This paper overviews photovoltaic R&D projects in Japan. Recently, world‐record and second highest efficiencies of various types of solar cells have been demonstrated under the New Energy and Industrial Technology Development Organization Project: 44.4% (under concentration) and 37.9% (under 1 sun) InGaP/GaAs/InGaAs inverted metamorphic 3‐junction solar cells by Sharp, 26.7% single crystalline Si heterojunction back‐contact solar cell by Kaneka, 22.3% copper indium gallium selenide solar cell by Solar Frontier, a‐Si/μc‐Si/μc‐Si thin‐film triple‐junction solar cell with stabilized efficiency of 14.0% by AIST, 11.9% dye‐sensitized solar cell by Sharp, and 11.2% organic solar cell by Toshiba. This paper also presents efficiency potential of high‐efficiency and next‐generation solar cells analyzed by considering external radiative efficiency, open‐circuit voltage loss, and fill factor loss. Efficiency potential of crystalline Si, GaAs, III‐V compound 3‐junction and 5‐junction, CIGSe, CdTe, CZTS(Se), multiquantum well, and quantum dot and perovskite solar cells is shown to be 28.5%, 29.7%, 40%, 43%, 26.5%, 26.5%, 20%, 25.8%, and 24.9% under 1 sun, respectively.

中文翻译：

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高效和下一代太阳能电池的效率潜力分析

本文概述了日本的光伏研发项目。最近，在新能源和工业技术开发组织项目下，已证明各种类型的太阳能电池的世界纪录和第二高效率：InGaP / GaAs / InGaAs倒置变质为44.4％（在浓度下）和37.9％（在1个太阳下）。 Sharp的3结太阳能电池，Kaneka的26.7％单晶Si异质结背接触太阳能电池，Solar Frontier的22.3％铜铟镓硒太阳能电池，a-Si /μc-Si/μc-Si薄膜三重太阳能电池结太阳能电池，AIST的稳定效率为14.0％，Sharp的染料敏化太阳能电池的稳定度为11.9％，东芝的有机太阳能电池的稳定度为11.2％。本文还介绍了通过考虑外部辐射效率来分析的高效太阳能电池和下一代太阳能电池的效率潜力，开路电压损耗和填充因数损耗。晶体Si，GaAs，III-V化合物3结和5结，CIGSe，CdTe，CZTS（Se），多量子阱以及量子点和钙钛矿太阳能电池的效率潜力分别为28.5％，29.7％，40在1个阳光下分别为％，43％，26.5％，26.5％，20％，25.8％和24.9％。