Spatialized carbon-energy-water footprint of emerging coal chemical industry in China

Concerns about energy security have driven the launch of the emerging coal chemical industry (ECCI) across China. However, the resulting spatially explicit carbon–energy–water footprint remains unclear. This study aims to comprehensively identify the spatial heterogeneity, distribution, and transfer characteristics of the carbon–energy–water footprint of the ECCI in China. An original spatialized accounting method based on a multi-flow multi-node model is developed to address the difficulty that spatially integrating large amounts of spatial data for ECCI projects and their upstream coal mines and power plants. The results indicate that the provincial intensities of the carbon footprint, energy footprint, and water footprint varied by −13.4–43.6 %, −7.2–1.8 %, and −22.6–59.5 % relative to the national averages, respectively. The three intensity types have quite different spatial heterogeneities, always showing an impossible trinity of carbon reduction, energy saving, and water conservation at the provincial level. The total national carbon footprint, energy footprint, and water footprint reached 280.20 Mt CO2-eq, 5.35 EJ, and 1155.18 Mt, respectively, of which more than 90 % were centrally distributed in North China, Northwest China, and East China. Interprovincial coal transport and electricity transmission driven by the spatial mismatch between the upstream and downstream processes together led to the transfer of 10.35 Mt CO2-eq of carbon footprint, 68.72 PJ of energy footprint, and 100.92 Mt of water footprint, whereas their respective contributions significantly varied by footprint type. These results provide spatial-specific knowledge and insights for layout optimization and sustainability enhancement for the ECCI across the country.