Perovskite-silicon solar cell research collaboration hits 25.2% efficiency
Perovskite-based tandem solar cells can achieve now efficiencies better than 25%. © HZB
A 1 cm2 perovskite silicon tandem solar cell achieves an independently certified efficiency of 25.2 %. This was presented this week at an international conference in Hawaii, USA. The cell was developed jointly by HZB, Oxford University and Oxford PV - The Perovskite CompanyTM.
"Perovskite-based tandem solar cells can use light particularly efficiently and therefore offer the opportunity to achieve even higher efficiencies. That is why we have significantly expanded our expertise with the new Helmholtz innovation laboratory HySPRINT," says Prof. Dr. Rutger Schlatmann, Director of the Competence Center Thin Film and Nanotechnology for Photovoltaics Berlin (PVcomB) at HZB. "In our cooperation with Oxford PV, we aim to further optimize perovskite silicon tandem cells, demonstrate their scalability and facilitate their integration into large-area solar modules. For this new result we have optimized our high-efficiency silicon heterojunction bottom cell and developed an optical adaptation to the top cell using a very specific SiOx intermediate layer".
At the World Conference on Photovoltaic Energy Conversion, WCPEC-7 in Waikoloa, Hawaii, tandem solar cells involving perovskites were an important topic: two records have been presented with 25.2% certified efficiency: one from the group of Prof. Christophe Ballif at EPFL/CSEM and one from the consortium HZB/OxfordPV/Oxford University, presented by HZB scientist Dr. Bernd Stannowski. The third one, with 25.0% certified efficiency is a tandem cell developed by an HZB team headed by Dr. Steve Albrecht.
Oxford PV was established in 2010 and has had a close working relationship with Professor Snaith’s research group at the University of Oxford. In January 2018, Oxford PV announced its collaboration with HZB, the leading German research centre focused on energy materials research.
Press Release by Oxford PV
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