Excursion: Fraunhofer Center for Silicon Photovoltaics 

Over the past twenty years, photovoltaic technology has advanced at a remarkable pace. Wafer and cell sizes have increased significantly, module areas have grown from around 1.7 m² to up to 3 m², while the cost per module has dropped from about €1500 to roughly €50. At the same time, efficiency levels have risen from 10% to over 24%. New cell technologies such as PERC, TOPCon, HJT, and IBC (back-contact cells) enable higher power densities and uniformly black surfaces (“all-black”), which are of particular interest from a design perspective. Due to the drastic decline in prices, the cost structure of PV systems has shifted. Today, installation, maintenance, and integration determine the overall cost. Large and heavy modules have become an increasing logistical challenge for installation companies – transport, handling, and roof load capacity are now key factors in project planning Current trends focus on lightweight, aesthetically integrated, and high-performance modules. Thinner glass, lightweight laminates, reduced cell spacing (“zero-gap” or “shingled” designs), and anti-reflective or optical optimization layers improve both efficiency and visual quality. The production of PV modules is energy-intensive; however, the energy required for manufacturing is typically offset within one to three years, depending on location and technology. A critical issue is material consumption, particularly the high silver content used in cell conductors. Approximately 10% of global silver demand is attributed to PV production. Researchers are therefore exploring alternatives such as copper, aluminum, or conductive polymers. Recycling also remains a major challenge. PV modules consist primarily of glass, aluminum, and silicon, which are theoretically recyclable. In practice, however, the process is technically complex and economically unattractive. The photovoltaic industry continues to face challenges in balancing efficiency, material use, and aesthetics, as well as in navigating global production structures. While China dominates the mass market, Europe’s opportunity lies in developing customized, high-quality, and design-oriented PV solutions – an approach that is particularly relevant to our project.