How internal heat loads of buildings affect the effectiveness of vertical greenery systems? An experimental study

• Published in: Renewable energy 2020-05, Vol.151, p.919-930
• Main Authors: Coma, Julià, Chàfer, Marta, Pérez, Gabriel, Cabeza, Luisa F.
• Format: Article
• Language: English
• Subjects: Arquitectura; Buildings; Edificis; Energy conservation; Estalvi d'energia; Internal heat loads; Jardins verticals; Occupancy; Passive energy savings; Vertical gardening; Vertical greenery systems; Àrees temàtiques de la UPC
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2019.11.077

Nature-based solutions applied to the building skin, such as green roofs and vertical greenery systems, are standing out as the most promising by contributing with thermal improvements at building scale. From previous research done by GREiA research group at the University of Lleida (Spain), energy savings up to 58% were obtained by implementing vertical greenery systems on external building walls for cooling purposes. However, since there exist other passive and active energy saving technologies in the literature review that were limited their cooling and heating capacity after implementing internal heat loads, new experimental tests for two different vertical greenery systems simulating the heat loads in both, summer and winter were conducted in this research. Additionally, these experiments also improve the scarce and controversial literature for winter conditions. The results demonstrated that considering internal loads in experimental investigations is crucial for the results of the effectiveness of the green walls and green facades. The energy savings of VGS were reduced between 22.5% and 26.7% because of the internal loads for cooling purposes, and increased about 3.6% and 3.1% for heating. •Seasonal energy analysis of two vertical greenery systems implemented in buildings.•Experimental study of VGS considering internal heat loads generated by occupancy.•The thermal performance of VGS decreased due to internal heat loads.•During cooling periods there is still large energy saving potential by VGS.•VGS provide high thermal stability in summer but also in winter periods.