The electricity production of a PV system
depends on external (environmental conditions) and internal (technology,
layout of the system) parameters.
Shadows on the modules (also if they appear only at certain times of day) reduce significantly the gain of the whole system and should be avoided.The map below represents the yearly sum of global irradiation on a horizontal (inclined) surface. Alternatively the maps represent solar electricity [kWh] generated by a 1kWp system per year with horizontal (or inclined) modules.
To determine the PV electricity generation potential for a particular site, it is important to assess the average total solar energy received over the year.