goodwe-addon/goodwe_controller/DECISIONS/OPT-11-battery-modes.md

OPT-11 - battery modes, per battery

A battery's mode (on/off, Solar first, Leftover solar) is a soft unit limit at P_MODE = 35 that always holds 0 W. A SET above 35 (a safety stop) overrides it; a limit above 35 (the peak guard) makes it give way only as far as that limit needs, and a battery its mode holds back then carries only what the others cannot (arbiter._unit_modes(), _site_mode()). Design and owner answers: goodwe-session/OPT-11-design.md (2026-09-27); P1 is its section 6 P1, and the pull request lists what was measured.

• Off by default (battery_modes_enabled); off, commands are byte-identical to a5dddad (test_modes.py part 1).
• Off is a mode range, so the peak guard can still use an Off battery when the others cannot cover the floor (design sections 2-3). Whether Off should be absolute is an open owner question.
• Review (PR #149): releasing only when the peak floor bound S let a trade won above the floor keep the modes and place less than the floor, and let a capped grid charge release an Off battery. Both are graded in test_arbiter.py part 11. The loop bound leaves a side that reaches the rail to the rail, so SAFETY-03 still flags a loop winding into it.
• P2 (HA entities): a select and a switch per battery, only while modes are on; commands go through handle_action(), the page's path. A retained command is dropped, not applied: the store already holds the last choice, and a replay after a restart could otherwise undo a newer one. The config topics announced are kept in the store (mqtt_mode_configs), so turning modes off removes exactly those, and an install that never turned them on publishes what ed739d4 did (test_mqtt.py part 10). A removed topic stays in that list and its empty config is re-sent on each start, so a start with no broker cannot lose it; re-sending is harmless. The HA options are the page's English names, pinned by a test, and are not renamed with the page: automations send them.
• In P1 only Off closes a direction; Leftover solar differs by charging last.
• P3 (price runs, priceruns.py, modetrade.py): each battery's range is narrowed by its role this tick (hold, give, charge, rest, sell); main.py files the intersection with the switch, so it still holds 0 W. With modes on the site trade is filed by the modes, sized from the loop bound (so no battery a mode or a refusal holds is asked for watts, P1's unmet share) and the guard's headroom; arbitrage.decide() runs only with modes off, which stays byte-identical to 7a00f12 (test_modes_p3.py part 1).
• SAFETY-46 item 2 is decided as the owner answered (2026-09-25): a trade is a run of consecutive firm slots. It applies with battery modes on; the modes-off trade keeps its one-period shape, because that path must not move.
• Choices that were measured, not assumed (tools/opt11p3_replay.py):
  • a sale needs the guard to have measured the quarter, not to be clear: a 5 kW discharge alone reads "engaged" on export and flipped the sale every 5 s;
  • a grid charge makes the others rest, so it starts only at 500 W and, once the guard or the headroom stops it, stays off for that 15-minute period (without: 13 flips in 4 minutes under a 3.5 kW house);
  • stored energy is valued at the last cheap run for 12 h, and a charge needs its own run to clear the spread (without: a night charge was spent on flat morning prices, then charging went on at them);
  • a run edge reseeds the loop at the house's level (a 3 kW import spike removed; about 0.1 x rating still overshoots as export).
• Replay (tools/opt11p3_replay.py, 16 recorded days, EPEX hourly prices a year earlier, modelled batteries), net EUR, lower is better: P2 19.33, P3 Solar first + Leftover solar 19.57, with a sale 19.60, the old one-period trade 18.14. Review of #153 (same model, with a per-action split):
  • the cheapest hours were at midday on 15 of 16 days, so Leftover solar (acting as Cheap hours until P4) bought 12.2 kWh there that the sun would have given: 7 kWh more exported, 12 kWh less solar stored. Holding for the expensive hours saved 4 kWh of import, not enough. With no grid charge on Leftover solar: 19.44;
  • the old trade charged one hour, so the afternoon sun still fit;
  • a sale earned the wholesale price (2.27 EUR for 11.4 kWh) and the house then bought the same energy back (2.29 EUR): a wash before wear. It pays only when the sale hour's wholesale price beats the later import price, levies included (about 0.13 EUR/kWh above that hour's wholesale here);
  • valuing the charge left at the end, wear and real Flemish levies make selling worse and do not change the order.
• Owner decision 2026-09-29 (option A): selling is off until it can be judged on the price the grid pays (packmode.SELLING_ENABLED, code kept), and Leftover solar takes solar only until P4's forecast (packmode.GRID_CHARGE_MODES); Cheap hours only still charges from the grid. Replayed (16 days, as above): Solar first + Leftover solar 19.44 EUR net against P2's 19.33; Solar first + Cheap hours only 19.57.
• Not done in P3: the forecast (P4), and a headroom too short for the run moving the rest to the next cheap periods.