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Along with electricity transmission, virtual water is transferred from electricity generation provinces to load hubs, reallocating spatial water resources and impacting regional water scarcity. To assess whether virtual water in electricity transmission mitigated or aggravated national water scarcity, a rationality assessment model was proposed from energy-water nexus perspective. The interprovincial virtual water flows were calculated based on provincial water intensity and electricity transmission considering the provincial electricity generation mix. The flow rationality index and node rationality index were proposed and defined to evaluate the net benefit of virtual water flows and provinces, respectively, according to the interprovincial differences in water stress index. The results show that: 1) a large amount of virtual water was transferred from the northwest and southwest provinces to the southeast provinces and Beijing-Tianjin-Hebei region; 2) the flow with the highest flow rationality index is Inner Mongolia-to-Hebei (29.8), while the lowest one is Shanxi-to-Hubei (−102.5); 3) the node with the highest node rationality index is Hebei (32.0), while the lowest one is Shanxi (−104.7). By quantifying the impacts of electricity transmission on provincial and national water stress, this study aims to provide guidance for national virtual water strategy by electricity transmission to mitigate national water scarcity. • Virtual water transfers embodied in China's interprovincial electricity trade is calculated in 2014. • A rationality assessment model is proposed to evaluate whether the water transfers positively or negatively impacts overall water scarcity for a region. • Based rationality assessment model, the rationality index for flows and provinces is analyzed. [ABSTRACT FROM AUTHOR]

Expansion of electric grid has induced increasing stress on regional water resources. Yet, few insights have been gained into the network dynamics of virtual water flows embodied in interprovincial electricity transmission. Here, we calculated the interprovincial transfer of virtual water and virtual scarce water associated with electricity transmissions in China during 2005–2014, considering both thermal power and renewable energies. To track the network dynamics of virtual water, we identified control and dependence relationships between provinces related to exchanging virtual water, using network control analysis. We found that the magnitudes of virtual water and virtual scarce water transferred from western provinces to the rest of China have increased five-fold between 2005 and 2014. The transfers of virtual water exacerbated the water scarcity in northwestern provinces over time, while the transfers between southwestern provinces mitigated the local water scarcity. Southwestern provinces have strong control over the Yangtze River Delta region due to the supply of virtual water in hydroelectricity transmission inbetween. In contrast, the interdependence among northwestern provinces has been strengthened over time. Gansu, Xinjiang and Inner Mongolia have become more dominant in controlling the virtual water appropriated by Beijing–Tianjin–Hebei region and Shandong over this period. We suggest that the dynamics of electricity-induced virtual water transfers across regions be regularly tracked to address water scarcity during constructing power plants and adjusting electricity dispatches. • Virtual water in electricity transmission has increased five-fold between 2005 and 2014. • Thermal power has a greater impact on virtual scarce water than virtual water. • Expansion of renewable energies in power system mitigated water scarcity in China. • The flow of virtual water has been controlled by more regions over time. [ABSTRACT FROM AUTHOR]