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Upgrading from v2

RGx01 edited this page Jun 26, 2026 · 1 revision

Upgrading from v2

3.0 is a drop-in upgrade. Nothing you have changes, and nothing new is forced on you. Everything 3.0 adds — supplier settlement, Intelligent Octopus Go pricing, the Octopus Home Mini source — is opt-in. If you do nothing but update, EMT keeps recording and billing exactly as it did in 2.x.


What happens automatically

On first start after upgrading What EMT does
Your data Blocks, configuration, billing periods and history are all preserved.
Database schema Migrations run automatically — no action needed.
Carbon backfill 🇬🇧 UK postcode installs get a one-time background pass that fills gCO₂/kWh for your existing 2.x blocks. It self-heals if interrupted by a restart. See Carbon Intensity.

ℹ️ The upgrade is additive. There is no destructive migration step and no re-import to run.


What stays the same

  • Your data-source mode defaults to cad (local metering only) — precisely how 2.x worked. Your recording and billing are unchanged.
  • All your sensors, billing periods and tariff history carry over untouched.
  • You do not need an Octopus account, an API key, or any new configuration to keep using EMT as before.

What's renamed

A couple of things are called something new in the UI. No data or settings change — only the labels:

2.x 3.0
Sub-meters Devices (your EV charger, battery, heat pump)
Live Power page Overview page (now also works without a live-power sensor)

What's new — and entirely opt-in

When you're ready, open the Setup Wizard (or Change Setup) to switch any of these on:

  • Supplier Settlement — reconcile blocks against the settled half-hourly data Octopus bills from.
  • Intelligent Octopus Go — price smart-charge dispatch slots at the off-peak rate.
  • Octopus Home Mini as a live-power source — see Overview.
  • Carbon Insights and gCO₂/kWh charts — available on UK postcode installs (see Insights and Charts).

⚠️ Changing your data-source mode later (via Change Setup) can trigger a full recalculation, so it's behind a confirmation step. See Managing Billing Periods.


If you already used the Octopus API

If you configured Octopus API access in an earlier build — before the supplier field existed — EMT infers Octopus from your stored credentials. You don't need to re-enter anything.


Restoring an older backup

A v2-era backup that has no supplier field restores cleanly as local-metering-only (cad). It won't half-enable any API features. After a restore, the published Home Assistant sensors reflect the cumulative total as of the last block in the restored database — see Home Assistant Sensors.


After upgrading — a quick check

  1. Open Overview (formerly Live Power) — confirm your gauges and cards look right.
  2. Glance at Charts → Billing for the current period — totals should match what you saw on 2.x.
  3. If you're on a UK postcode, the carbon backfill runs quietly in the background; Carbon Insights will fill in as it completes.
  4. Nothing else is required. Switch on the new supplier features whenever you choose.

ℹ️ If anything looks off, your previous data is untouched — review backups under Data Management.


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