Living wall system for improved thermal performance of facades located in tropical climate. Case study in Dominican Republic

Abstract

The tropical climate of the Dominican Republic generates a high energy demand for cooling buildings. In this respect, façade improvements as passive techniques can significantly reduce cooling energy needs and green walls are considered to be one of the most appropriate sustainable solutions. In addition, it is important to characterize the real behavior of Living Wall Systems (LWS) to know the effectiveness in terms of energy reduction. Therefore, the present paper aims to evaluate the thermal performance of a LWS with outdoor test cells located in a tropical climate. This work was focused on the evaluation of two different facades, a LWS and a reference façade in two scenarios, one using air conditioning and the other without air conditioning as a passive system. The samples are located in the city of Santo Domingo (Dominican Republic), which is a location characterized by a very high level of solar radiation, high temperatures, and wet and dry seasons. For the comparison, the parameters measured were air temperature, relative humidity, surface temperature, heat flux and energy consumption. In addition, a meteorological station was used to record environmental variables. Results demonstrate that the LWS in such climate conditions, helps to improve the internal thermal behavior of the buildings in comparison with the reference façade, presenting a maximum difference in air temperature between them of 7.43 °C in passive and 9 °C in active. In addition, LWS has a lower energy consumption with respect to the reference facade, thus contributing to energy savings in the Dominican Republic.