Solar PV is an important element in global energy transformation. Current PV capacity has to be increased several times for successful implementation, with buildings playing a key role. In theory, buildings provide a more economically useful surface area than the required increase in PV capacity demands. However, building-integrated photovoltaics (BIPV) places high demands on solar PV module design in that a conflict often exists between sophisticated design, high module efficiency and low costs.
A joint project funded by the German Federal Ministry for Economic Affairs and Energy, SCHMID and Fraunhofer ISE has examined the design limitations of BIPV as well as the existing standards, laws and technical regulations. The project also evaluated the effects of each of these factors on the module design with Fraunhofer ISE investigating the building stock and the associated market potential.
Based on the market potential and the design requirements, Fraunhofer ISE and SCHMID developed two new customised production line concepts for the flexible series production of BIPV modules. From the very start of the project, the production line concepts considered the modifications necessary for building integration, such as module format, glass colour and encapsulation material, different thicknesses of glass and variations in the solar cell matrix. The production lines are also equipped with additional transfer stations which can be rapidly adapted to different module designs.
The one-year project focused on industrial applicability, with cost calculations carried out for all of the developed production solutions. This enabled a cost-saving series fabrication while also offering a wide range of freedom in module design. SCHMID and Fraunhofer ISE found that the developed production lines can reduce the costs of BIPV by 35 percent. The new BIPV production concept is now available to interested partners.
“Our results showed that the combination of series production and freedom of design do not comprise each other” said Stefan Sellner, project head at SCHMID. “We also demonstrated that we can reduce the costs by an average of 35 percent compared to conventional manufacturing processes of BIPV modules. A flexible, yet cost competitive, BIPV production that also accommodates the various needs of architects, module producers and system integrators at the same time is now possible.”
Max Mittag, a scientist at Fraunhofer ISE, added that potential uses for BIPV modules with customised designs are, for example, office buildings with large area facades.