Assessment of the Effects of the Cavity in BIPV Applications

Abstract

As building-integrated photovoltaics (BIPV) become a promising application of decentralized PV systems, it is important to accurately assess their behavior in buildings energy simulations. The module temperature is a major factor in assessing its lifetime and generated power. High module temperatures lead to significant performance deteriorations. The addition of cavity ventilation contributes to decreasing the cavity temperature and is expected to improve the overall performance of BIPV. Thus, the aim of this paper is to explore the impact of the dimensioning of the BIPV cavity and its inlets on the cavity temperature which directly affects the module’s operating temperature. The simulation model developed in previous work was then validated and expanded in order to add an adjustable opening to conduct a sensitivity analysis on the BIPV cavity inlet opening dimension. The projected model consisted of two main parts: a thermal model and an airflow model. These models interact to predict the impact of airflow through the cavity on the cavity’s temperature. The sensitivity analysis included a range of simulations while modifying the dimensions for the ventilation cavity geometry of the BIPV module. The results of the sensitivity analysis revealed that the cavity temperature decreased when the cavity opening was implemented. Different degrees of influence on the cavity temperature were observed by widening or tightening the opening to certain degrees.