Heat collection in an attached sunspace

Abstract The attached sunspaces are classic bioclimatic systems. Normally, they are used as solar passive techniques in buildings. However, it has been suggested that they could also be used as active systems in order to collect solar energy and harness it in the heating, ventilation and air conditioning (HVAC) equipment. This paper analyses the sunspace built during the ARFRISOL project, which has a validated simulation tool of its thermal behaviour, developed in a previous research. In this paper, this tool is applied to study the possibility of the energy collection. Although this energy is not enough to be used as direct heating system, it can pre-heat the air before entering the HVAC equipment. Two configurations have been studied: collecting the energy during the whole day or only at night to take advantage of the sunspace thermal inertia. Also, the results obtained with these configurations have been compared with the sunspace used in passive mode. For this analysis, several characteristic days with summer and winter climatic conditions have been considered. Finally, an economic evaluation of this innovative system –a solar active sunspace- is performed taking into account the results of the different configurations.