Global assessment of clean water and energy provision strategies for adapting to droughts, heatwaves, and compound events

Climate change and increasing energy demand are placing severe pressure on clean water provision and water-dependent energy systems worldwide. Although climate impacts are widely studied, less attention has been given to how countries manage water and energy risks in conjunction. This study provides a global assessment of interacting water-energy risks by comparing reported management strategies to reduce “energy-for-water” and “water-for-energy” risks under climate extremes and evaluates water–energy interactions. Here we focus on energy-intensive water supply options (desalination, wastewater treatment/reuse) and water-dependent energy technologies (hydropower and thermoelectric power). A semi-structured literature review (2000–2025), supported by AI-assisted screening and information extraction, is complemented by an analysis of country-level indicators globally. Results show that adaptation strategies for clean water provision emphasise demand management and energy-intensive water supply technologies, particularly in countries with high water scarcity. However, the associated energy burden varies by technology choice: countries emphasising wastewater treatment and reuse (e.g., China and the United States) consume less energy than those relying primarily on desalination (e.g., Saudi Arabia and the United Arab Emirates). We also find that future-oriented discussions shift attention away from interbasin water transfers and storage expansion toward non-energy-intensive solutions such as institutional reform, economic water policy, and water demand management. Energy-sector adaptation strategies emphasise thermoelectric cooling-system shifts, reservoir optimisation, and energy mix diversification. Overall, our findings show that adaptation efforts remain fragmented across sectors, as adaptation planning typically lacks recognition of water-energy sector feedbacks. Opportunities for more coherent management include greater integration of water and energy infrastructure, for example through the use of treated wastewater for power-plant cooling, the recovery of waste heat for water treatment and desalination, and the strategic siting of water-intensive power generation facilities in areas with adequate water resources. Ultimately, effective adaptation under climate extremes requires a coupled water-energy infrastructure system whose resilience depends on coordinated technological, spatial, and institutional design.