Analysis of Fundamental Light Receiving Characteristics of Spherical Solar Cells

The spherical solar cells are claimed to have some advantageous characteristics superior to those of the ordinary planar solar cells. The most significant one is that the spherical solar cells have no directivity to light. This paper examines the characteristics based on geometrical consideration. It is proved that a single spherical cell has no directivity as a whole. In practical use, many cells are used in an array configuration, where an individual cell receives the shadows casted by other cells around it. The adjacent shadows, so named in this paper, causes directivity. Their effects are evaluated geometrically and the theoretical consideration is verified by experiments.