Solar potential analysis of building integrated photovoltaic panels as retrofitting solution for existing

According to the Global Status Report REN21, the building sector has a high impact on global energy consumption and greenhouse emissions. Starting from this consideration, several incentives and regulations have been produced by European Union members State to promote extensive retrofitting initiatives for existing facilities. Such efforts should be moreover read within the perspective of a European free-carbon economy within 2050 and the framework set by United Nations' Sustainable Development Goals (SDGs). Despite the growing interest in the topic, industrial buildings have been often neglected even if production activities and releated processes are higly energy intensive as well. This is also due to the insufficient thermal, energy and environmental performance of the facilities hosting manufacturers companies. Focusing on the Italian context and the Tuscany area specifically, the most of industrial facilities are old and no longer comply with current regulations. Moreover, a large- scale survey highlighted the absence of active systems for energy production from renewables, since no photovoltaic panels were retrieved on over 80% of 2000 industrial buildings. Given the need for both overall requalification for this building stock, the research aims at outlining possible architectural redevelopment solutions including PV panels integrated into rain-screen or ventilated facades to be installed as external recladding, enhancing at the same time thermal, energy and aesthetic standards. Referring to a representative case study facility in Tuscany, the energy production potential of a Building Integrated Photo Voltaic (BIPV) is evaluated by considering parameters such as the building's size and orientation. Considering central Italy conditions, PV panels on facades proved to be particularly suitable for wide and south-oriented wall surfaces to enhance energy production in winter periods (4.30 kWh/m2). On the other hand, N-S-oriented buildings are likely to produce more energy during summer enabling them to cover up to 94% of energy demand for cooling when coupled with heat pump generators. The results suggest a considerable solar potential to be unlocked by adopting PV cladding elements, allowing also to ensure significant yearly surplus energy production to be exploited for lighting, industrial processes or sharing in a renewable energy communities perspective.