Photovoltaic BIPV Systems and Architectural Heritage: New Balance between Conservation and Transformation. An Assessment Method for Heritage Values Compatibility and Energy Benefits of Interventions

Abstract

This paper proposes to identify an approach methodology for the incorporation of building-integrated photovoltaic systems (BIPV) in existing architectural heritage, considering regulatory, conservation and energy aspects. The main objective is to provide information about guidance criteria related to the integration of BIPV in historical buildings and about intervention methods. That will be followed by the development of useful data to reorient and update the guidelines and guidance documents, both for the design approach and for the evaluation of potential future interventions. The research methodology includes a categorization and analysis of European and Swiss case studies, taking into account the state of preservation of the building before the intervention, the data of the applied photovoltaic technology and the aesthetic and energy contribution of the intervention. The result, in the form of graphic schedules, provides complete information for a real evaluation of the analyzed case studies and of the BIPV technological system used in historical contexts. This research promotes a conscious BIPV as a real opportunity to use technology and a contemporary architectural language capable of dialoguing with pre-existing buildings to significantly improve energy efficiency and determine a new value system for the historical building and its environment.

A review of Building integration of Solar PV Systems

“…Utilizing colored PV in a creative fashion has the potential to increase social acceptance of incorporating building-integrated photovoltaics (BIPV) into existing historic buildings. [39].…”

The Challenge of Rehabilitating Relocated Listed Heritage Buildings: Requirements and Opportunities

“…Now, it is increasingly possible due to the high compatibility of new products. The integration of photovoltaics (PV) in historic buildings will challenge both the preservation of heritage and the need to adapt to provisions concerning energy improvement by using renewable energy [76].…”

“…Considering aesthetics and function, building integrated photovoltaics (BIPV) can satisfy strict requirements governing heritage conservation, whereas standard building applied photovoltaics (BAPV) would be prohibited [69]. Not only do BIPV systems contribute to generate electricity, but they are also a constructive part of the building envelope [11,76]. Using BIPV as cladding or roofing could lead to less material usage and potentially reduced costs compared to BAPV [16].…”

“…Using BIPV as cladding or roofing could lead to less material usage and potentially reduced costs compared to BAPV [16]. New product designs allow better integration of BIPV in historic buildings due to similarities towards traditional building elements [76], for instance: "crystalline silicon modules, thin films, coloured solar cells, homogenised black appearance and integration of high-resolution images" [72]. Future developments and opportunities with new BIPV systems are explored by Jelle et al [11] and Jelle [15].…”

“…The market is receptive to new solar products that will satisfy regulations and requirements [35]. Polo López et al [76] emphasize that coloured PV recently has been considered a necessity for gaining market acceptance, as they allow better integration in historic buildings and landscapes. The colour in BIPV or BAPV appears from "coloured glass, pattern coatings or printing on front glazing treatments or coverings".…”