: https://www.dw.com/en/romania-shuts-nuclear-plant-hungary-dams-dry-danube-river/a-78359581

This is just the latest in developing tale of woe for nuclear power in this, not the last, heatwave/drounght:

Once more thanks to Frances McKie for alerting us to this video.

As the mighty Danube dries up in the heatwave, there are desperate measures to keep some goods flowing and enough water to cool power plants including nuclear ones. https://www.youtube.com/watch?v=uw–rQBsi8E

Reporting on the same events, the Guardian has:

Hungary has come “within millimetres” of having to shut down its nuclear power plant overnight, prime minister Péter Magyar said, as low water levels in the Danube continue to pose challenges for countries in south-eastern Europe. https://www.theguardian.com/world/live/2026/aug/04/europe-drought-extreme-heat-wildfires-climate-crisis-hungary-romania-ceuta-spain-migration-eu-latest-news-updates

This is just the latest in a deeply disturbing trend that casts Scottish Labour’s support for UK Labour’s nuclear energy strategy.

Electricité de France (EDF) shut down the Golfech-2 nuclear reactor in southern France amid a heat wave pushing temperatures toward 40°C in parts of Europe. This is the latest in a record number of heat-related outages for France’s nuclear fleet this summer, reducing output from a key part of Europe’s electricity system. EDF also warned that the Tricastin plant could face production cuts overnight due to high river temperatures limiting cooling.

Many French nuclear plants use river water for cooling and discharge warmer water back into the rivers. Environmental rules restrict these discharges when river temperatures are already elevated, forcing reactors to cut output or shut down. A power trader noted that the heat wave is a major factor affecting French nuclear power, with concern over how long it will last and whether it will worsen. French evening power prices in July have been higher than in any other year on record except the 2022 energy crisis. They were expected to reach about €200 per megawatt-hour that evening (up from around €5 near noon). https://financialpost.com/pmn/business-pmn/france-shuts-off-more-nuclear-power-as-heat-builds-across-europe

Elsewhere in Europe, Hungary’s Paks nuclear plant planned to cut capacity at block 2 by 50% due to low Danube water levels (the fourth such cut in two days). https://www.bloomberg.com/news/articles/2026-07-30/france-shuts-off-more-nuclear-power-as-heat-builds-across-europe

That’s not all:

United States examples going back 14 years:

• Millstone (Connecticut, 2012): Unit 2 was shut down because Long Island Sound water exceeded the 75°F (≈24°C) intake temperature limit for cooling. https://grist.org/climate-energy/hot-seawater-forces-shutdown-of-nuclear-reactor-in-connecticut/
• Browns Ferry (Alabama, TVA): Multiple reductions (e.g., 2010, 2011, and other summers) when Tennessee River temperatures rose too high, sometimes cutting output by ~50%. https://electricityforum.com/news/tvanuclearplantsoverheatingtenesseeriver
• Illinois plants (2012 heatwave): Facilities such as Braidwood, Dresden, LaSalle, and Quad Cities sought temporary variances to discharge-temperature limits or reduced output due to hot cooling water/ponds. https://openei.org/wiki/Powerplant_Curtailments

Roughly 45% of U.S. nuclear capacity uses once-through (open-loop) cooling that is more vulnerable to high water temperatures. https://www.industrialinfo.com/iirenergy/industry-news/article/rising-temperatures-could-cause-more-unplanned-outages-at-nuclear-plants–360468