No abstract

The steadily growing market share of building‐integrated photovoltaics (BIPVs) places the aesthetics of solar modules in the focus of research and development. In this work, a colorization method based on inkjet‐printed reflective pigments is adapted for the emerging perovskite photovoltaics. Herein, not only excellent control of color impression, brightness, and pattern is demonstrated, but also angle invariant color perception, which makes the presented approach stand out among the many published colorization strategies for perovskite solar cells (PSCs). Compared to uncolored reference solar cells, bright magenta and yellow PSCs display a remarkable relative power conversion efficiency (PCE) of up to 65% and more than 11% absolute PCE. Moreover, PSCs with more BIPV‐relevant coloring patterns such as a mimic of a marble or corten steel surfaces are demonstrated. The colorization method presented is inexpensive and ready for scalable solar module production. To demonstrate the scalability of the proposed concept, a small‐area perovskite solar module (4 cm2 aperture area) in white marble optics exhibiting a PCE of almost 14% as a potential application is presented.

For the design of façade and roof glazing, loads due to dead weight, climatic loads (IGU - pressure differences), wind and snow are well investigated and are considered in engineering practice. However, glass constructions are also ex-posed to thermally induced stresses due to direct solar irradiation. The standards and guidelines available so far, both nationally and at the European level, are partly outdated or contain only simplified instructions and specifications for calculating thermally induced stresses of façade and roof glazing. Within the research project, a variety of façade glazing configurations and additionally building-integrated (BIPV) glass-glass photovoltaic modules, for example as a façade cladding rear ventilated, are being investigated by means of numerical simulation and subsequent experimental validation with up-to-date German meteorological data. The purpose of the project is to reduce or prevent the occurrence of thermally induced glass breakage (thermal breakage) through European standardization. In this way, economic damage can be avoided. The present paper provides an insight into the two-years lasting joint research project, including the current status of science and technology, goals, structure and process, and descriptions of work packages. Results, such as the collection of the various influencing factors, meteorological data, and results from numerical simulations, will be presented after the project has finished at the end of September 2022.

Die Fassade des 2012 fertiggestellten Bürogebäudes Z3 in Stuttgart ist Gegenstand intensiver Forschung. Derzeit werden die vorgehängten, hinterlüfteten Einscheiben‐Sicherheitsgläser (ESG) über lastabtragende Klebungen auf der Unterkonstruktion gehalten. Im Rahmen eines EU‐Projektes wird eine neue Verbundverglasung mit integrierter Photovoltaik entwickelt, die die bestehende ESG‐Verglasung auf der Südseite des Gebäudes ersetzen soll. Der rückseitige Lastabtrag wird ausschließlich über strukturelle Klebungen ohne mechanische Sicherung erfolgen. Eine besondere Herausforderung dieser Konstruktion besteht im dauerhaften Lastabtrag der einzelnen Komponenten und dem Erfüllen der Anforderungen für eine Zustimmung im Einzelfall (ZiE). Der vorliegende Beitrag zeigt und bewertet eine Auswahl konstruktiver Lösungsansätze. New Z3 façade in Stuttgart – Load bearing bonded Photovoltaics. The façade of the Z3 office building Z3 in Stuttgart, completed in 2012, is subject of intensive research activities. The existing ventilated glass cladding is made of toughened safety glass panes, which are adhesively bonded to the substructure. A new laminated glass build‐up with integrated photovoltaics is under development within the framework of an EU project. The new glass built‐up replaces the existing single glass panels on the south façade of the building. The loads are transferred exclusively via structural bonding at the back side of the façade panels without any mechanical fasteners. A particular challenge is the durable support of loads and fulfilling the building authorities’ requirements. This paper presents and evaluates a range of constructive solutions.

BIPV modules provide a high degree of design possibilities and additional functionalities in combination with the plain electricity generation well known for standard photovoltaic installations. Consequently, the specialized know-how to understand BIPV, properly design and manufacture them requires much more than the electrical knowledge developed and applied in standard photovoltaic systems. Expertise of building physics and building regulations are also required on a high level. As BIPV modules are usually custom designed, typical electrical design and simulation tools cannot be used without modifications, while deeper insight of complex shading influences and specialized overall system design are advantageous. Authors of this publication were involved in well over 1000 BIPV system designs and developments, and their experiences are shared. Recurring questions, issues and mistakes of various BIPV projects are touched, whereas special emphasis is provided on BIPV engineering procedures, system design complexity, as well as shading issues and differentiation of shading according to their origin.