Battery
A battery represents a home storage system. Power Insight tracks charge and discharge power, which sources charged the battery (grid vs. solar), and the levelized cost of storage. If you have multiple batteries, add one device each.
Add it with Add device → Battery.
Fields
Name
A unique name for this device, for example "Home Battery". Used as the device name in Home Assistant.
Power entity
Sensor that reports this device's power in W, kW or MW.
Sign convention: battery — positive = discharging, negative = charging. Use Invert power direction if your sensor uses the opposite sign.
Invert power direction
Turn on if your sensor reports power with the opposite sign to the expected convention.
Round-trip efficiency
Round-trip efficiency in percent — the share of energy stored that you actually get back when discharging (typical values: 85–95 %). Used to correctly attribute charging losses to their source.
Default: 95.
Exports power to grid
Turn on if this device can feed surplus power back to the grid. Enables export-compensation tracking when the corresponding option is active.
Default: off for batteries.
Export compensation rate
The amount you are paid per kWh of power exported to the grid, in your currency. Required when export-compensation or savings sensors are enabled.
Default: 0.0.
Charges from
Select which sources this battery can charge from — the grid and/or specific PV systems you have configured. Power Insight uses this to trace how much of the battery's stored energy came from each source.
This drives the battery's blended charging cost and its charging-source-share sensors. Batteries are never selectable as a charge source for another battery.
When you add or remove a grid or PV device, Power Insight raises a repair issue asking you to reconfigure each battery so its charge-source list stays correct.
Lifetime production / Total lifetime cost / CO₂ footprint
These behave exactly as for a PV system. Together, lifetime cost ÷ lifetime throughput gives this battery's LCOS. Changing them later applies a correction factor.
CO₂ footprint has no effect yet — CO₂ sensors are not implemented.
Sensors this device can create
The battery has the same sensor set as a PV system, plus:
| Sensor | Unit | Enabled by |
|---|---|---|
| Charging source shares (one per configured source) | % | Charging source shares (%) |
These show how much of the battery's current charging power comes from each source — for example "currently 70 % from solar, 30 % from the grid". Only sources you selected in Charges from appear.
See the Entity reference for the full list.
Batteries always cost money to charge, so their savings go negative while charging and positive while discharging. This is expected — see the FAQ.