How Climate Ambition and Technology Choices Shape Water Use in the Power Generation Sector

The power generation sector is a major contributor to global greenhouse gas (GHG) emissions and a significant consumer of freshwater, due to the extensive water use in cooling processes of thermoelectric power plants. While net-zero strategies increasingly focus on eliminating emissions to mitigate climate change, the critical role of water as a key sustainability resource remains underexplored and often underrepresented in mitigation scenarios, strategies, and policy frameworks. This study examines the impact of power sector decarbonization on global and regional electricity-related water demand under two climate ambition scenarios: continuation of current climate policies (CP) and a net-zero emission (NZ) scenario where countries implement their net-zero pledges by 2050 or later. Using the PROMETHEUS energy system model, we quantify how different climate ambitions could affect global and regional water demand, considering different levels of cooling technology evolution. Results show that water demand is not only driven by how much energy is produced but by the technology mix used to generate electricity. The findings highlight the significant co-benefits of power sector decarbonization for reducing water needs and ensuring freshwater resource sustainability, underscoring the importance of integrating water management into climate policy frameworks. This integrated perspective is critical for policymakers, energy system planners, and water resource managers aiming to balance ambitious climate goals with sustainable water use amid growing climate and resource challenges.