Abstract
A polymer composite material system and a process for encapsulation of thin film solar cells were developed for profiled roofing elements, in view of building-integrated photovoltaic (PV) applications. Amorphous silicon cells were deposited on a polyethylene naphthalate film and encapsulated with additional polymer layers in the form of a flat laminate using industrial processes. The process technology developed in this work included a pre-forming step of the PV laminate and a moulding step of a glass fibre-reinforced polyester composite. These two steps were optimised using thermo-elastic analyses, with attention paid to laminate designs and process windows compatible with the thermo-mechanical limits of the fragile active PV layers. A demonstrator with standard 1.0 m×1.8 m corrugated roofing profile, a weight of 6.3 kg and 60 W of output power was produced. The long-term endurance of the conformal modules was also validated using humidity-freeze, damp-heat and water immersion tests.
Acknowledgements
The authors acknowledge the Swiss Commission for Technology and Innovation (CTI, project 9903.1 PFIW-IW) and the company VHF Technologies SA for financial support.
Notes
†Parts of this work were presented at the 21st International Photovoltaic Science and Engineering Conference, PVSEC21, November 28–December 2, 2011, Fukuoka, Japan.