Solar-plus-storage coupling: AC, standard DC and reverse DC
AC-coupled
Two inverters.
Merge on the AC bus.
AC bus
Solar PV
Inverter
Battery
Inverter
Grid
Standard DC-coupled
One shared inverter.
Merge on a DC bus before it.
Round trip efficiency: ~2% above AC
DC bus
Solar PV
Battery
DC-DC
converter
Solar/hybrid
inverter
Grid
Reverse DC-coupled
One shared inverter.
Battery sets the DC bus.
Round trip efficiency: ~2.5% above AC
DC bus
Solar PV
DC-DC
converter
Battery
Battery
inverter
Grid
Round-trip efficiency is for solar charging; AC leads on grid charging. Hover any component for detail.
MODOENERGY