Assessment of the water and energy nexus in the energy supply subsystem of water stressed countries like Iran

Iran, situated in the Middle East, is recognized as a prominent energy hub, with its economy heavily reliant on the exportation of energy. Iran currently faces significant water stress, underscoring the importance of examining its Water-Energy (WE) nexus. Hence, it is crucial to examine the Water-Energy (WE) nexus in this nation. This study evaluates Iran's WE nexus from upstream to downstream in its energy subsystem (2007-2017) through an integrated framework combining water footprint analysis, water consumption methodologies, and nexus system modeling. This study assessed the WE nexus from upstream to downstream in Iran from 2007 to 2017. Key findings reveal that steam turbine power plants, particularly Ramin and Neka, exhibit the highest water consumption intensities, approximately 2.04 and 2.65 m³/MWh respectively, making them critical targets for efficiency improvements or retirement. Conversely, combined-cycle plants with dry cooling technology show significantly lower water intensity (0.18 m³/MWh), presenting viable alternatives. The study recommends shifting energy infrastructure towards combined-cycle and gas turbine plants to mitigate water stress, thus providing actionable insights for sustainable energy and water resource management in water-stressed regions.