The photovoltaic effect is a phenomenon involving the creation of an electromotive force in a solid under the influence of solar radiation. The photovoltaic effect is used in photovoltaic cells, devices that produce electricity directly from solar radiation. Photovoltaic cells are the basic building blocks of solar cells (also called photovoltaic modules or panels). Based on solar cells, photovoltaic installations are built. The table in Fig. 1 shows some dates related to the discovery of the phenomenon and the modifications made until the beginning of the 21st century (figures in the table are own elaboration, photographs are from: [1], [2], [3], [4], photo of satellite on a base [5]; free license photographs).