Recurring heatwaves and droughts will increasingly constrain output from Europe's inland, river-cooled nuclear fleet during summer peaks, heightening power-supply stress and adaptation costs in the most exposed countries and likely prompting greater investment in climate-resilient designs; however, this will not derail Europe's renewed interest in nuclear power. Romania fully shut down its sole nuclear plant on Aug. 13, taking the second and last reactor at Cernavoda offline after Danube River flows fell below record lows. The plant, which normally generates about 20% of the country's annual electricity output, had last stopped entirely due to a drought in 2003. This came after Hungary took all four reactors at Paks -- its only nuclear plant and source of about 40% of national generation -- offline on Aug. 2 for the first time in 44 years; rainfall has since slightly raised Danube water levels enough to restart two of the plant's eight turbines.