# tbnobody/OpenDTU

Software for ESP32 to talk to Hoymiles/TSUN/Solenso Inverters

Repository: https://github.com/tbnobody/OpenDTU
Canonical: https://ross.abutalabs.com/products/opendtu
Language: C++
License: GPL-2.0
License Family: copyleft
Topics: esp32, platformio, balkonkraftwerk, mqtt, solar, hoymiles, tsun, solenso
Last push: 2026-08-24T20:41:20+00:00

## Health v2 (maintenance only)
Score: 92/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 77, longevity 100
- inputs: {"age_days": 1531, "days_push": 9, "days_rel": 156, "gap_med": 2.5, "n_releases_24m": 21}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2176, forks 618 (observed 2026-08-28T04:06:22.173530+00:00)

## What it is
OpenDTU is ESP32 firmware that replaces the proprietary Hoymiles DTU cloud gateway for solar micro-inverters, communicating directly over the Hoymiles/TSUN/Solenso radio protocol. It exposes a web interface plus MQTT and Prometheus endpoints for monitoring and controlling the inverter locally.

## Use cases
- monitor my Hoymiles solar inverter without the cloud
- replace the Hoymiles DTU telemetry gateway with open source firmware
- integrate my balcony solar setup with Home Assistant via MQTT
- read live solar production data locally from TSUN inverter
- limit the power output of my micro-inverter
- export solar inverter metrics to Prometheus

## When to choose
- you have a Hoymiles, TSUN, or Solenso micro-inverter and want local, cloud-free monitoring and control
- you want MQTT or Prometheus integration for home automation dashboards
- you want to set inverter power limits from your own network

## When to avoid
- your inverter brand is not Hoymiles/TSUN/Solenso compatible
- you need a ready-made commercial product rather than firmware you flash yourself
- you rely on the vendor cloud portal features

## Facets
- artifact type: application
- maturity: active
- function: iot, monitoring, reverse-engineering, http-server
- domain: iot, energy, self-hosted, hardware
- platform: iot, embedded, self-hosted
- tags: solar, hoymiles, mqtt, dtu, balkonkraftwerk, inverter, platformio, prometheus

## Member repositories
- tbnobody/OpenDTU (main) score 92

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:22.173530+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:48:53.462307+00:00, confidence not recorded.
  - readme: https://github.com/tbnobody/OpenDTU (fetched 2026-08-28T04:06:22.173530+00:00, sha 06ef886b082c)
- Data as of 2026-08-30T08:39:29.467469+00:00.