- News
13 February 2014
Avancis achieves 16.6% efficiency record for encapsulated CIS thin-film PV modules
Avancis GmbH of Torgau, Germany, a subsidiary of Saint-Gobain of Courbevoie, France since autumn 2009 which manufacturers copper indium selenide (CIS) thin-film photovoltaic modules, has achieved a new efficiency record for encapsulated thin-film modules. On a 30cm x 30cm cadmium (Cd)-free CIS solar module, the firm has achieved a peak value of 16.6%, independently confirmed by the US Department of Energy's National Renewable Energy Laboratory (NREL). Avancis set the last externally certified efficiency record of 15.1% in 2011.
The aperture efficiency of 16.6% for the champion module was certified by NREL in January and will be listed in the official record efficiency table in the next edition of the journal Progress in Photovoltaics: Research and Applications (Solar Efficiency Tables, Table II: Confirmed terrestrial module efficiencies). Together with the 20.8% efficiency for a laboratory cell reported by Germany’s ZSW (Center for Solar Energy and Hydrogen Research — Baden-Württemberg), the result demonstrates the extraordinary potential of CIS-based thin-film technologies, says Avancis.
“A transfer of the pilot process to production would lead to an impressive module performance of nearly 160Wp of the approximately 1m2-sized PowerMax modules,” reckons Dr Jörg Palm, head of process development at Avancis. “The very good homogeneity of the CIS absorber properties based on production dimensions of 158cm x 66cm were demonstrated by the minor deviation of 0.15% absolute between different 30cm x 30cm modules from the same full-size absorber,” he adds.
The 30cm x 30cm champion module used a mass-produced CIS absorber from Avancis’ second factory in Torgau, followed by buffer processing at the firm’s R&D center in Munich.
The improvement in efficiency is based on optimization of the buffer layer with respect to the InxSy energy bandgap, band matching, and in particular transmission in the short-wavelength range. In addition, the transmittance and sheet resistance of the sputtered ZnO:Al front contact was optimized and the dead area between the series-connected cells was reduced by using picosecond laser processes.
Avancis raises monolithic thin-film PV module efficiency record to 15.5%