Swiss solar project manager, Felix & Co Windgate, added 109 kW of building integrated PV (BIPV) capacity to the facade of a property owned by Swiss retailer Lehner Versand, part of a larger renovation project that increased the building height by 12 meters.
The addition provided 866 m2 of screen-printed colored glass modules supplied by Ertex Solar, an Austrian module manufacturer. The new active solar facade has a sequins-like appearance enabled by the curtain wall sub-structure and the colored glass-glass panels. “By incorporating varying inclinations in the façade elements, the building's envelope is elegantly designed. This also creates an aesthetic play of light, giving the structure a natural vibrancy and rich coloration,” a spokesperson for Windgate told pv magazine.
The building already had a rooftop plant with conventional silicon solar panels, which combined with the new installation now provides 114,560 kWh annually, providng 24.5% of the building’s needs, according to a statement by the 2024 Schweizer Solarpreis.
There are practical benefits for this type of installation that features modules installed on the south, east, and west-facing facades, especially in winter, according to Windgate's spokesperson. “Generally, the energy yield from facade systems is lower than that of rooftop installations due to the less favorable angle of sunlight incidence compared to the PV modules on the roof. However, there is a significant advantage: the shallower sunlight angles during winter are utilized more effectively, enhancing energy supply reliability in winter and increasing self-consumption,” they said.
The project team achieved the sequins effect by varying the inclination direction of the modules installed on the curtain wall sub-structure. It was a solution developed, engineered, and manufactured by Ecolite, a Swiss building material company. The brackets, which support the panels at four different angles, were delivered as pre-assembled sub-structures and fixed to steel spans on site.
“Our task was to adapt an existing suspension system to the requirements of the Lehner Versand project in such a way that the large spans between the vertical steel girders of the extension could be spanned and then the suspension for the tilted PV modules could be mounted on it correctly in terms of dilatation and statics,” Samuel Bregenzer, founder and manager of Ecolite, told pv magazine.
The project was recently recognized by the 2024 Schweizer Solarpreis in the building renovation category.
