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 photovoltaic panels over the years Occupied surface Hours of daylight during the year.

Resources:
Series solar panels connection Parallel solar panels connection Module - string - array Solar zenith Solar azimuth Solar declination.

The app also contains a very useful form.