Savings
Solar the house cannot use at noon can charge the battery and come back out in the evening. The saving is the retail energy you no longer buy, minus whatever export would have paid. It is not a fixed percentage of the bill.
A residential energy storage system holds electricity from the roof and releases it later. The battery stores direct current. An inverter turns that into the alternating current the house already uses, and it decides whether the panels, the battery, or the grid is supplying the load. A controller sets the charge window, the reserve kept for an outage, and any export limit. The grid is optional: some homes use it every day, and some never connect.
Solar the house cannot use at noon can charge the battery and come back out in the evening. The saving is the retail energy you no longer buy, minus whatever export would have paid. It is not a fixed percentage of the bill.
Outage cover applies to the circuits wired to the backup output. The on-grid nameplate and the backup rating are often different numbers. Whole-home backup needs a backup panel and an inverter specified for that job.
Where export is unpaid, capped, or simply not wanted, storage raises the share of solar used on site. The battery moves kilowatt-hours in time. It does not make the array larger.
A hybrid or all-in-one unit charges from the panels and feeds the house as one design. A grid inverter, a separate charger, and a backup inverter can be combined only when each manual allows it.
Useful settings are concrete: a reserve that stays in the battery, a charge window that matches the tariff, and an export limit the utility requires. An app that cannot set those does not manage the system.
Another battery module helps only if the inverter charge current, the BMS, the cable, and the room can take it. Extra kilowatt-hours do not raise the inverter’s backup watts.
The same house can be drawn three ways. Red is direct current, between the panels, the battery, and the inverter. Amber is alternating current, toward the grid and the loads. Switch the layout to see which paths stay live.
Panels and the battery feed the inverter on direct current. Alternating current leaves only toward the backup load. The utility and the ordinary home load are left out of this layout. When the battery is empty and the array is dark, those backup circuits stop. Size the pack and the inverter for the load you actually need at night.
Panels and the battery stay on the DC side. The inverter can also take power from the utility, or feed it, and it supplies the home load. Backup circuits are the ones that can stay on if the grid opens. Circuits left on the grid side of the transfer go dark in an outage. Hybrid does not mean every socket in the house is backed up.
The battery and the inverter ship as one cabinet. Direct current still comes in from the panels. Alternating current still goes out to the grid, the home load, and the backup load. The cabinet removes the wiring between a separate battery and a separate inverter. It does not remove the PV input limit, the backup rating, or the battery size.
A plain comparison of the two inverter jobs is in hybrid vs off-grid inverter. How an LFP pack behaves in a house system is in LFP batteries for a house solar system.
Send the evening load, the circuits you want in an outage, and the array size. We will say which parts of that list ShineTong can supply, and which parts stay with the inverter maker.