Symposium EN08-Low-Cost Tandem Photovoltaic Cells

This symposium will cover the science and technology of wide-bandgap (1.5–2.0 eV) photovoltaic cells intended for integration into tandems with silicon or thin-film bottom cells. One materials challenge is designing absorber and contact materials with few recombination-active defects so that high open-circuit voltages—and thus cell efficiencies—are possible. Another, intertwined challenge, is ensuring that the materials are compatible with processing on silicon or narrow-bandgap thin-film bottom cells if a monolithic two-terminal configuration is desired. The materials must also be transparent in the infrared portion of the spectrum so as not to steal current from the bottom cell. In addition, they must be sufficiently robust for insertion into a product warrantied for 25 years, and cost competitive in a market in which 17%-efficient silicon modules now cost <$75/m2.

This symposium solicits abstracts on exciting wide-bandgap top-cell absorber candidates, including perovskite materials, III-V materials such as GaAsP and InGaP, II-VI materials such as MgCdTe and ZnCdTe, and chalcogenides such as CIGS. All aspects of these materials that affect tandem cell performance, from growth to defect characterization to cell performance to reliability, are of interest. Contact materials that passivate the absorber surfaces and selectively extract electrons or holes are also relevant. Abstracts describing top cells employing these materials, bottom cells specifically designed for tandems, or tandems are also solicited, as are abstracts investigating novel configurations for sub-cell coupling.

Topics will include:

Wide-bandgap perovskite absorber materials (intended for use in tandems) and photovoltaic devices
Wide-bandgap polycrystalline II-VI and chalcogenide absorber materials and devices
Wide-bandgap polycrystalline III-V thin-film absorber materials and devices
Epitaxial growth of single-crystal III-V and II-VI materials and devices on silicon
Passivating and carrier selective contact materials for wide-bandgap absorbers
Tandem photovoltaic cells and mini-modules employing silicon or thin-film bottom cells
Modeling and demonstration of tandem photovoltaic device arrangements, including two-terminal, four-terminal, and spectrum-splitting
Silicon and thin-film (e.g., perovskite, II-VI, chalcogenide) materials and devices tuned for use as bottom cells in photovoltaic tandems
Reliability and degradation of top cells and tandem cells
Cost-modeling of tandem solar cells

Invited Speakers:

Jinsong Huang (University of North Carolina at Chapel Hill, USA)
Magnus Borgström (Lund University, Sweden)
Chrisoph Brabec (Bavarian Center for Applied Energy Research, Germany)
Kylie Catchpole (Australian National University, Australia)
Tyler Grassman (Ohio State University, USA)
Minjoo Larry Lee (University of Illinois, USA)
Björn Niesen (Ecole Polytechnique Federale de Lausanne, Switzerland)
Marius Peters (Massachusetts Institute of Technology, USA)
Michele Sessolo (Universidad de Valencia, Spain)
Henry Snaith (University of Oxford, United Kingdom)
Ayodhya Tiwari (Swiss Federal Laboratories for Materials Science and Technology, Switzerland)
Emily Warren (National Renewable Energy Laboratory, USA)
Yong-Hang Zhang (Arizona State University, USA)
Sam Stranks, University of Cambridge, United Kingdom (University of Cambridge, United Kingdom)