# European drought slashes hydro and nuclear output

> Live situation record from CLSTR: https://clstr.news/situations/alpine-drought-impacts-hydroelectric-generation
> Updated: 2026-08-02T10:09:41.000Z. Sources: 11. Developments: 2.

The severe Alpine drought that drove Verbund’s July 2026 earnings gap continued to spread across Europe into early August. River levels remained far below normal, cutting run‑of‑river hydro generation to roughly half of typical output. In Austria, July output fell to about 51 % of the 15‑year average; Switzerland recorded 48 % of its average, while Germany’s EnBW hydro output was 63 % of its reference level in June and only about 80 % of the year‑to‑date target.

Nuclear plants were also forced to curtail or cease operations because of insufficient cooling water. Hungary’s Paks reactor stopped completely, Romania’s Cernavodă unit was disconnected, and six reactors across the EU—including facilities in France and the United Kingdom—were either fully shut or operated at limited output. Slovenia’s hydropower is projected to drop 39 % in July 2026 versus the same month in 2025.

The combined shortfall is being partially offset by increased photovoltaic generation and pumped‑storage capacity, and authorities say there is no immediate threat to supply security. Nevertheless, the energy deficit is expected to shave 0.1‑0.2 % off Germany’s third‑quarter GDP and raise transport costs for coal‑dependent industries.

## Claims

- EnBW's run‑of‑river hydro plants produced about 80 % of the reference output for the year to the end of June. (corroborated by 2 sources)
- EnBW's run‑of‑river hydro output fell to 63 % of the reference level in June. (corroborated by 2 sources)
- Iffezheim Rhine hydro plant produced about 83 % of its reference output year‑to‑date and 70 % in June. (corroborated by 2 sources)
- Neckar hydro plants produced about 83 % of possible output year‑to‑date and 61 % in June. (corroborated by 2 sources)
- Some smaller tributary hydro plants on rivers such as the Kocher, Enz, Jagst, Nagold and Untere Argen are offline or operating at reduced capacity due to low water levels. (corroborated by 2 sources)
- EnBW and its subsidiaries operate hydro facilities at 130 sites across Germany. (corroborated by 2 sources)
- Hungary's Paks nuclear plant stopped operating due to insufficient cooling water in 2026. (corroborated by 2 sources)
- Low water flow in the Danube in Austria has reduced electricity generation from run‑of‑river hydro plants below the seasonal average. (single source)
- Austria's energy ministry says the shortfall is compensated by photovoltaics and pumped‑storage plants, with no impact on supply security expected. (single source)
- Slovenia's hydropower generation in July 2026 is expected to be 39 % lower than July 2025. (single source)
- Low river levels could reduce Germany's third‑quarter GDP by 0.1‑0.2 %. (single source)
- Hungary's Paks nuclear plant stopped operating due to insufficient cooling water. (single source)

## Timeline

### 2026-08-02: European drought slashes hydro and nuclear power output

Europe's heatwave and drought have cut hydro output to 50‑80 % of normal and forced several nuclear reactors, including Hungary’s Paks, to shut down, threatening energy supply and modestly denting Germany’s Q3

8 sources. https://clstr.news/cluster/european-drought-slashes-hydropower-output-across-alpine-nations

### 2026-07-30: Austrian power producer Verbund posts record loss as drought slashes hydro output

Verbund’s hydro output fell due to a historic drought, creating a €370 million loss and cutting EBITDA by 25 % as the Austrian utility seeks diversification.

3 sources. https://clstr.news/cluster/austrian-power-producer-verbund-posts-record-loss-as-drought-slashes-hydro-output

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Cite as: European drought slashes hydro and nuclear output. CLSTR, https://clstr.news/situations/alpine-drought-impacts-hydroelectric-generation