Marstek Venus Energy Manager

Abstract

1. Introduction

The Marstek Venus Energy Manager is a comprehensive Home Assistant integration designed to monitor and control Marstek Venus E and C series batteries (v2 and v3) and Venus D and Venus A series batteries via Modbus TCP. It provides advanced energy management features including predictive grid charging, customizable time slots for discharge control, and device load exclusion logic.

2. Objective

Custom integration to monitor and control Marstek Venus E v2, Venus E v3, Venus A, and Venus D systems in Home Assistant.

This project demonstrates how Python can be applied to a real-world Internet of Things (IoT) problem.

3. Key Features / Modules

• Zero Export/Import PD Controller: Keeps grid exchange near zero using a Proportional-Derivative algorithm.
• Oscillation Prevention: Deadband and derivative gain prevent rapid charge/discharge cycling.
• One-Click PD Profiles + Quality Sensor: Pick a tuning profile (Very smooth → Very aggressive) instead of tuning gains by hand; a control-quality sensor reports whether the result is stable, oscillating or sluggish.
• Multi-Battery Support: Manage up to 6 batteries with intelligent load sharing and SOC-based priority.
• Time Slots (v2): Per-battery windows with independent charge/discharge ticks, optional SOC and power overrides, and a manual mode that forces a fixed charge or discharge power. Up to 8 slots per integration.
• Weekly Full Charge: Forces 100% SOC once a week for LFP cell balancing.
• Solar-Aware Charge Delay: Holds back grid charging while solar can still cover the required energy.
• Peak Shaving: Reserves battery capacity to cover demand spikes above a configurable power threshold, keeping energy in reserve rather than covering all consumption.
• Load Exclusion: Mask high-power devices (e.g. EV chargers) so the battery doesn't try to cover them.

4. Technology Stack

5. System Requirements

General requirements for this technology stack — check the README for exact versions.

• Python 3.8 or later
• pip / virtualenv for dependencies
• VS Code, PyCharm or Jupyter Notebook
• Git (to clone the repository)

6. Installation & Setup

git clone https://github.com/ffunes/Marstek-Venus-Energy-Manager.git
cd Marstek-Venus-Energy-Manager

Full setup instructions are in the project README.

7. Future Enhancements

Suggested extensions you can add to make this your own project.

• Add a mobile dashboard using Blynk or Firebase
• Store readings in a cloud database for history charts
• Add alerts via SMS / Telegram when thresholds are crossed

8. Viva / Review Questions

Common questions examiners ask for projects in this domain.

1. Which microcontroller / board and sensors are used and why?
2. How does the device send data (Wi-Fi, MQTT, HTTP, Bluetooth)?
3. Where is the sensor data stored and visualised?
4. How is power consumption managed?
5. How would you secure the device and its communication?

9. Source Code & License

This project is developed by ffunes and published on GitHub under the GNU General Public License v3.0. Please follow the license terms and credit the original author when you use or modify this code.