Analysis of light collection in GaAs/Si HJT four-terminal solar cell system based on spectral splitting and polymeric wedged optics: a role for diffusive lateral supports

Year: 2025

Authors: Ahmadi M., Pagano R., Matera F., Bonomo M., Galliano S., Benesperi I., Barolo C., Fontani D., Morabito F., Farina A., Pietralunga SM., Lombardo SA.

Autors Affiliation: CNR Inst Microelect & Microsyst, VIII Str 5, I-95123 Catania, Italy; Univ Catania, Dept Phys & Astron, Via Santa Sofia 64, I-95123 Catania, Italy; Univ Turin, NIS Interdept Ctr, INSTM Reference Ctr, Dept Chem, Via Quarello 15-A, I-10135 Turin, TO, Italy; ICxT Interdept Ctr, Via Quarello 15-A, I-10135 Turin, TO, Italy; CNR Natl Inst Opt, Largo Fermi 6, I-50125 Florence, Italy; CNR Inst Photon & Nanotechnol, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy; Univ Roma La Sapienza, Dept Basic & Appl Sci Engn, Via Castro Laurenziano 7, I-00161 Rome, Italy; Inst Sci Technol & Sustainabil Ceram ISSMC CNR, Via Granarolo 64, I-48018 Faenza, Italy.

Abstract: In this work a system combining a GaAs and Si heterojunction cells with optical components in a four-terminal solar cell configuration is presented. This system achieves optical low gain non-imaging asymmetric concentration and spectral splitting in order to enhance energy conversion specific to each cell, and represents a promising pathway to overcome the limitations and improve the efficiency of conventional photovoltaic systems. The split of the solar spectrum is realized by integrating into the system a specifically designed polymeric dielectric prism with light waveguide capability and high transmittance, coupled with a tailored dichroic mirror that reflects wavelengths shorter than 805 nm and transmits longer ones. In view of optimizing its performance, we critically investigate the optical performance of each component and of the system as a whole, at different light source incident angles and different colors of the side covers in a controlled indoor test environment. Moreover, outdoor tests at four fixed system orientation angles and for different side color cover cases have been performed. 4T system efficiency is studied both in indoor with a solar simulator and in outdoor under natural sunlight. The experimental results provide some clear indications to improve the system’s performance, highlighting the importance of the incident angle of the source and of color of the covers to boost light collection.

Journal/Review: SOLAR ENERGY

Volume: 301      Pages from: 113934-1  to: 113934-11

More Information: M.A, R.P, F. M., A. F., D. F., S, M. P, and S. A. L gratefully acknowledge funding support from the PON Ricerca e Innovazione 2014-2020 Italian project ARS01_00519 BEST-4U. M.A, R.P, F. M., and S. A. L also acknowledge the IPHOQS Infrastructure Integrated Infrastructure Initiative in Photonic and Quantum Sciences (IR0000016) and the Research Infrastructure Beyond-Nano co-funded by Regione Sicilia (D.D.G. 2929/5S) and by Italian Ministry of University and Research (Decree 2510/2019) . They also thank the invaluable graphic and editing help received from Michel Piliougine Rocha and Bahareh Sadat Jalilian. M.B., S.G., I.B. and C.B. acknowledge support from the project CH4.0 under the MUR (Italy) program Dipartimenti di Eccellenza 2023-2027 (CUP: D13C22003520001) . I.B. acknowledges support from the PNA4Energy project, funded under the MUR (Italy) program PNNR M4C2 Initiative 1.2: Young Researcher-Seal of Excellence (CUP: D18H22001950007) , and thanks ICxT at the University of Turin for providing the 3D printer used to fabricate the wedge supports. S.G. acknowledges the project NODES which has received fundings from the MUR (Italy) -M4C2 1.5 of PNRR with grant agreement no. ECS00000036. M.B., S.G., I.B. and C.B. are also indebted with Demak Polymers s.r.l. for providing the precursors for the formulation of
KeyWords: GaAs/Si HJT four-terminal solar cells; Spectral splitting; Polymeric wedged prism; Low-gain non-imaging asymmetric optical; concentrator; Indoor and outdoor photovoltaic solar system; characterization
DOI: 10.1016/j.solener.2025.113934