Assessment methodology for the resilience of energy systems in positive energy buildings

• Unfavorable weather increases power outages, impacting energy system resilience. • Battery capacity alone is insufficient to mitigate unfavorable weather effects. • Novel evaluation method with three resilience indicators reveals system weaknesses. • Weather conditions from the previous day are critical for resilience planning. Distributed renewable energy systems are emerging in communities and buildings in response to global warming. Concurrently, the frequency of large-scale power outages, which are often triggered by natural disasters and heavy rainfall, has increased. This trend highlights the necessity to develop robust energy systems that integrate distributed renewable energy with other sources. Economic and resilience assessments of photovoltaic (PV) and battery systems within infrastructure contexts have been extensively studied. However, resilience evaluation at the building level is necessary. Given that energy resilience encompasses various assessment aspects, the importance of employing multiple indicators for a comprehensive quantitative evaluation of resilience in PV and battery installations is increasing. This study introduced a methodology to quantitatively assess the resilience of energy systems. It employs multiple resilience indicators and simulates a power outage scenario in a positive energy building (PEB) equipped with PV and batteries. Additionally, this study analyzed the impact of different weather conditions on resilience. An assessment using multiple resilience indicators reveals that energy systems are more resilient on favorable weather days and that resilience is maximized when supply interruptions coincide with daylight hours. Furthermore, while no single indicator can measure resilience, this study shows that the use of multiple indicators enables the clarification and comparison of electricity supply and demand conditions during a disaster.