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• PCM passive system was coupled with natural ventilation. • PCM melting temperature was optimized in different climate zones. • Airflow rates were numerically calculated based on the wind and buoyancy effects. • Two control strategies were implemented to maximize the utilization of ventilation. In recent years, the building sector has been responsible for continuous increase in energy consumption in the world. Space heating and cooling accounts for 34% of this energy consumption in buildings. In this context, using thermal energy storage (TES) can reduce energy consumption for space air conditioning. The use of phase change materials (PCM) as latent heat thermal energy storage (LHTES) system in the building envelope has been of great interest for passive cooling applications due to the high energy storage capacity of this technology. However, in order to utilize the full potential of a PCM, it needs to be fully charged at each cycle. Ventilation during the night is an effective method which can be used in PCM-enhanced office buildings with the aim of charging the PCM every required cycle. In the present study, PCM melting temperature of office building in various climate conditions was optimized using a simulation-based optimization and coupled with free cooling operation. Ventilation control strategies were used to improve the cooling energy performance of the PCM enhanced building integrated into envelopes. It was found that charging PCM with night ventilation, especially when using some specific control strategies of natural ventilation operated by external windows opening results in considerable cooling energy savings. The study was conducted for 15 different cities around the world. It was found that, in hot arid conditions, PCM passive cooling system was ineffective. Although, the energy savings were improved by coupling PCM and natural ventilation in these climate conditions. But the benefits were more or less similar to using natural ventilation only. On the other hand, in temperate condition, the effectiveness of PCM was increased from 3.32% to 25.62% by coupling a PCM passive system with night ventilation. It was further improved to 40% when using PCM with temperature-controlled ventilation. Moreover, it can be said that smart control of ventilation can lead to considerable energy savings. [ABSTRACT FROM AUTHOR]

• TABULA home archetypes are white-box modelled with realistic occupant variables. • Model parameters narrow the gap between calculated and measured energy use to 5–10%. • In temperate climates, measured heat energy is 22–32% below steady-state simulation. • Deep retrofit of an old home with modern boiler achieves up to 60% energy savings. • Shallow retrofit of a modern home achieves climate action target with heat pump only. Recent climate action plans set ambitious targets for large-scale home energy retrofit. These retrofit targets also recommend switching from oil boilers to electrical heat pumps. One area-based approach to retrofit is neighbourhood scale. Ideally with local community participation, neighbourhood retrofit improves a group of structurally similar homes, of the same archetype. Defined home archetypes already exist for 20 European countries thanks to previous research. That same research attempted steady-state calculations of space heating energy using the ISO 13790 Seasonal Method. Those calculations diverged from measured energy use by a large gap. Taking example home archetypes from Ireland, this study narrowed this energy-use gap by incorporating realistic parameters and schedules. Physical white-box models were constructed in DesignBuilder, and simulated by EnergyPlus with local weather data. The simulations combined realistic heating schedules, internal gains, infiltration and ventilation; converging simulation energy use with typical measurements and mostly achieved model calibration indices. Therefore, the resultant energy-use data was capable of tuning future grey-box models to investigate home energy use across ranges of heating patterns and heating setpoints. The aims of this study are threefold. First, devise a repeatable method to produce heat energy-use values by simulating white-box models of home archetypes, that enable tuning of future grey-box models. Second, specify the heating variables that result in acceptable energy-use gaps between simulation of home archetype models and their typical measurements. Third, test if the retrofits of three Irish home archetypes under a typical occupant schedule, achieve national climate action targets. [ABSTRACT FROM AUTHOR]