Energy Meter Tracker — Half-hourly electricity metering app for Home Assistant
I’ve built a Home Assistant app that records your electricity usage in precise half-hour blocks — the same intervals UK energy supplier uses for billing.
Why?
The built-in Energy dashboard tracks totals but doesn’t give you visibility into individual half-hour periods. If you’re on an Agile or time-of-use tariff, or you want to understand how your battery, EV charger or heat pump is affecting your grid consumption, you need half-hourly data.
What it does
- Records import and export meter readings at every :00 and :30 boundary
- Boundary interpolation — even if your sensor updates every 60 seconds, the block delta is calculated precisely to the boundary timestamp, not to whenever the last reading happened to land
- Sub-meter support — track EV chargers, home batteries and heat pumps; the engine distributes grid consumption across them using a grid-authoritative algorithm (the main meter is always the source of truth)
- Gap filling — if the app restarts mid-session it detects missing blocks and interpolates them automatically
- Backup — data is copied to
/shareafter every block finalise, with zip snapshots before every config change - Four HA sensors — cumulative import/export kWh and cost, compatible with the Energy dashboard and Utility Meter
- Web UI — config wizard, charts, logs viewer, help page, all accessible from the sidebar
Requirements
- Smart meter with a CAD (Consumer Access Device) publishing readings via MQTT to HA at regular intervals (10 second updates recommended) - (I’m using a Hildebrand headless CAD with sensors created by GitHub - megakid/ha_hildebrand_glow_ihd_mqtt: Home Assistant integration for local MQTT Hildebrand Glow IHD · GitHub)
- Cumulative kWh sensors for import and export
- Live £/kWh rate sensors (works great with the Octopus Energy integration)
- Home Assistant OS or Supervised
Installation
Add the repository to your HA app store:
https://github.com/RGx01/energy-meter-tracker-addon
Settings → Apps → App Store → ⋮ → Repositories → paste the URL above.
Disclaimer
This app is for informational use only. It provides a close approximation of your half-hourly consumption based on local sensor readings. It cannot replicate your supplier’s authoritative HH reconciliation — do not use it for billing disputes.
Feedback welcome
This is a v1.1.0 release — feedback, bug reports and feature requests are very welcome via GitHub Issues. I’m particularly interested in hearing from users with tariff types and set ups.
