Water footprint of thermal power in China: Implications from the high amount of industrial water use by plant infrastructure of coal-fired generation system

摘要

To reflect an important aspect of the water footprint of thermal power in China, this study as an extension of a previous work (Wu et al., 2018a) uncovers the high amount of industrial water use induced by plant infrastructure of a typical coal-fired power generation system. The systems process method is used by combining process analysis and water intensities obtained from systems input-output analysis. Industrial water use induced by plant infrastructure is accounted to be several times greater than previous estimates, and approximate to or much larger than that induced by fuel mining, preparation and transport in total. For per unit of electricity output, the water use by plant infrastructure amounts to 8.4% of the direct freshwater withdrawal for the majority of supercritical thermal power plants equipped with wet tower cooling, and even up to 38% of the freshwater withdrawal for some plants with air tower cooling. The annual water use induced by coal-fired power generation infrastructure in China is estimated to be 0.6%, 7%, and 23% of the annual freshwater withdrawal by China, Japan, and United Kingdom, respectively. The outcome provides a benchmark for policy makers to measure and curb the upstream water use by plant infrastructure.