Abstract
This paper reviews the main energy-related features of building-integrated photovoltaic (BIPV) modules and systems, to serve as a reference for researchers, architects, BIPV manufacturers, and BIPV designers. The energy-related behavior of BIPV modules includes thermal, solar, optical and electrical aspects. Suitable standardization to evaluate heat transfer and solar heat gain by BIPV modules still need to be developed further since BIPV elements behave differently to the building elements they substitute. The optical properties of BIPV modules, such as light transmittance or color rendering, also play a role in the search for a good balance between energy saving, electricity generation, aesthetics and visual comfort. However, architecturally adapted BIPV design may affect the electrical performance also, by reducing the efficiency of BIPV modules and systems compared to standard photovoltaic (PV) ones. This is not the sole challenge for the electrical designers, as the special operating conditions of BIPV systems such as non-homogeneous irradiance complicate the electrical design and the forecasting of BIPV performance. The aim of this review is to present the current state of knowledge of the aspects mentioned above, to promote continued progress in BIPV and to inform suitable standardization efforts.