Thermoelectric generation requires large amounts of water for cooling. Recent warm periods have led to curtailments in generation, highlighting concerns about security of supply. Here we assess EU-wide climate impacts for 1,326 individual thermoelectric plants and 818 water basins in 2020 and 2030. We show that, despite policy goals and a decrease in electricityrelated water withdrawal, the number of regions experiencing some reduction in power availability due to water stress rises from 47 basins to 54 basins between 2014 and 2030, with further plants planned for construction in stressed basins. We examine the reasons for these pressures by including water demand for other uses. The majority of vulnerable basins lie in the Mediterranean region, with further basins in France, Germany and Poland. We investigate four adaptations, finding that increased future seawater cooling eases some pressures. This highlights the need for an integrated, basin-level approach in energy and water policy.T he electricity sector comprises at least 20% of total water withdrawal in most EU nations and approximately 55% on average across the EU 1 . The predominant use is for cooling within thermal power plants and takes place within a few hundred metres of the power plant itself 2 . Water withdrawal places local pressures on the social and ecological environment and is set to develop further under climate change as precipitation patterns change and average ambient temperatures increase [3][4][5] . In recent years, severe water shortages have occurred throughout the EU, for example during the summer droughts of 2003 and 2006, resulting in power curtailments 2 . As periods of water shortages in the EU are projected to increase due to climatic changes, understanding these impacts on the energy system becomes an essential component of EU climate change adaptation and mitigation analysis 6 . The EU has positioned itself as an international leader in the development of climate-energy policy 7 . EU targets for renewable energy, which withdraws negligible water, would be assumed to reduce thermoelectric water stress across the EU into the future 8 . Water use in power production has drawn increasing interest as researchers and policymakers have become aware of the growing sensitivity of the energy system to water availability 9,10 . Research has focused on water footprint analyses, where different approaches have been used to determine the water requirements of energy and fuel production both at the individual plant 2 , and regional level 11 . As the footprint of stationary electricity generation is almost entirely attributed to cooling requirements rather than fuel extraction or refinement 2 , studies have focused on the water footprint of electricity production (WFEP) from the power plants themselves [11][12][13][14] . Connecting these footprints to water availability and temperature is an important next step to providing insight into sensitivities of the electricity system to water resources. Fricko et al.11 considered the impact of energy...