Module mismatch: power loss at MPP

What it is

The power lost because the modules in a string do not all have the same current-voltage curve, so the string cannot operate every module at its own maximum. The input is a fraction of the array power.

Typical values and how to get it

2 % is a common design value. If not given: 0: no module mismatch.

How it is applied

$$P_{\text{after}} = P_{\text{before}}\,(1 - f_{\text{mism}})$$

where

Symbol	Meaning	Unit
$P_{\text{after}}$	the array DC power after this derate	W
$P_{\text{before}}$	the array DC power before it	W
$f_{\text{mism}}$	this input as a fraction	—

API

dc_losses.module_mismatch_loss — sent as a fraction 0–1

Symbols follow the symbol registry.