Battery Priority Flag

[psecker]

I added this maybe its useful to others

Battery Priority Flag — Correct Surplus Calculation

Problem: When batteries were charging (e.g. absorbing 2 kW of solar), AURUM was
reporting ~1700W of surplus for devices even though the grid meter showed 0W export.
The old formula treated battery charging power as "redirectable surplus":

excess (old) = -grid_ema_asym - battery_power_net   →   pv - house

This counted battery absorption as available for devices, which was wrong.

Correct behaviour: Surplus for solar devices should be what's actually being
exported to the grid. When batteries absorb all available solar, grid ≈ 0, so
surplus ≈ 0.

Fix: Added battery_priority boolean flag to AURUM config.

New formula when battery_priority: true (current setting):

excess = -grid_ema_asym   →   pv - house - battery_charge

Batteries take priority. Only genuine grid export counts as surplus.

Legacy formula when battery_priority: false:

excess = -grid_ema_asym - battery_power_net   →   pv - house

Battery charging is counted as redirectable surplus (old behaviour).

Files changed:

• custom_components/aurum/const.py — added CONF_BATTERY_PRIORITY = "battery_priority"
• custom_components/aurum/modules/energy.py — updated excess calculation logic
• custom_components/aurum/config_flow.py — added Boolean toggle in Settings UI
• .storage/core.config_entries — set battery_priority: true in AURUM options

Configure via UI: Settings → Integrations → AURUM → Configure → "Battery Priority" toggle.

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[cm-makes]

Great analysis — and you're right that the old formula deliberately treats charging power as redirectable surplus (per-device SOC thresholds were meant as the guard, but that's clunky if you simply want "battery first, always").

Your approach is now built in: v1.11.0 adds a Battery priority toggle in the battery settings (Settings → Integrations → AURUM → Configure → Settings). On = only genuine grid export counts as surplus, exactly your formula. Off (default) keeps the legacy behaviour, so nothing changes for existing installs.

Thanks for prototyping this — the release notes credit you. Feedback welcome once you've switched from your local patch to the built-in flag!