Thermal analysis of a new modular system for green walls

Abstract

Green walls can protect building envelope from surrounding environment while contributing to improve buildings design and thermal performance. The design concept of a new modular system (Geogreen) for vegetated surfaces has been developed to create more sustainable green roofs and green walls.This paper aims to present the study of Geogreen system thermal performance in a Mediterranean climate. This work is based on the evaluation of local meteorological conditions in three different periods. The Geogreen system is tested in an exterior test cell, comprising a reference wall and a wall covered with Geogreen modules. The analysis is based in the interior surface temperatures and interior surface heat fluxes of two compartments with the same dimensions and thermal characteristics.Resuts show that Geogreen system contributes to: reduce maximum interior surface temperatures and increase minimum interior surface temperatures up to 7°C; mitigate heat transfer, reducing maximum income heat flux by 75% and maximum outgoing heat flux by 60%; enhance thermal insulation of a wall; and increase thermal delay between the exterior and the interior. These aspects can lead to reduce and shift air-conditioning power loads and to improve buildings thermal performance.