Passive Solar Tracking for PV Window Shutters

Building-integrated photovoltaics (BIPV) offer enormous potential for decentralized renewable energy generation in urban areas. While rooftops are increasingly utilized, façades remain a largely untapped resource for solar power.

Fixed PV systems on façades cannot capture the maximum possible yield as the solar incidence angle varies throughout the day. Conventional motorized tracking systems are unsuitable for building applications due to complexity, cost, and maintenance requirements.

The NPV-Balken project addresses this gap by developing a novel, fully passive tracking concept. Using phase change materials (PCM) that expand when heated by sunlight, we create controlled rotational movement of PV slats without any external power, sensors, or control systems.

This technology can replace conventional window shutters while generating clean energy – making solar power accessible even for apartments without balconies or roof access.