Retrofit interventions with integrated PV-façades: Energy and economic scenarios for apartment buildings in Italy

This paper intends to propose an efficient and affordable solution for the energy retrofit of the European residential real estate built from the 1950s to the 1980s, with particular reference to multi-storey apartment blocks. To this aim, a typical apartment block located in a social housing district in Catania (Sicily) is considered. For this building, a versatile modular façade-system is adopted, hosting PV panels and current cladding materials. This system represents a good compromise in terms of texture, colour, weight and efficiency, while different panels may be combined for maximizing the solar energy collection and renovating the overall architectural image. The new cladding can be installed through a metallic frame, which would allow easy application and maintenance, as well as a rear ventilation of the panels. The effectiveness of the proposed solution in terms of energy balance is evaluated through dynamic simulations. In order to make general conclusions, a parametric analysis is also performed, by virtually changing the building orientation and the floor number, while also moving it to other climatic conditions. The outcomes allow to assess the energy and economic potentiality of integrated PV-façades, which may generate a significant impact on the retrofit of European multi-storey residential building stock.