Home Assistant Solar Automation — The Complete Setup Guide

Having solar panels without automating them in Home Assistant is like having a sports car and only driving in first gear. The panels produce power whether you use it or not — the question is whether that power goes into your home loads, your battery, or out to the grid for little or no benefit.

This guide is based on a real 10kW SolaX X1-Hybrid-G4 installation in Pretoria with a 10.2 kWh battery, running Home Assistant with 869 entities. The automations below are tested and running daily.

Step 1 — Get Your Inverter into HA

Before you can automate anything, HA needs to see your inverter's data. The integration depends on your inverter brand:

• SolaX: Install the SolaX integration via HACS. Gives you 50+ sensors including battery SOC, charge rate, PV power per string, grid import/export, and inverter mode.
• Deye / Solarman: Use the Solarman integration from HACS. Similar sensor set.
• Victron: VenusOS MQTT integration. Exceptional data quality.
• Growatt: Growatt integration via HACS. Uses cloud polling — slight delay.
• Generic / unknown: Install a Shelly EM clamp meter on your DB board. Gives grid import/export and consumption via WiFi, no cloud dependency.

Verify your integration is working by checking Developer Tools → States and searching for your inverter sensors. You should see battery SOC, PV power, and grid power updating in real time.

Step 2 — The Geyser Automation (Start Here)

An electric geyser is the single best target for solar automation. It's a pure resistive load (2–3kW), it doesn't care when it runs, and hot water stores the solar energy for hours. Here is the automation that runs on the real system:

automation:
  - alias: "Geyser on during solar excess"
    description: "Turn geyser on when battery charging strongly"
    trigger:
      - platform: numeric_state
        entity_id: sensor.solax_battery_1_power_charge
        above: 1000
        for: "00:05:00"
    condition:
      - condition: time
        after: "09:00:00"
        before: "15:30:00"
      - condition: numeric_state
        entity_id: sensor.solax_battery_soc
        above: 40
    action:
      - service: switch.turn_on
        entity_id: switch.geyser
        
  - alias: "Geyser off when solar drops"
    trigger:
      - platform: numeric_state
        entity_id: sensor.solax_battery_1_power_charge
        below: 200
        for: "00:03:00"
      - platform: numeric_state
        entity_id: sensor.solax_battery_soc
        below: 30
    action:
      - service: switch.turn_off
        entity_id: switch.geyser

The 5-minute delay on the trigger prevents the geyser from toggling on and off during brief cloud cover. The SOC condition ensures you don't drain the battery below a useful level just to heat water.

Step 3 — AC Tiered Solar Mode

Air conditioning is your biggest variable load and the most powerful tool for solar self-consumption. The approach that works best is a tiered system with three modes that shift automatically based on available power:

• Boost mode (22°C, fan high): PV > 3kW AND battery > 70% SOC
• Normal mode (24°C): PV > 1.5kW
• Eco mode (26°C): Battery 30–50% SOC
• Off: Battery < 30% OR grid only after 21:00

This runs through a HA choose action in a single automation, triggered every time the battery SOC or PV power changes significantly. The real-world effect is that during a good solar day, the house sits at 22–23°C for free. On a cloudy day it conserves battery for the evening.

Step 4 — Pool Pump and Other Deferrable Loads

Pool pumps are ideal solar loads — they need to run every day, the exact timing doesn't matter, and they're simple on/off devices. Schedule them to run during peak solar hours (10:00–16:00) with a battery SOC condition:

automation:
  - alias: "Pool pump solar window"
    trigger:
      - platform: time
        at: "10:00:00"
    condition:
      - condition: numeric_state
        entity_id: sensor.solax_battery_soc
        above: 50
    action:
      - service: switch.turn_on
        entity_id: switch.pool_pump
        
  - alias: "Pool pump off at 16:00"
    trigger:
      - platform: time
        at: "16:00:00"
    action:
      - service: switch.turn_off
        entity_id: switch.pool_pump

Step 5 — Daily Solar Summary Notification

A sunset notification that summarises the day's production keeps you connected to your system without having to open the dashboard every day. This is one of the most satisfying automations to have running:

automation:
  - alias: "Daily solar summary"
    trigger:
      - platform: sun
        event: sunset
    action:
      - service: notify.mobile_app_your_phone
        data:
          title: "☀️ Solar Summary"
          message: >
            Today: {{ states('sensor.solax_today_s_solar_energy') }} kWh produced.
            Grid import: {{ states('sensor.solax_today_s_import_energy') }} kWh.
            Battery: {{ states('sensor.solax_battery_soc') }}% charged.

Things to Watch Out For

• Inverter unavailability: Add a condition checking your inverter integration is available before triggering load control. If the integration goes offline, you don't want automations running blind.
• Sequential command delays: When sending multiple commands (e.g., change AC mode then temperature), add a 2-second delay between them. Some climate entities don't process simultaneous commands correctly.
• Battery cutoff: Always protect a minimum SOC for overnight use. 28–30% SOC is a sensible hard floor for a 10 kWh battery — that's about 2.5–3 kWh of usable reserve.
• Grid outage detection: The sensor.solax_inverter_mode entity changes value during a grid outage. Build a separate automation for outage mode that shuts down high-drain loads and sends a notification.