This final paper contains essential information about solar panels. First, their history and development are described. The solar radiation that is most important for the operation of solar panels is also described. Semiconductor types, energy levels, and other essential semiconductor structures are enumerated. 3 types of solar panels are listed, their advantages and disadvantages and a comparison with each other. The methods of connecting solar panels are explained. PWM and MPPT regulators are used to control charging. Schemes, graphs and described advantages and disadvantages are listed. In Europe, it is estimated by 2030 that renewable energy sources will increase to 45%. Croatia is in a golden environment in terms of renewable sources and there is room for improvement. At the very end of this paper, 2 programs out of many for the use of solar panels are presented. The Cypelec pv systems program shows in a 3D view the installation of solar panels on the surface of the roof. Pvgis is an online tool used to assess the production of solar electricity by a photovoltaic (PV) system.