The conventional pv system in general uses sc - si or mc - si solar cell module as the element for solar energy conversion , for which have comparatively higher conversion efficiency . available in pv market , the typical efficiencies under stc are 14 % , 12 % and 7 % for sc - , mc - and nc - si solar cell modules , respectively 传统的光伏发电系统通常采用单晶硅或多晶硅电池组件作为太阳能转换器件,这是因为它们比非晶硅太阳电池具有更高的光电转换效率,在标准测试条件下三种太阳电池组件的典型光电转换效率分别为: 14 % 、 12 % 、 7 % 。