Anagrafe della ricerca

The rising of ambient temperature consequent to global climate change has been identified as one of the main drivers of the building overheating, which determines higher energy demand and worsening of the indoor environmental quality. Overheating has also set new challenges for societies regarding risk and vulnerabilities for the human health. Besides the warming induced by long-term climate change, population in urban areas also experiences local warming with temperature higher than in the surrounding rural areas, due to the so called Urban Heat Island (UHI) effect. Though it has been widely acknowledged that the UHI has significant impact on building energy performance, only a limited number of studies succeeded to accurately quantify this variation, because of the challenges in acquiring climatic data at microscale and in modelling the drivers of UHI taking into account buildings and surroundings interactions. Compared to the Building Energy Modelling (BEM) used for single building simulation, the potentiality offered by the Urban Building Energy Modelling (UBEM) that applies to buildings at a larger scale, fails to effectively address the UHI, due to the scarcity of data with both finer spatial resolutions (i.e., climatic data at microscale) and larger spatial coverage of the outcomes (i.e., detailed mapping of urban areas). In addition, literature studies point out that investigating the UHI impacts on the building energy behaviour in the context of combined future climate change and urbanisation would be recommended in future researches. The CRiStAll project aims to overcome these research gaps by creating high spatial resolution climatic datasets, in which future weather files – generated assuming the IPCC (Intergovernmental Panel on Climate Change) scenarios – coupled with typical urban context configurations of Italian building archetypes, will be used to assess the UHI effects in short, mid and long-term. The analysis will be carried out for different Italian climatic zones and considering several urban context configurations at microscale, got by varying urban canyon parameters and assuming building archetypes of different use categories, construction periods, geometry and types of technical building systems. The urban configurations are then used to assess the climate resiliency of strategies that will include external surfaces treatment, passive and active building technologies. Numerical simulations will be performed using an UBEM tool implemented with typical urban configurations; the resulting Key Performance Indicators (KPIs) will concern both the building energy performance and the indoor/outdoor thermal comfort. The adoption of typical urban configurations would allow to increase the spatial coverage of the outcomes, thus providing public authorities with the possibility to map the UHI intensity for different urban areas, which would support informed decisions on energy policies for the forthcoming years.