A simple PV array area finder, calculating needed square meters based on user inputs, as described in the table below.

Description Input
1
Location latitude in degrees.
Can be found from Google Maps.
2
Irradiation in watts per squaremeters.
Can be found and used from page #3.
3
Daily energy usage in watthours.
Can be found and used from page #1.
4
PV module maximum power point efficiency
in percent. (Sometimes called conversion efficiency.)
Can be found in PV module datasheet.

Estimated PV array surface area:
[ m^(2) ]
Note:
This page algorithm is assuming that the incident sun angle relative to the PV module has an average value of 5 degrees, as well as neglecting losses from a fixed azimuth angle and high operating temperatures.

Comments and improvement suggestions are always welcomed and appreciated.