Risk assessment and resilience enhancement strategies for urban power supply-demand imbalance affected by extreme weather: A case study of Beijing

Abstract

Extreme weather and climate events (EWCE) risk assessment and system resilience enhancement are important supports for urban power systems to cope with global climate change and realize green and low-carbon transformation. However, the existing risk assessment methods tend to ignore the impact of cumulative damage events, and lack the systematic analysis of the power supply process. Moreover, there is a deficiency in researches on resilience enhancement strategies with application analysis in practical scenarios. This study established a risk assessment methodology with the occurrence probability of extreme weather, the deviation state of power supply-demand and the state duration as the first-level indexes. The methodology was applied to the assessment of three EWCE scenarios using the urban power structure of Beijing as a case study. Finally, the power supply resilience of EWCE was defined, and the power supply resilience curves with severe impacts and cumulative damages were characterized, and then resilience enhancement strategies were proposed to guide the case applications. The results of the study suggest that coupled extreme weather scenarios and an increase in the percentage of electricity supplied from renewable sources would increase the level of supply imbalance risk. System resilience could be improved by extending the time for supply level minimums to occur and by increasing the level of supply capacity minimums. Beijing would need to focus on the resilience enhancement for extreme low temperature and heavy rainfall superimposed on heat wave. This study could provide theoretical reference for the construction of resilient cities under climate change.