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Send solar, grid and battery data from Home Assistant

Share your solar, grid and battery readings from Home Assistant with Cala, and check that your Cala is receiving them.

Updated November 2, 2026

Once your Cala is paired with Home Assistant, it can see what your solar panels are producing, whether you're importing or exporting power, and how full your home battery is. Cala uses these readings to plan its heating. Home Assistant only shares information: your Cala stays in control of how it heats.

Set up your Energy dashboard

There's nothing to set up in the Cala integration. Cala reads the same power sensors that Home Assistant's Energy dashboard uses. If your Energy dashboard already shows your solar, grid and battery power, you're done: skip to Check that your Cala is receiving the readings.

  1. In Home Assistant, go to Settings → Dashboards → Energy.

  2. Under Solar panels, add your solar production power sensor.

    Home Assistant Energy settings: the Electricity grid section with Add grid connection, and Solar panels with one solar production sensor (serial number blurred)
    Add your solar production under Solar panels.
  3. Under Electricity grid, add your grid power sensor.

  4. Under Home battery storage, add your battery power sensor and its state of charge.

    Home Assistant Energy settings: Solar panels, Home battery storage with Add battery system, and Individual electrical devices
    Add your battery under Home battery storage.
  5. Save. The Cala integration reloads by itself and starts sending these readings to your Cala.

Tell Cala when your home is off the grid

If you have a battery or other backup power, Cala can also know when your home has lost utility power. The Energy dashboard has no power-outage sensor, so you choose it in the Cala settings. This is optional.

  1. In Home Assistant, go to Settings → Devices & services → Cala and click Configure.

  2. Choose Settings (TOU price feed, publish interval), then click Submit. The Settings page opens.

  3. In Grid status entity (on-grid / off-grid), choose the sensor that tells you whether your home is on utility power, such as your battery system's grid status.

  4. If your sensor is on during an outage instead of while the grid is connected, turn on Invert grid status (entity is on during an outage).

  5. Click Submit. The integration reloads with your change.

Other settings

The same Settings page has two more options. Most homes can leave them as they are.

  • Solar/grid/battery publish interval: how often, in seconds, the readings are sent to your Cala even when nothing has changed. The default is 30 seconds. Changes are also sent as they happen.

  • Choose solar, grid and battery sensors by hand: for systems the Energy dashboard can't describe. Turn it on and click Submit to open a page where you pick each sensor yourself, and say which direction is positive for your grid and battery power. These choices replace the ones from the Energy dashboard. Leave it off to follow the Energy dashboard.

Check that your Cala is receiving the readings

  1. On your Cala's screen, from the Home screen, press Up or Down until SETTINGS is highlighted, then press Select.

  2. Press Down until DEVICE STATUS is highlighted, then press Select. The STATUS screen opens.

  3. Press Select to open DETAILED STATUS.

  4. Press Down until you reach SOLAR & BATTERY.

    DETAILED STATUS scrolled to SOLAR & BATTERY: Source home_assistant, Last Reading just now, Solar Now 2140 W, Battery 78% chg, Grid export 860 W
    SOLAR & BATTERY when Home Assistant readings are arriving.

When everything is working, you see:

  • Source: home_assistant
  • Last Reading: "just now" or a few minutes ago
  • Solar Now: what your panels are producing, in watts
  • Battery: your battery's charge, followed by "chg" while it's charging or "dis" while it's discharging
  • Grid: "import" or "export" and the power in watts, or "idle"

A row that reads "n/a" means that reading isn't being sent, usually because it isn't on your Energy dashboard. If Last Reading: says "never", check that your Cala's HOME ASSISTANT screen shows Status: Connected.

Press Back to leave the status screens.

In the Cala app

In the Cala app, tap the menu icon at the top left, tap SYSTEM INTEGRATIONS, then tap Solar & Battery. When readings are arriving, the screen shows Home Assistant with CONNECTED, what Cala can see (solar only, or solar and battery), and under "Right now" your solar power in KW SOLAR and your battery's charge. See Set up Solar & Battery.

SOLAR & BATTERY screen with Home Assistant CONNECTED, the Right now card with 4.1 KW SOLAR and 82% battery
When readings are arriving, Solar & Battery shows Home Assistant as CONNECTED.

To choose how Cala uses your exported power and your battery, see Fine-tune how Cala heats: Advanced Settings.