A solar cell may include an electrically conducting substrate, a plurality of nanowhiskers extending from the substrate and a transparent electrode extending over free ends of the nanowhiskers and making electrical contact with them. Each nanowhisker may have a column with a diameter of nanometer dimension. The column may include a first p-doped semiconductor lengthwise segment and a second n-doped semiconductor lengthwise segment. The first and second semiconductor segments may have an interface between them, which forms a p-n junction. The nanowhiskers may be encapsulated in a transparent material.