Colored BIPV glass modules: the “price” of aesthetics

The use of renewable energy systems represents a crucial factor for realizing energy efficient constructions and achieving a significant energy and emissions savings in buildings. Photovoltaics (PV) is recognized as one of the most reliable solutions to be used in future buildings for producing electricity and transforming the building skin from a passive barrier towards a sensible, active and adaptive interface. In detail, Building Integrated Photovoltaic (BIPV) glass modules, used for transparent facades, skylights or balustrades, are a promising way to integrate solar energy into building envelope since they can contribute both in a passive and active way within the bioclimatic design. However, so far BIPV glass modules are still considered as a solution for exclusive constructions, due to design and installation complexity, additional requirements, higher costs in comparison to conventional photovoltaic modules and the “new” architectural language of the building skin. Within this framework Smart-Flex is an European project that aims to overcome some of the barriers by means of the demonstration of the flexible manufacturing of multifunctional BIPV glass elements at the industrial scale and their use for “conventional” buildings. Indeed, an intelligent and automatic manufacturing process has been developed, as well as a novel digital printing for glass. Thanks to such innovations, it is possible to customize the BIPV glass modules with the desired geometry, patterns and colors to replace perfectly the conventional building envelope components. However, the partial covering of the BIPV glass modules due to the printing, on one hand, contributes to design the aesthetical appearance of the facade but, on the other hand, it involves a “price to pay” in the final power output. Therefore, this paper focuses on experimental activities done by the authors to evaluate the electrical behavior of different colored modules developed in the framework of the Smart-Flex project with the goal to point out novel approaches for the customization and design of “active” coloured facades.