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Interprovincial electricity transmissions have been utilised in China to overcome the country's imbalanced social-economic development and resource endowments. A bottom-up technology-based model is adopted to estimate water uses in electricity-exporting provinces to produce the transmitted electricity as well as opportunistic water savings in the receiving provinces. The results highlight that, in 2014, on a national scale, electricity transmissions generated co-benefit of saving 20.1 billion m³ of water nationally due to the electric power sector's water productivity differences in the exporting and importing provinces. Taking regional water stresses into account, 10.98 billion m³ of national scarce water saving is realized through electricity transmissions. Moreover, electricity transmissions by China's proposed 12 future transmission lines are expected to use additional 3.22 billion m³ of water in the electricity-exporting provinces. As more water-intensive technologies, e.g. open-loop cooling, are more commonly utilised in the electricity-receiving provinces, a total amount of 16.97 billion m³ of water use will be avoided nationally. Water-use efficiency for power production should be improved in all regions. Transmitted power imports should still be encouraged in water-scarce regions to alleviate their water stresses while power exports should be shifted away from water-stressed regions to water-abundant ones. Energy transformation by utilising gas-fired capacity and hydropower in water-abundant Southern China could be advanced. [ABSTRACT FROM AUTHOR]

Abstract China's household energy demands' life-cycle water uses from 2002 to 2015 are quantified with an Input-Output analysis disaggregating rural and urban impacts. 9.73 and 1.60 km3 of water was withdrawn and consumed respectively in the life cycle of Chinese household energy demands in 2015, which was dominated by power and heat uses. An average urbanite's household energy uses, including coal, gas, petroleum products, power and heat, require about four times of life-cycle water uses than its rural counterpart. Among all upstream sectors, while agricultural sectors accounted for the largest shares for all energy uses, oil and gas extraction made significant contributions to petroleum products and gas consumption. A Structural Decomposition Analysis is conducted to disentangle the impacts of four driving factors, i.e. population, demand, economic structure and technology. Population change reduced energy consumption's life-cycle water use for rural households but increased that for urban households. Each economic sector's water intensity decreases, which represent technology advancement, played the dominant role curbing household energy consumption's life-cycle water uses. While power and heat dominates the household energy use profile, urbanization is accompanied by household consumption shifting from coal to gas and petroleum products. In order to reduce household energy consumption's impacts and reliance on water resources, it is imperative to reduce energy production's water use by adopting water-saving technologies, such as air cooling, as well as to reduce upstream sectors' water intensities, such as by promoting drip irrigation. Highlights • Household energy demands' life cycle withdrew 9.73 km3 of water in 2015. • Urban households' energy demands use 4 time water than rural ones. • Agriculture contributed the most to final energy demands' upstream water uses. • Technology has offset the most water uses for household energy demands. [ABSTRACT FROM AUTHOR]

Abstract In China, vehicle electrification is developed as a way to decouple people's increasing demand for on-road transport and concerns for adverse environmental impacts. Replacing conventional fuel with electricity not only yields impacts on air pollution and greenhouse gas emissions, but also on water resources. This study addresses such impacts for the first time. Based on China's existing plans, we expect China's future electric vehicles will grow from 5 million in 2020 to 80 million in 2030, requiring 47 to 335 TWh of electricity supplies respectively. In order to produce such amount of electricity, under a baseline scenario, 42.60 million m³ and 1.09 billion m³ of water is projected to be consumed and withdrawn in 2020, respectively, which are expected to grow to 324.45 million and 8.56 billion m³ in 2030. Deploying renewable energies offers considerable potentials cutting electric vehicles' indirect impacts on water resources by more than 20% as their productions require less water inputs than coal-fired power plants. Changing cooling technologies' impacts differ by regions, increasing water consumption in southern regions while reducing water consumption in the north. However, if water consumption avoided from avoiding conventional fuel productions is taken into account, compared to the counterfactual scenario where the same number of traditional vehicles will be deployed, future electric vehicles in China will lead to net decreases of 19.3, 64.3 and 89.7 million m³ of scarce water consumption nationally under baseline, high renewable and cooling technology change scenarios in the electric power sector respectively. Highlights • Electric vehicle (EV) amount is expected to reach 80 million in China by 2030. • From 2020 to 2030, electricity demand by China's EVs will increase by 6 times to be 335 TWh. • 8.56 billion m³ of water will be withdrawn by electricity generation for EV in 2030. • EV rising can save water in North China by avoiding oil production. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Both water depletion and pollution by coal-fired power generation are quantified. • Petroleum pollutant determines the life cycle grey water footprint. • Water pollution mostly occurs in the fuel supply sector. • The grey water footprint was reduced by 49% from 2002 to 2012. Abstract In the present study, both water depletion and degradation in the life cycle of power generation at coal-fired power plants in China are quantified using a mixed-unit input-output model. National life cycle Withdrawal, Blue and Grey water footprint (WF) of thermal power production in China are estimated to be 35.46, 2.14 and 17.67 m3 per MWh of electricity produced, respectively. Those three types of life cycle WFs experienced significant reductions from 2002 to 2012 due to improved technologies such as water saving and wastewater treatment. Although Chemical Oxygen Demand (COD) pollutant had the largest discharge amount in the life cycle process of electricity generation, petroleum pollutant that was mostly discharged from coal production determined the Grey WF because of its lower permissible concentration. The spatial distribution of scarce WFs, incorporating regional water stresses, is also studied at the provincial level to identify the impacts of thermal power generation on regional water scarcities. Scarce water consumption was concentrated in northern China while scarce water was predominantly withdrawn in eastern China. [ABSTRACT FROM AUTHOR]

We quantify the current water use of China’s thermoelectric power sector with plant-level data. We also quantify the future implications for cooling water use of different energy supply scenarios at both a regional and national levels. Within China, water withdrawal and consumption are projected to exceed 280 and 15 billion m 3 respectively by 2050 if China does not implement any new policies, up from current levels of 65.2 and 4.64 billion m 3 . Improving energy efficiency or transforming the energy infrastructure to renewable, or low-carbon, sources provides the opportunity to reduce water use by over 50%. At a regional level, central and eastern China account for the majority of the power sector’s water withdrawals, but water consumption is projected to increase in many regions under most scenarios. In high-renewable and low-carbon scenarios, concentrated solar power and inland nuclear power, respectively, constitute the primary fresh water users. Changing cooling technology, from open-loop to closed-loop in the south and from closed-loop to air cooling in the north, curtails the power sector’s water withdrawal considerably while increasing water consumption, particularly in eastern and central China. The power sector’s water use is predicted to exceed the regional industrial water quota under the ‘3 Red Line’ policy in the east under all scenarios, unless cooling technology change is facilitated. The industrial water quota is also likely to be violated in the central and the northern regions under a baseline scenario. Moreover, in line with electricity production, the power sector’s water use peaks in the winter when water availability is lowest. Water-for-energy is a highly contextual issue – a better understanding of its spatio-temporal characteristics is therefore critical for development of policies for sustainable cooling water use in the power sector. [ABSTRACT FROM AUTHOR]