Energy Saving Assessment of Semi-Transparent Photovoltaic Modules Integrated into NZEB

Photovoltaic semi-transparent materials (STPV) integrated into glazing systems can offer good potential for energy saving to buildings, influencing heating loads, cooling loads, and lighting, as well as electricity production. Moreover, with the new stringent regulations issued by various European countries, following the Energy Performance of Buildings Directive (EPBD, 2010/31/EC), the building envelope, including the glazing elements, needs to have high thermal performance to guarantee Nearly Zero Energy Building (NZEB) behavior. This work presents an assessment of energy saving potential of 4 different types of STPV with respect to conventional double pane glass. Dye sensitized solar modules (DSM) and thin film modules were considered in the study. Simulations based on an IEA reference office building (STD) and on reference buildings prescribed by the new Italian building energy performance regulation (NZEB) were carried out. All the glazing peculiarities could be simulated using only one simulation tool, namely IDA ICE 4.7.1. Dye sensitized solar modules resulted as the best performing devices for all orientations and climate zones. The work also evidenced how the requirements of NZEB seem to be too stringent for insulation properties, especially for the climate zone of Rome.