High Efficient Very Large Thin Film Silicon Photovoltaic Modules (HELATHIS)

Abstract

In this paper we present the European project HELATHIS created by the Consortium formed by the a- Si module manufacturer T-Solar Global S.A (Spain), the European branch of the multi-national TCO glass producer AGC (Belgium) and the solar energy research groups: Inst. for Energy Research-5 at the Research Center Juelich (Germany), the Debye Institute for Nanomaterials Science at the Utrecht University (The Netherlands) and the Dept. of Applied Physics and Optics at the University of Barcelona (Spain). The Consortium has identified optical light confinement as a key point to increase module efficiency and results of the work realized in the five experimental work packages during the first nine months of the project are presented here. In Work Package (WP) 2 -Glass front surface-, first results for the preparation of anti-reflection coatings by a sol-gel process are presented achieving a reflection reduction of about 1.5%. In WP3 -Glass/TCO interface- the evolution of the T-Solar module efficiency with AGC AN10 TCO glass is shown, demonstrating stabilized module efficiency over 7% for single junction a-Si modules. In WP4 -Intermediate reflector- various development strategies to improve silicon thin film tandem solar cell structures are presented. In WP5 -Back reflector- we found more than 5% increase of current density in the TSolar standard solar cell by exchanging the Al layer by an Ag-layer in the back reflector structure. Finally, in WP6 – Advanced characterization methods- results of optical properties of industrial and laboratory TCO’s are presented.