Effective irradiation on collectors

What this step does

The row is the light that reaches the cells over the year: the plane irradiation after the threshold, less the horizon, row-shading, soiling and glass-reflection rows, plus the ground reflection on the front of a bifacial row. Multiplied by the module efficiency and the module area it becomes the nominal energy of the array.

The math

$$H_{eff} = H_{inc} - L_{hrz} - L_{shd} - L_{slg} - L_{iam} + H_{frt} \tag{1}$$

where

Symbol	Meaning	Unit
$H_{eff}$	the effective irradiation on the collectors	kWh/m²
$H_{inc}$	the plane irradiation after the low-light threshold	kWh/m²
$L_{hrz}$	the Far Shadings: Horizon row as a positive loss	kWh/m²
$L_{shd}$	the Near Shadings: irradiance loss row as a positive loss	kWh/m²
$L_{slg}$	the Soiling loss factor row as a positive loss	kWh/m²
$L_{iam}$	the IAM factor on global row as a positive loss	kWh/m²
$H_{frt}$	the Ground reflection on front side row	kWh/m²

Reading the number

A total, positive. A common range is 88 to 95 % of the plane irradiation on a utility plant with rows and 93 to 97 % on a rooftop array without rows in front of it. Row shading, soiling and a high skyline lower it.

API

loss.glob_eff

Symbols follow the symbol registry.