The energy-water nexus (EWN) is an important concept for advancing sustainability issues, especially in urban agglomerations with complex interactions between energy and materials. Based on the deficient analysis method of EWN assessment at urban agglomeration scales, we proposed an intercity method for compiling an urban agglomeration multiregional input-output table for exploring the nexus in urban agglomerations. After combining location quotients and a gravity model, a multiregional input-output table of an urban agglomeration was built based on provincial input-output tables. The detailed consumptions by water-related energy and energy-related water were then systematically calculated to investigate the EWN. A case study was conducted to demonstrate the scenario of coupled energy and water in 2015 for the Pearl River Delta urban agglomeration. The results showed that manufacturing plays an important role in both energy and water consumption, while agriculture consumed the largest amount of water, and transport consumed the largest hybrid energy in developed cities. Although with relatively high resource utilization efficiencies, the more developed cities in the urban agglomeration (e.g. Shenzhen, Guangzhou, and Foshan) still consumed large amounts of energy and water, implying the relatively great magnitude of resource consumption driven by the developed economies. On the whole, energy consumption increased from southwest to northeast, while the water consumption increased from southeast to northwest. It was found that Shenzhen depended mostly on other cities in the urban agglomeration for both energy and water, and that Huizhou was the most self-sufficient city. Based on the characteristics of the EWN in the Pearl River Delta urban agglomeration, it is suggested that local managers should improve vehicle fuel efficiencies, reduce water consumption rates for agriculture, save water for energy production, and optimize the structure of manufacturing. In addition to these findings, this work sets a baseline for EWN studies in urban agglomerations.

能源与水的关系（EWN）是推进可持续发展问题的重要概念，尤其是在能源和材料之间相互作用复杂的城市群中。基于城市群规模的EWN评估的不足分析方法，提出了一种城际方法来构建城市群多区域投入产出表，以探索城市群的联系。在结合位置商和引力模型后，基于省级投入产出表，建立了一个城市群的多区域投入产出表。然后系统地计算了与水有关的能源和与能源有关的水的详细消耗量，以研究EWN。案例研究表明，珠江三角洲城市群2015年能源和水的耦合情景。结果表明，在发达城市中，制造业在能源和水的消耗中都起着重要的作用，而农业消耗的水量最大，而运输消耗的能源量最大。尽管具有较高的资源利用效率，但城市群中较发达的城市（如深圳，广州和佛山）仍消耗大量能源和水，这意味着发达经济体带动了相对较大的资源消耗。总体而言，能源消耗从西南到东北增加，而水消耗从东南到西北增加。结果发现，深圳在城市群的能源和水上主要依赖于其他城市，而惠州是最自给自足的城市。根据珠江三角洲城市群的EWN的特征，建议地方管理人员应提高车辆的燃油效率，降低农业用水率，节约能源生产用水，并优化制造结构。除了这些发现之外，这项工作还为城市群的EWN研究奠定了基础。