Realizing high photovoltaic efficiency with parallel multijunction solar cells based on spectrum-splitting and-concentrating diffractive optical element  

作　　者：王进泽 黄庆礼 许信 全宝钢 罗建恒 张岩 叶佳声 李冬梅 孟庆波 杨国桢 

机构地区：[1]Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences [2]Key Laboratory for Renewable Energy, Institute of Physics, Chinese Academy of Sciences [3]Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences [4]Laboratory of Microfabrication, Institute of Physics, Chinese Academy of Sciences [5]Beijing Key Laboratory for THz Spectroscopy and Imaging, Key Laboratory of THz Optoelectronics, Ministry of Education [6]Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences

出　　处：《Chinese Physics B》2015年第5期329-334,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.91233202,21173260,and 51072221);the National Basic Research Program of China(Grant No.2012CB932903)

摘　　要：Based on the facts that multijunction solar cells can increase the efficiency and concentration can reduce the cost dramatically, a special design of parallel multijunction solar cells was presented. The design employed a diffractive optical element （DOE） to split and concentrate the sunlight. A rainbow region and a zero-order diffraction region were generated on the output plane where solar cells with corresponding band gaps were placed. An analytical expression of the light intensity distribution on the output plane of the special DOE was deduced, and the limiting photovoltaic efficiency of such parallel multijunction solar ceils was obtained based on Shockley-Queisser＇s theory. An efficiency exceeding the Shockley--Queisser limit （33%） can be expected using multijunction solar cells consisting of separately fabricated subcells. The results provide an important alternative approach to realize high photovoltaic efficiency without the need for expensive epitaxial technology widely used in tandem solar cells, thus stimulating the research and application of high efficiency and low cost solar cells.Based on the facts that multijunction solar cells can increase the efficiency and concentration can reduce the cost dramatically, a special design of parallel multijunction solar cells was presented. The design employed a diffractive optical element （DOE） to split and concentrate the sunlight. A rainbow region and a zero-order diffraction region were generated on the output plane where solar cells with corresponding band gaps were placed. An analytical expression of the light intensity distribution on the output plane of the special DOE was deduced, and the limiting photovoltaic efficiency of such parallel multijunction solar ceils was obtained based on Shockley-Queisser＇s theory. An efficiency exceeding the Shockley--Queisser limit （33%） can be expected using multijunction solar cells consisting of separately fabricated subcells. The results provide an important alternative approach to realize high photovoltaic efficiency without the need for expensive epitaxial technology widely used in tandem solar cells, thus stimulating the research and application of high efficiency and low cost solar cells.

关 键 词：diffractive optical element SPLIT CONCENTRATION MULTIJUNCTION 

分 类 号：TM914.4[电气工程—电力电子与电力传动]