Italian Architectural Heritage and Photovoltaic Systems. Matching Style with Sustainability

Rehabilitation and management of pre-industrial architectural heritage over time has played a central role in the international scientific debate since the 1970s. In light of the experience gained in this field, the challenge of a controlled and consistent integration of Renewable Energy Sources (RES) requires a careful reflection on the compatibility criteria between new technologies and traditional building’s identity. Several of these technologies, such as photovoltaic (PV) systems, need to be placed on the building envelope or in appropriate outdoor areas, altering the architectural image and the landscape. Therefore, the characteristics of each building and its context should lead designers to choose solutions able to balance the need for increased energy production from RES with the need for preserving the identity of architectural heritage and landscape. A preliminary evaluation of rehabilitation projects allows to improve building sustainability and, in the meanwhile, to prevent any irreversible alteration of the cultural heritage. With reference to Italian case studies and guidelines for improving sustainability in energy production, the paper leads to identify evaluation criteria for the introduction of PV systems in pre-industrial buildings. Such criteria, which are based on architectural heritage values, allow for assessing the consistency of the building envelope alteration with conservation issues, in projects involving PV and, generally, solar technologies that need to be integrated with the building envelope.