A study on the influence of the albedo spectrum on the bifacial GaAs/c-Si heterojunction tandem solar cell using computer modelling. (October 2021)

• Record Type: Journal Article
• Authors: Lee, Sunhwa; Trinh, Thanh Thuy; Pham, Duy Phong; Kim, Youngkuk; Cho, Eun-Chel; Kang, Hokwan; Dang, Nam Nguyen; Dao, Vinh-Ai; Park, Jinjoo; Yi, Junsin
• Is Part Of: Solar energy. Volume 227(2021)
• Page Start: 490
• Page End: 496
• Publication Date: 2021-10
• Subjects: GaAs solar cells -- c-Si heterojunction -- GaAs/Si tandem -- Bifacial tandem solar cell -- Albedo reflection; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2021.07.073
• Languages: English
• ISSNs: 0038-092X

Abstract

Graphical abstract: Highlights: We propose two- and four-terminal GaAs/c-Si HJ tandem solar cells with albedo. The GaAs/c-Si HJ tandem cell with albedo is more efficient than the individual sub-cells. The computer modeling is utilized to optimize the performance. The η ∗ value of the two-terminal GaAs/c-Si HJ tandem cell is of 40% with RA of 30%. The η ∗ value of the four-terminal GaAs/c-Si HJ cell is of 40.31% with RA of 30%. Abstract: Recently, III-V/c-Si heterojunction (c-Si HJ) tandem solar cells received considerable attention owing to their high conversion efficiency. In a tandem configuration, current matching has a significant impact on conversion efficiency. Specifically, in the two-terminal tandem structure, the sub-cell with the lowest current density ( Jsc ) dominates the Jsc of the tandem cell, which in turn, dominates the overall conversion efficiency of the tandem device. Meanwhile, in a four-terminal tandem structure, although the current matching condition is not mandatory, an efficient light distribution is necessary to achieve high efficiency in each sub-cell, which in turn results in a high efficiency of the tandem cell. Herein, we propose two- and four-terminal GaAs/c-Si HJ tandem solar cells using effective albedo reflections ( RA ) to overcome the aforementioned limitations. As RA increased, the current density of the c-Si HJ solar cells increased from 3.07 mA/cm 2 ( RA = 10%) to 39.90 mA/cm 2 ( RA = 100%) on the rear side of the cell, thereby, overcaming the existing current density limit. In addition, we investigated the tandem structures via simulation to provide a practical direction for achieving high efficiency. Finally, normalised outputs of 40.00% and 40.31% were achieved for the two-terminal and four-terminal GaAs/c-Si HJ bifacial tandem solar cells, respectively, with a real-life albedo from common ground surfaces, such as sand.