Energy at POI after storage

What this step does

The row closes the storage block: the energy injected into the grid with the battery, after its charge and discharge and the grid power limitation. With AC coupling the injection is the solar injection less the power taken to charge, plus the power the battery delivers. With DC coupling it is what the AC losses leave of the inverter output with the battery.

The math

1. The closing total

$$E_{after} = \frac{1}{P_{DC}} \sum_i \min\!\big(p'_i,\ \max(P_{POI},\ p_i)\big)\,\Delta t \tag{1}$$

where

Symbol	Meaning	Unit
$E_{after}$	the running total after this row	kWh/kWp
$P_{DC}$	the system DC nameplate	kWp
$p'_i$	the system's grid injection with the battery at timestep $i$	kW
$P_{POI}$	the system's grid power limitation, unbounded without one	kW
$p_i$	the system's grid injection before the battery at timestep $i$	kW
$\Delta t$	the length of one timestep	h

Reading the number

A total, positive. With AC coupling it sits below the solar total by the conversion losses, the change in stored energy and any curtailment at the POI limit. With DC coupling it exceeds the solar total when the battery recovers more clipping than its conversion losses.

API

storage.poi

Symbols follow the symbol registry.