Perovskite/silicon tandems for a high performance

Relevance

The high efficiency offered by tandem PV contributes to reducing overall PV system costs, and is important to reduce the area required for PV power generation. Both aspects support the transition to a society using primarily renewable energy.

Market

The international technology roadmap for photovoltaics (ITRPV) foresees that tandem PV based on crystalline silicon (c-Si) will make rapid progress towards industrial implementation, and will have obtained a significant market share by 2025. Because of the limited available area for PV and importance of rooftop PV, tandem PV is very suitable for the Netherlands.

Technologies

Hybrid organic-inorganic perovskite thin film solar cells are the primary candidate technology to be paired with c-Si to construct the tandem, while other candidates are also under investigation. Research organization Solliance, in which TNO participates, executes an industrial shared research program on perovskite PV technology. TNO together with academic and industrial partners combines the perovskite thin film technology with c-Si technology to create tandem cells and modules. So far an efficiency gain of 5 percentage points over typical industrial c-Si cells was achieved. TNO expects to begin small scale module outdoor tests in 2018. Solliance also looks into fully thin-film-based tandem PV technologies, such as perovskite combined with CIGS.

TNO

Based on its know-how spanning the entire production chain from solar cell to PV system, TNO can provide support and cooperation on topics such as:

• Adaptation of c-Si cell and module technology to suit a tandem application. Examples are specific applications of polySi passivated contact cell technology, and conductive backsheet module technology.
• Integration of cell technologies into a tandem module. Examples are module materials suitable to protect the perovskite solar cells, and design and configuration of the electrical interconnection of the cells.
• Integral tandem device design, characterization, modeling, and optimization. For example, optical analysis and optimization for achieving a high efficiency.
• Accelerated degradation testing, failure analysis, and solutions. Perovskite solar cells require interconnection and encapsulation methods different from standard c-Si technologies. Creating stable long-lifetime tandem modules is an important objective of TNO's research program.
• Performance monitoring, reliable field data, and understanding of energy yield.