Solax Inverter automation

Author: Pavel Mikula

A Spring Boot application (Java 17+) running on a Raspberry Pi 4B, designed to dynamically control a Solax X3‑Hybrid‑G4 inverter via Modbus TCP. By leveraging real‑time weather data and energy pricing, this tool maximizes self‑consumption and cost savings for private installations.

Note: This application is intended for private use and may require adjustments to suit different environments. It is provided "as-is" without warranty.

🚀 Features

• Dynamic Inverter Control through GPIO pins and Modbus TCP
• Weather‑Aware Operation using Meteosource API forecasts
• Price‑Driven Scheduling via spotovaelektrina.cz (scraped from OTE)
• Daily Rotating Logs with automatic compression

🧰 Prerequisites

Hardware

• Raspberry Pi 4B (Raspbian or compatible)
• Solax X3‑Hybrid‑G4 inverter with Modbus TCP enabled
• If no Modbus TCP on inverter: RS485 → Ethernet converter (e.g., Waveshare industrial server)

APIs

1. Meteosource: Request an API key at https://www.meteosource.com/
2. spotovaelektrina.cz: Ensure access

Software

• Java 17 or higher
• Maven 3.x
• Network access between RPi and Solax inverter

🛠 Installation & Setup

1. Clone the repository

   git clone https://github.com/Firestone82/SolaxAutomation.git
   cd SolaxAutomation

2. Configuration file

   cp src/main/resources/application.yml.example application.yml

   Edit application.yml (see Configuration below).
3. Build

   mvn clean package

4. Run

   java -jar target/solax-automation-*.jar

5. (Optional) Install as Service Create a systemd unit /etc/systemd/system/solax-automation.service:

   [Unit]
   Description=Solax Automation
   After=network.target
   
   [Service]
   User=pi
   ExecStart=/usr/bin/java -jar /home/pi/SolaxAutomation/target/solax-automation-*.jar
   WorkingDirectory=/home/pi/SolaxAutomation
   Restart=on-failure
   
   [Install]
   WantedBy=multi-user.target

   sudo systemctl daemon-reload
   sudo systemctl enable solax-automation
   sudo systemctl start solax-automation

⚙️ Configuration

Edit application.yml or set corresponding environment variables.

solax:
  modbus:
    # Modbus TCP connection
    host: 192.168.0.31
    port: 502
    # Time management required for modbus
    time:
      # Delay between two requests
      delay: 1000
  # ID of the inverter in modbus, can differ if you have multiple inverters
  unitId: 1
   # Advanced password for the inverter
  password: 2014

# API for electricity prices provided to grid
# - Documentation: https://spotovaelektrina.cz/api
ote:
  api:
    url: "https://spotovaelektrina.cz/api/"

# API for weather data
# - Documentation: https://www.meteosource.com/documentation
meteosource:
  api:
    url: "https://www.meteosource.com/api/"
    key: "YOUR_API_KEY"
   # Location for weather data. Lat and lon is always better. How to find is described in the documentation
  location:
     placeId: "prague"
     # Coordinates for the location
     lat: 50.0755
     lon: 14.4378

# Logging configuration
logging:
  config: classpath:log4j2.xml

📜 Logs

Logs are provided to console as well as to the files stored in the logs directory. The log files are rotated daily and compressed to save space.

License & Disclaimer

This project is provided "as-is" for personal use. No warranty is offered. Adapt for your needs, but please do not redistribute without permission.