Unraveling energy-water nexus paths in urban agglomeration: A case study of Beijing-Tianjin-Hebei

Energy and water are closely intertwined within economic sectors in urban systems. The direct and indirect linkages between them in economic systems, termed the energy-water nexus, have been widely studied from production and consumption perspectives. However, the step-by-step linkages from initial production to final consumption remain unclear, particularly the indirect linkages. In this paper, we develop a multiregional energy-water nexus path model based on multiregional input-output analysis and structural path analysis. The results show that the top 50 ranking paths of water-related energy induced by rural household, urban household, and government consumption account for 84%, 82%, and 90%, respectively, of total flows, whereas the corresponding figures for energy-related water are 57%, 58% and 76%, respectively. The proportion of the top 50 paths within total paths is much lower for energy-related water than is the case for water-related energy. Sectoral flows within Beijing-Tianjin-Hebei account for 87% of the total, whereas cross-regional flows only account for 13%. By comparing the energy-water nexus from production, consumption, and supply chain perspectives, we aim to identify the critical, yet often overlooked, energy-water nexus paths and transmission sectors to enhance coordinated energy-water management in urban systems.