The use of vertical greening systems to reduce the energy demand for air conditioning. Field monitoring in Mediterranean climate

Green envelopes can provide environmental and ecological benefits in dense urban areas, improving air quality, mitigating Urban Heat Island effect, reducing energy use for air conditioning. The aim of the research presented is to determine the performance of vertical greening systems in the Mediterranean climate of Italy, analyzing a pilot project built in the city of Genoa. The authors performed an experimental investigation to evaluate the cooling potential of a well vegetated vertical greening system during summer. Field monitoring of the pilot project INPS (National Institute of Social Insurance) Green Façade, installed in 2014 on the south wall of an office building built early in the last century and renovated in the 1980's, demonstrates that a green layer can mitigate outdoor and surface temperatures, thus improve conform conditions and reduce building surfaces warming up (contributing to urban heat island mitigation). The cooling capacity of vertical greening systems can be exploited to reduce energy demand for air conditioning (with a theoretical energy saving potential of 26% for summer season). Although the energy saving for cooling strongly depends on several factors, the results obtained show a potential significant reduction of energy need for air conditioning.