The main driving forces for the realization of the BIPV façade in the Fronius office building was the architect himself, who was strongly supported by the customer Fronius. At the end of 2010 the architect considered to integrate vertically movable sunshades with solar cells into the façade of the new designed Fronius building. Several options and technologies have been investigated and compared with each other in the development phase. In this phase, the company ertex solartechnik GmbH provided a lot of samples with different layouts to help the architect and the customer in the decision-making process. Next to crystalline silicon cell technologies, also the thin film technologies were considered because of their very homogenous appearance.  Also semi-transparent cells (with small holes in the wafer) were considered as an option. In the end both, thin film and semitransparent technologies did not meet the customer’s expectations regarding the energy output and cost aspects. Also, the initially planned movable solution using sunshades was skipped concerning the high costs and requirements for the structure and also the glass, due to special requirements related the glass thickness, e.g. if the glass is fixed only on the short side of an element, the glass thickness would need to increase dramatically which is amongst others related to the wind loads. Taking into consideration all of these variation possibilities and options, finally, all involved stakeholders, especially the architect and the customer/user were happy to have a “full size” solution from ertex solartechnik GmbH allowing a quick and high quality installation of the BIPV system. (Dieter Moor, ertex solartechnik GmbH.)