Our technical focus is crystalline silicon based photovoltaic power generation, in durable roofing tiles that mount directly to the structural framing, said System Photonics chief executive officer Gianluca Aiazzi. Because it’s a high volume application, our strategy was to reduce module labor costs through advanced automation, and then seek further cost-per-watt efficiencies and module manufacturing advantages through ongoing materials science.
System Photonics’ roofing tiles feature power generating cells embedded between two 35-mil sheets of clear DuPont™ PV5300 Series encapsulant, mounted onto individual ceramic tiles about 1 meter wide. The BIPV roofing tiles are topped with low-iron glass, also held in place by the new encapsulant.
The completed assembly is pressed together and heat-sealed using automated vacuum laminators with robotic feeds. The new ionomer-based encapsulant has been instrumental in designing the manufacturing process for speed, reliability and efficiency.
Attilio Russo, chief technology officer for System Photonics, guided development of the new design after discovering a stiffer safety glass interlayer product from DuPont called SentryGlas. Follow up discussions with DuPont identified that similar benefits could be gained in PV from using DuPont™ PV5300 encapsulant sheets, which are 5 times tougher and up to 100 times stiffer than the PVB and EVA sheets more commonly used as encapsulants.
We needed a material that could add to module strength and support automated sheet handling equipment, explains Russo. The encapsulant needed to be easily managed and aligned across all steps of the production process. Other encapsulant sheets were too floppy and elastic, making them hard to handle; so we immediately saw production speed advantages with the DuPont™ PV5300 sheet.
System Photonics designed its ROOF Collection tiles with open, frameless edges for architectural elegance and simplicity. Compared with other encapsulants we tested, the stiffer DuPont™ PV5300 ionomer sheet also made modules more impact-resistant and much more durable in weather-exposed open edges, notes Russo.
The frameless roofing tiles are offered in 24 attractive colors, selected for residential architectural appeal. System Photonics plans to continue its advance of BIPV technology by developing lighter modules with thinner sun-facing materials, relying further on the structural and impact strength of the new encapsulant.
