Future nuclear power outages in a changing climate - A case study on two contrasted French power plants

Climate change is expected to cause significant differences in the quality and quantity of the water in rivers and lakes. These changes can become a critical issue for water-dependent energy assets, such as nuclear power plants. The goal of this study is to assess the impacts of climate change on the availability of two different French nuclear power plants located on riversides, the Meuse and the Garonne rivers. A modelling framework that was evaluated in a previous study was used to assess future plant outages in these case studies. This framework is based on bias-corrected projections for one emission scenario and 10 CMIP5 EURO-CORDEX climate models that feed a hydrological, water temperature, and cooling system modelling chain. The model projects a decrease in the flow rate of the Garonne River, and an increase in the mean temperature of the water in both rivers. As a result, the availability of both of these reactors is projected to decrease but remains under 2 % of the annual electricity production by 2050. • Decarbonizing the energy sector is urgent to tackle climate change mitigation. • Nuclear power plant regulation is strongly constrained by water quality and quantity. • An interdisciplinary modeling chain was used to project future nuclear power outages. • By 2050 decreasing annual streamflow and increasing water temperature are expected. • This will lead to a 2 % increase in future nuclear power outages.