Photovoltaic systems represent the future, this app brings together simple and quick calculations to make the most of solar energy. Main: Efficiency of solar panels, Air mass coefficient, Fill factor, Sun position, Optimal tilt angle, Solar radiation on a tilted surface, Solar cell temperature, Effect of temperature on the photovoltaic module, Compass, Tilt, Size of the solar cable (DC), Protection device sizing, String sizing, Short-circuit current of strings, Choice of inverter, Decay of phot