The world’s current largest construction project with building-integrated solar glass elements (BIPV) modules is in Mecca, Saudi Arabia. With vast development and modernization measures, the holy mosque is being expanded to provide space for the rapidly increasing number of visitors. To guide the streams of pilgrims safely to the Kaaba, the central sanctuary, four pedestrian bridges were built, among other things. The pedestrian bridges have a length of 120 meters, are 40 meters high and roofed to provide protection from the desert climate. The roofs span the bridges in a curved form with a radius of approx. 24 meters. The glass elements from SUNOVATION are attached to a very light but particularly strong substructure made of composite materials (carbon and glass fibre fabric).
The solar glass elements themselves are a laminated glass structure in which the solar cells are embedded in an approx. 2mm thick silicone layer. The glasses are each approx. 2m² in size and weigh up to 90 kg. Already during the initial planning of the bridges, architects and clients wanted the use of photovoltaic elements in green, the "color of Islam". A realization of the solar glass surfaces in curved form was not thought of at the beginning, because such products were non-existent.
SUNOVATION first developed glass elements in a variety of green shades and surface effects, which were subjected to an elaborate selection process under different lightening conditions. For this purpose, specially developed design-solar cells in multiple types were combined with different glass finishing processes. In addition to the essential criterion of the module optics, the performance parameters were not to be neglected, so that there were limits to the refinement of the front side of the modules. With SUNOVATIONs unique manufacturing technology, a silicone filling process, and the associated options – many different variants were feasible.
In addition to the homogeneous overall appearance of the green solar glass elements, the aim was to create an edgeless curved glass surface that would continue the Islamic architecture of the overall building with its domed structures and curved elements. The structure, roof shape and design of the pedestrian bridges were to be optimally incorporated into the overall architecture. However, the use of flat glass modules would have resulted in undesirable, angular geometries at the module transition. A continuation of the arched roof shape was made possible only with the curved solar glass elements from SUNOVATION, which were then also chosen in the selection process.
“We qualified for this order because SUNOVATION offers a product concept that is particularly suitable for special applications in architecture, especially the desert climate in Arabia” explains Managing Director Heribert Ley. “For our company, this major project is of course paramount, as we have proven our special capabilities against the established competition.” “Further, this order certainly is an indication of the drive and innovative ability of medium-sized businesses in Germany, of which we are already very proud here in the Bavarian Untermain”, Ley continues.
For this project, a total of 14 different geometries were developed and manufactured by SUNOVATION. Of the 14 geometries, 6 variants are of curved design. The covered roof area of the bridge buildings amounts to approx. 12,800m² and is thus the largest building-integrated solar glass area worldwide to date.
In extensive tests, an independent testing institute confirmed the special suitability of the silicone glass laminate for the desert climate in the Middle East compared to the usual laminating techniques. For cleaning and maintenance purposes, the solar glass elements can be entered with thermally toughened single-pane safety glass. The electricity generated is used 100% for self-consumption in ventilation and cooling systems.
The production time of the approx. 8,000 solar glass elements was approx. 12 months. With means of special transports, the modules for the largest mosque in the world were transported in 35 containers from Germany to Saudi Arabia. The costs for this unique BIPV-Project are in the double-digit million range. The installation of the glass-glass-modules is being carried out by the client Premiere Composite Technologies (PCT) in Dubai. PCT is also a manufacturer of innovative composite structures that enable unique, lightweight designs and has realised many exclusive buildings around the world.
