Comparison of the Electrical and Thermal Performance of Double Skin Facade and Insulating Glazing Unit integrating Semi-Transparent Photovoltaics

The total cost for purchase and installation of photovoltaics has decreased by more than 60% for residential applications (5.7kWp) and more than 65% for commercial applications (larger than 200kWp) over the last 7 years. As the price of the photovoltaics decreases, the actual integration of PV into building envelopes has attracted the attention of the industry and consequently the scientific community. Building integrated Photovoltaics (BIPV) can replace building elements in both facades and roofs improving at the same time the thermal, the electrical and the daylighting performance of the building. Some novel approaches are the Double Skin Façade (DSF) and the Insulating Glazing Units (IGU) that integrate Semi- Transparent photovoltaics (STPV). The STPV in both cases is the exterior layer of the envelope, controlling in this way the solar gains but also allowing daylight into the interior space. For the case of the DSF, the air that passes behind the STPV can act as a buffer zone and depending on the preferred strategy, it can be used for heating, cooling or ventilating the building.