The use of the bifacial solar cells started in space for additional energy conversion by utilizing the Earth’s albedo. The promise of bifacial Si solar cells for space application is based on a proven energy generation increase of 10-20% when using bifacial solar cells instead of regular Si cells in low earth orbits (LEO). Bifacial solar cells can also be applied for other orbits, when orientation is restricted. Among different types of bifacial cells only Si solar cells with n+-p-p+ structure are used for space applications. High quality bifacial cells are produced by industrial fabrication technology based on the combination of thermal P diffusion for n+ layer doping and B ion implantation with subsequent annealing for p+ layer doping. Fabrication technology optimization resulted in improved bifacial solar cell parameters. The bifacial Si solar cells approach the high efficiency multijunction cells in energy generation ability on LEO. Despite the higher sensitivity to hard radiation of back illuminated bifacial Si solar cells, their advantage due to simultaneous contributions of both cell sides, can be retained for a longer period of time. Keywords: Bifacial, Silicon, Solar Cells. For the full article>>