ИСТИНА

There are two reasons to use bifacial solar cells in concentrator systems. First, some optical concepts (for example, TRAXLETM from Poulek Solar) are designed in such a way that both sides of the cell are illuminated, therefore bifacial cells in these systems produce more electricity than monofacial cells. The second reason, as is shown in this paper, is that bifacial cells are preferrable for application in concentrator systems. Therefore the purpose of the present work was to develop a bifacial concentrator solar cell for application in low-concentrator system. Developed solar cell is based on the Laminated Grid Cell (LGCell) Indium-Fluorine-Oxide/(n+pp+)Cz-Si/Indium- Tin-Oxide structure. LGCell was made of routine crystalline Cz silicon and the front/rear efficiencies of above 17.7%/13.3% under 1-6X illumination were achieved. This result is unique because, to our knowledge, no results concerning the development of a bifacial concentrator solar cell have been reported until now. Besides, we have shown that under intense illumination, the open-circuit voltage of the bifacial cell decreased significantly less (158 mV after 500 s of illumination) compared to the monofacial cell (196 mV), i.e. the benefit amounts up to ~ 40 mV. This result definitely indicates that in the case of bifacial cell, the degradation of cell performance caused by the temperature increase under concentrated light is considerably less compared with monofacial cell.