A co-simulation workflow to evaluate the building level performance of Vertical Greenery Wall Systems in climate change scenario for office buildings in temperate climate

The impacts of climate change, excessive greenhouse gas emissions, and the current energy crisis have motivated the European Union to adopt mitigation and adaptation strategies. In the deep renovation of buildings, whether public or private, the adoption of resilient technologies is considered crucial to achieve significant improvements in energy efficiency and environmental sustainability. Among these, non-traditional solutions are gaining ground, such as Vertical Greenery Systems (VGSs), these include green façades, characterised by a vegetative layer self-developing on the vertical surface or on a support media, and living walls, integrating vegetation into the façade construction with plants and substrate placed on the vertical surface of the exterior wall.

Provided the lack of thermo-physical details and integration of existing VGS models in literature, In previous work the authors developed two Python-based mathematical models describing the hygrothermal behaviour of VGS (both green facades and living walls), based on literature.

The present present aims at evaluating the potential building performance of VGS systems in terms of impact on thermal delivered energy use (heating and cooling), overheating discomfort and thermal resilience indicators, in the context of climate change, and compared to more traditional opaque building envelope solutions (i.e. ETICS system). This is achieved by developing a co-simulation framework based on EnergyPlus and integrated in parametric SW (Grasshopper for Rhino), to integrate VGS models with building scale dynamic energy model simulation, applied on the case of the deep refurbishment of an archetypical existing building in the context of northern Italian climate (one of areas in EU affected by climate change in terms of heat waves and average temperature rise).

The results show that adopting green solutions for the building envelope can contribute to achieving building energy efficiency and thermal resiliency goals in a climate change scenario, and that the modelling of these technologies can be easily integrated into building level models for dynamic energy simulation.