Is home battery discharge intentionally excluded from phase-switch surplus calculation?

[DannNuyd]

I'm running a Solar (PV) mode loadpoint with a SolarEdge battery configured. When the battery is actively discharging to support EV charging, the charge current calculation correctly includes the battery's contribution — but the separate available power value used for the automatic 1p/3p phase-switch decision does not appear to include it. This causes the loadpoint to scale down from 3p to 1p even while the battery is discharging several kW to keep the actual charging session running at full 3-phase power with near-zero grid import.

Setup
evcc version: 2026.8.8
Charger: Alfen Eve Single Pro (Modbus TCP), phases: 0 (auto 1p/3p)
Grid meter: Home Assistant integration (P1/DSMR-based, template sensor combining import/export)
PV + Battery: SolarEdge inverter/battery via Modbus
Loadpoint mode: Solar (pv)

Behaviour: custom
Enable grid power: 0 W
Disable grid power: 4140 W (= 6A × 3 phases × 230V, our calculated 3p minimum)
Disable delay: 3 minutes
Battery settings: prioritySoc ≈ 25%, bufferSoc/bufferStartSoc ≈ 30% (battery was at 60-66% SoC throughout the session below — well above both thresholds)
site residualPower: 200W

Expected behavior
Since the battery was well above its priority/buffer thresholds and actively discharging multiple kW specifically to support the EV charging session, I'd expect that discharge to count toward "available power" for the phase-switch decision — the same way it already counts toward the actual charge current calculation.

Actual behavior
available power tracks something closer to (PV production − base household load), and appears to exclude battery discharge, even while the same debug cycle shows the battery contributing thousands of watts to the actual charging current calculation seconds later/earlier in the same log lines.

[lp-1 ] DEBUG 2026/08/23 10:56:33 detected active phases: 3p
[lp-1 ] DEBUG 2026/08/23 10:57:47 set charge mode: pv
[lp-1 ] DEBUG 2026/08/23 10:57:48 detected active phases: 3p
[site ] DEBUG 2026/08/23 10:57:48 battery 1 power: 3487W
[site ] DEBUG 2026/08/23 10:57:48 pv 1 power: 1093W
[site ] DEBUG 2026/08/23 10:57:48 site power: 3725W
[lp-1 ] DEBUG 2026/08/23 10:57:49 available power 334W < 4140W min 3p threshold
[lp-1 ] DEBUG 2026/08/23 10:57:49 start phase scale1p timer
[lp-1 ] DEBUG 2026/08/23 10:57:49 phase scale1p in 3m0s
[lp-1 ] DEBUG 2026/08/23 10:57:49 pv charge current: min 6A > 2.58A (3725W @ 3p, battery: true)
[lp-1 ] DEBUG 2026/08/23 10:57:49 set charge current limit: 6A

[site ] DEBUG 2026/08/23 10:58:33 battery 1 power: 3456W
[site ] DEBUG 2026/08/23 10:58:33 pv 1 power: 1148W
[site ] DEBUG 2026/08/23 10:58:33 site power: 3663W
[lp-1 ] DEBUG 2026/08/23 10:58:33 available power 357W < 4140W min 3p threshold
[lp-1 ] DEBUG 2026/08/23 10:58:33 phase scale1p in 2m15s
[lp-1 ] DEBUG 2026/08/23 10:58:33 pv charge current: min 6A > 0.691A (3663W @ 3p, battery: true)

[site ] DEBUG 2026/08/23 10:59:33 battery 1 power: 1590W
[site ] DEBUG 2026/08/23 10:59:33 pv 1 power: 3470W
[site ] DEBUG 2026/08/23 10:59:34 available power 2688W < 4140W min 3p threshold
[lp-1 ] DEBUG 2026/08/23 10:59:34 phase scale1p in 1m15s
[lp-1 ] DEBUG 2026/08/23 10:59:34 pv charge current: min 6A > 4.05A (1348W @ 3p, battery: true)

[site ] DEBUG 2026/08/23 11:00:32 battery 1 power: 3198W
[site ] DEBUG 2026/08/23 11:00:33 pv 1 power: 1405W
[lp-1 ] DEBUG 2026/08/23 11:00:33 available power 576W < 4140W min 3p threshold
[lp-1 ] DEBUG 2026/08/23 11:00:33 phase scale1p in 15s
[lp-1 ] DEBUG 2026/08/23 11:00:33 pv charge current: min 6A > 1.04A (3424W @ 3p, battery: true)

[site ] DEBUG 2026/08/23 11:01:02 battery 1 power: 3298W
[site ] DEBUG 2026/08/23 11:01:02 pv 1 power: 1469W
[lp-1 ] DEBUG 2026/08/23 11:01:04 available power 309W < 4140W min 3p threshold
[lp-1 ] DEBUG 2026/08/23 11:01:04 phase scale1p in 0s
[lp-1 ] DEBUG 2026/08/23 11:01:04 switched phases: 1p

Note in every single cycle: battery 1 power is 1500–3500W (discharging, supporting the car), yet available power stays in the 300–600W range and drives the countdown to switched phases: 1p regardless. Meanwhile the very same cycle's pv charge current line clearly does factor the battery in (battery: true, computing a current that sustains 3p at 6A).

Is this intended behavior (i.e. is the battery deliberately excluded from the 1p/3p threshold check, perhaps to avoid using the battery to justify a higher load tier), or is this a bug where available power for the phase-switch decision should be using the same battery-inclusive calculation as the charge current logic?
If intended: is there a way to configure the phase-switch decision to also consider battery discharge (similar to how prioritySoc/bufferSoc already govern whether the battery may support charging at all)?

Happy to provide the full debug log or additional context if useful.

Best regards.
Danny

[mfuchs1984]

At least at the moment, battery supported charging means to charge with minimum power. The battery boost mode provides a way to charge as fast as the battery allows.