Generally, to ensure that they reflect as little light as possible and thus prevent energy loss, solar cells are textured using an alkaline bath that forms a rough surface on which pyramids are randomly distributed. Recently, researchers have obtained a record efficiency of 22.1% with silicon solar cells that incorporate black silicon on the front of the cell. 

Traditional solar cells are thick in order to reduce the loss of energy caused by the reflectance of solar cells, while black silicon allows very thin silicon cells to be used, lowering production costs and saving silicon. Nonetheless, incorporating black silicon makes the loss of solar energy to almost zero, which significantly increases the yield of almost 4% compared with traditional solar cells. This extra improvement in efficiency would allow a refrigerator, for example, to run for a day in a photovoltaic system composed of a 5 m² panel. Moreover, black silicon solar cells can capture solar radiation from lower angles. Thus, more electricity can be generated during the same daylight hours compared with traditional cells. 

Tags :   solar cells    black silicon