A developer detailed a local-only integration of the Marstek Venus E 2.0 battery with Home Assistant. The project used a standard TV mount for installation and a Waveshare RS485 to Ethernet converter to bypass the manufacturer's cloud. The goal was achieving zero export automation and full local control via Modbus TCP.

The author installed a 30kWp PV system in 2020, seeking to boost self-consumption from 50% to 78%. The €1,050 battery promised a six-year ROI. Avoiding the vendor's cloud was key for privacy, control, and robustness, ensuring system operation without internet or vendor support.

The setup uses a Raspberry Pi to read grid meters via MQTT. Home Assistant processes this data and sends Modbus commands to the battery. This creates a closed loop for charging/discharging based on real-time grid import/export, maximizing solar self-consumption locally.