Optical modelling and energy-yield assessment of UV down-shifting layers for high-efficiency TOPCon solar modules

Lipovšek, Benjamin (author), Tomšič, Špela (author), Rochat, Nicolas Frédéric (author), Marthey, Lison (author), Li, Hengyu (author), Escarre Palou, Jordi (author), Petri, Delphine (author), Levrat, Jacques (author), Ollagnon, Florian (author), Despeisse, Matthieu (author), Haug, Franz-Josef (author), Faes, Antonin (author), Ballif, Christophe (author), Topič, Marko (author)

The transition of the photovoltaic industry towards n-type TOPCon technology has increased interest in ultraviolet (UV)-induced degradation mechanisms affecting both solar cells and module materials. While conventional UV absorbers can mitigate degradation, they also reduce photocurrent generation by removing a portion of the incident solar spectrum. Luminescent UV down-shifting (UVDS) layers offer an alternative approach by absorbing harmful UV photons and re-emitting them at longer wavelengths, where silicon solar cells exhibit higher conversion efficiency. In this work, we present an experimentally calibrated and validated comprehensive optical modelling framework for simulation of UVDS layers integrated into n-type TOPCon solar cells and modules. The model was calibrated using experimentally characterized UVDS layers based on luminescent dyes embedded in a polyolefin elastomer matrix and validated through comparison with measured external quantum efficiency data. Parametric simulations identified dye concentration and photoluminescent quantum yield as the key parameters governing UVDS performance. The results show that UVDS layers capable of absorbing approximately 90% of incident UV radiation introduce photocurrent losses below 1%, while providing more than 2% photocurrent gain relative to conventional UV-blocking layers with comparable absorption characteristics. The validated modelling framework was further applied to long-term energy-yield simulations and realistic module geometries, demonstrating its usefulness for the analysis and optimization of UVDS-enhanced photovoltaic devices and modules.

• Language: English
• Keywords: luminescent UV down-shifting, TOPCon solar cells, optical modelling, photoluminescence, spectral conversion, energy yield, UV-induced degradation
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2027
• Number of pages: 11 str.
• Numbering: Vol. 309, art. 114748
• PID: 20.500.12556/RUL-189589
• UDC: 621.383.51
• ISSN on article: 1879-3398
• DOI: 10.1016/j.solmat.2026.114748
• COBISS.SI-ID: 294522883
• Publication date in RUL: 09.10.2026

Record is a part of a journal

• Title: Solar energy materials and solar cells
• Shortened title: Sol. energy mater. sol. cells
• Publisher: Elsevier
• ISSN: 1879-3398
• COBISS.SI-ID: 23165957

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: luminiscenčna UV pretvorba navzdol, TOPCon sončne celice, optično modeliranje, fotoluminiscenca, spektralna pretvorba, energijski izplen, UV degradacija

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0415
• Name: Fotovoltaika in elektronika

• Funder: EC - European Commission
• Project number: 101136094
• Name: Sustainable Photovoltaics Integration in buildings and Infrastructure for multiple applications
• Acronym: SPHINX