Patent Number: 6,294,723

Title: Photovoltaic device, photovoltaic module and establishing method of photovoltaic system

Abstract: Disclosed is a photovoltaic module including a plurality of concentrators each having a light-incident plane and a reflection plane, and photo detectors. Each photo detector is in contact with one of the concentrators. The module is capable of effectively trapping light and effectively generating power throughout the year even if the module is established such that sunlight at the equinoxes is made incident on the light-incident planes not in a perpendicular manner but instead obliquely, for example, in the case where the module is established in contact with a curved plane of a roof, or the like. In this module, each concentrator is formed into such a shape as to satisfy a relationship in which the light trapping efficiency of first incident light tilted rightwardly from the normal line of the light-incident plane in the cross-section including the light-incident plane, reflection plane and photo detector is larger than the light trapping efficiency of second incident light tilted leftwardly from the normal line in the above cross-section. Also, these concentrators are arranged in one direction.

Inventors: Uematsu; Tsuyoshi (Kodaira, JP), Warabisako; Terunori (Nishitama-gun, JP), Yazawa; Yoshiaki (Houya, JP), Miyamura; Yoshinori (Nishitama-gun, JP), Tsutsui; Ken (Nishitama-gun, JP), Muramatsu; Shin-ichi (Kodaira, JP), Ohtsuka; Hiroyuki (Hachioji, JP), Minemura; Junko (Kokubunji, JP)

Assignee: Hitachi, Ltd.

International Classification: F24J 2/06 (20060101); H01L 31/052 (20060101); H01L 31/0236 (20060101); H01L 031/023 (); G02B 003/08 (); G02B 017/00 (); G01C 021/02 (); H01J 003/14 ()

Expiration Date: 09/25/2018