Green Button Energy Import
If you’re an Avangrid utility customer (RG&E, NYSEG, Central Maine Power, United Illuminating, Connecticut Natural Gas, Southern Connecticut Gas, or Berkshire Gas) and you’ve ever wanted your full historical usage data in the Energy Dashboard — this integration is for you.
Avangrid provides a “Green Button” data export from their utility websites. This integration lets you take those CSV or XML files and import them directly into HA’s long-term statistics database, with correct historical timestamps, via a simple drag-and-drop sidebar panel.
What It Does
- Drag-and-drop import panel — a sidebar panel appears in HA after setup. Drop your downloaded CSV or XML file onto it, and the data is imported immediately.
- Full historical backfill — imports months or years of hourly kWh/therm data with the correct past timestamps so the Energy Dashboard’s history charts are fully populated.
- Monthly billing import — import your monthly billing CSVs to populate the Energy Dashboard’s cost view with your actual billed amounts instead of a static price estimate.
- Safe re-imports — duplicate rows are automatically skipped. You can re-drop the same file without creating duplicates.
- CSV and XML support — works with Avangrid’s Opower CSV export and standard Green Button ESPI XML exports.
- No YAML required — set it up entirely through the UI under Settings → Devices & Services.
Screenshots
Supported Utilities
| Utility | State | Service |
|---|---|---|
| Rochester Gas & Electric (RG&E) | New York | Electric & Gas |
| New York State Electric & Gas (NYSEG) | New York | Electric & Gas |
| Central Maine Power (CMP) | Maine | Electric |
| United Illuminating (UI) | Connecticut | Electric |
| Connecticut Natural Gas (CNG) | Connecticut | Gas |
| Southern Connecticut Gas (SCG) | Connecticut | Gas |
| Berkshire Gas | Massachusetts | Gas |
How It Works
Avangrid’s website lets you download your smart meter data as a CSV or XML file. This integration reads that file and uses HA’s async_import_statistics API to write hourly readings directly into the recorder’s long-term statistics database — the same place your live energy sensors write to — but with the historical timestamps from your file.
The result: the Energy Dashboard sees months of backfilled hourly data as if HA had been running since your meter was installed.
The sidebar panel is a browser-native Web Component that reads your file via FileReader, sends the content over the existing HA WebSocket connection, and displays import results inline. No filesystem access is needed on the client side.
Installation
Via HACS (recommended):
- HACS → Integrations → ⋮ → Custom repositories
- Add
https://github.com/cskolny/ha-green-button-energy, category: Integration - Download and restart HA
- Settings → Devices & Services → Add Integration → Green Button Energy Import
Manual:
Copy the custom_components/green_button_energy/ folder into your HA config directory and restart.
Tested On
- Home Assistant 2026.3.x
- Integration v1.7.0
Feedback Welcome
This is a work in progress and I’d love to hear from others in the community:
- Does it work with your Avangrid utility?
- Are there edge cases in the CSV or XML format I haven’t handled?
- What features would be most useful to add next?
Open an issue on GitHub or reply here — any and all feedback is appreciated! 
This project is not affiliated with or endorsed by Avangrid or any of its subsidiaries. Avangrid, RG&E, NYSEG, and other utility names are trademarks of their respective owners.