Neng Zhu

As the coupling and interaction among subsystems in integrated energy systems (IESs) increase, these systems are becoming increasingly vulnerable to failures under extreme weather events and natural disasters, which threatens overall operational security and stability. This paper reviews recent studies on the resilience-oriented management of IESs, with a focus on the characterization and assessment of energy system resilience covering various types of resilience-challenging extreme events, the related quantification metrics, methods, and resilience enhancement applications. Based on the reviewed studies, this paper attempts to figure out how internal and external adversities impact the systems, and identifies effective methods to detect, assess, and quantify system vulnerabilities and weak links under extreme events scenarios. Rather than confining the analysis to single-carrier systems, this study bridges cross-disciplinary perspectives to construct a resilience-oriented conceptual framework specifically designed for IESs, centering on the core logical, analytical, and technical strategies for both characterizing and advancing IESs’ resilience. Also, this review tries to reveal research opportunities to address significant gaps in the existing literature. Findings from the review can inform future research and help to develop scalable and effective ways to enhance IESs’ resilience.

Pipe-embedded walls offer a promising approach to reducing winter heating demand by mitigating envelope heat loss while maintaining indoor thermal comfort. However, most existing studies focus on single-pipe systems operating under high-flow conditions, with limited attention to low-flow operation and its implications for energy flexibility. This study investigates a parallel pipe-embedded wall system operating at low flow velocity as a flexible heating strategy. A three-dimensional CFD model was developed to analyze the coupled hydraulic and thermal behavior of the wall, including the effects of connecting columns, and was validated through experiments under identical boundary conditions. Parametric analyses examined the influence of main pipe size, branch spacing, flow velocity, water temperature, and column-induced thermal bridging. The results show that variations in flow velocity and branch spacing lead to flow distribution differences of up to 6%, while causing negligible changes in inner-surface temperature (below 0.1 °C). In contrast, increasing column size significantly intensifies thermal bridging, increasing inner-surface heat flux by approximately 21% as the column edge length increases from 200 mm to 400 mm. Overall, the results demonstrate that parallel pipe-embedded walls can enhance building energy flexibility by enabling stable thermal performance under low-flow operation.

Escalating global climate change and the intensification of urban heatwaves have led to an increase in summer air conditioning cooling energy consumption. This phenomenon is particularly critical in tropical regions, as it may trigger an energy crisis. The rational setting of indoor thermal design parameters can help conserve energy to the maximum extent while ensuring thermal comfort for occupants. This study selected Haikou City, a unique tropical city in China, as the research location. Indoor environment measurements and a questionnaire survey were conducted with participants, and the outdoor thermal environment sensitivity, population attributes and differences in thermal sensation, thermal neutral temperature, and comfort range were calculated and analyzed. The following results were obtained. Based on the overall population, long-term residence, and temporary residence classification, the indoor thermal comfort needs of residents in tropical cities in Haikou were effectively identified. The actual thermal neutral temperature of the overall population is 25.7 °C, and 90% of the acceptable thermal comfort temperature range is 23.2 °C–28.0 °C. The actual thermal neutral temperature of the regular residents is 27.3 °C, and 90% of the acceptable thermal comfort temperature range is 23.3 °C–31.4 °C. The actual thermal neutral temperature of the temporary population is 25.5 °C, and 90% of the acceptable thermal comfort temperature range is 23.0 °C–28.0 °C. These research results have an important reference value for improving the setting of the temperature of air conditioning in tropical areas in summer and further reducing energy consumption, which is conducive to sustainable development.