Passive resilience solutions and their impact on a cold climate building during a power outage

This study investigated the impact of prolonged power outage during cold winter conditions on the thermal resilience of Finnish residential buildings. Detached houses and apartment buildings representing different energy efficiency levels were dynamically simulated using EnergyPlus for locations in southern (Helsinki -Vantaa) and northern (Sodankylä) Finland. The analysis assessed indoor temperature evolution, hours of safety under cold stress conditions, and recovery performance through energy demand and recovery duration. Structural thermal performance improvements through renewal or refurbishment of building structures up to current standards were evaluated as passive solutions to improve both passive survivability and energy efficiency. Results indicate the effectiveness of higher energy efficiency class and improvements in increasing passive survivability in residential buildings. All studied detached houses were vulnerable to winter power outage with the low safe hours inside indicating the need for external backup power or thermal energy supply. Recovery from the power outage was dependent on initial and developing indoor and outdoor conditions and the capacity of the original heating system. The findings highlight the interdependence between energy efficiency and thermal resilience and can provide useful insights on critical infrastructure planning by estimating service demand during prolonged power disruptions. Future work should consider buildings with varying thermal masses, a broader set of solutions, including local generation and storage, and more human-centric performance indicators to extend these results to wider resilience planning.