Solar facade with frameless design

German research institute Helmholtz Zentrum Berlin (HZB) has commissioned a 50 kW solar facade at its new research building in Adlershof, Berlin.

The facade was built with 360 CIGS thin-film solar modules with a power output of 135 W each, provided by an undisclosed manufacturer and installed on the west, south and north sides of the building.

The main technological feature of the installation, according to its creators, is the concealed suspension technology used. “It enables a frameless design without additional edging at the edge of the module,” the research institute said in a statement. “This makes it possible to combine the modules ideally with the metal curtain wall of the building.”

The modules are installed in landscape format, with each panel having two horizontal back rails which are glued on the back-side glass, without the need for frames and screws. The installers mounted two additional vertical rails on these back rails, which also contain two rods that are used to hook the modules into a preliminary-installation, vertical sub-construction mounted on the wall at an earlier point. The modules are hung in front of the cladding using a rail system so that a small air space is created between the module and the thermal insulation.

The new facade will be used not only to power the building but also as a real laboratory for PV research. For this purpose, the HZB researchers installed 72 temperature, ten irradiation and four wind sensors. The devices are intended at evaluating environmental factors, weather conditions, and compass directions.

“The extensive measurement technology enables new insights into the real behavior of solar modules in a facade in different seasons and weather conditions, over a long period of time,” said Björn Rau, the head of the BAIP – the consulting office for building-integrated photovoltaics (BIPV) at HZB.