diff --git a/backend/services/planning_engine.py b/backend/services/planning_engine.py
index 6d6f967..40929a3 100644
--- a/backend/services/planning_engine.py
+++ b/backend/services/planning_engine.py
@@ -633,6 +633,20 @@ def _pv_store_value_czk_kwh(slot: PlanningSlot, min_spread: float) -> float:
     return future - min_spread
 
 
+def _horizon_fixed_tariff_like(slots: list[PlanningSlot]) -> bool:
+    """
+    Fixní nákup (KV1): buy v horizontu je prakticky konstantní.
+    U spotu (home-01) nesmí expensive_import používat charge_acquisition — jinak
+    buy > ~1 Kč označí téměř všechny sloty jako drahé (gi=0 pro dům) → Infeasible.
+    """
+    buys = [float(s.buy_price) for s in slots if float(s.buy_price) >= 0.0]
+    if not buys:
+        return False
+    if len(buys) == 1:
+        return True
+    return max(buys) - min(buys) < 0.25
+
+
 def _pre_negative_sell_export_window(
     slots: list[PlanningSlot],
 ) -> tuple[int | None, int | None]:
@@ -747,10 +761,12 @@ def solve_dispatch(
     operating_mode: str = "AUTO",
     charge_commitment_prev_w: Optional[list[Optional[float]]] = None,
     planner_version: str | None = None,
+    relaxed_expensive_import: bool = False,
 ) -> tuple[list[DispatchResult], int, dict[str, Any]]:
     """
     LP solver pro dispatch optimalizaci.
     Vrátí (výsledky, solver_duration_ms, solver_debug_snapshot).
+    relaxed_expensive_import: nouzový režim po Infeasible — síť smí krmit baseload v drahých slotech.
     """
     T = len(slots)
     if T < 1:
@@ -1364,15 +1380,19 @@ def solve_dispatch(
             ):
                 prob += ge_pv[t] == 0
             # Drahý nákup: dům + TČ z baterie (ne import ze sítě); síť jen EV (+ případně TČ).
-            # Spot: buy > min horizontu. Fixní tarif (KV1): buy > charge_acquisition (jinak je vše „stejně drahé“).
-            expensive_import_slot = buy_t > ref_buy_horizon + min_spread or (
-                buy_t > charge_acquisition_czk_kwh + min_spread
-            )
+            # Spot (home-01): buy > min ne-záporného buy v horizontu.
+            # Fixní tarif (KV1): navíc buy > charge_acquisition (konstantní buy ≈ ref).
+            expensive_import_slot = buy_t > ref_buy_horizon + min_spread
+            if _horizon_fixed_tariff_like(slots):
+                expensive_import_slot = expensive_import_slot or (
+                    buy_t > charge_acquisition_czk_kwh + min_spread
+                )
             if expensive_import_slot and t not in charge_slots:
-                # Síť jen pro EV + skutečný výkon TČ v tomto slotu (hp[t]), ne celý dům.
-                prob += gi[t] <= ev_cap_t + hp[t]
-                if om == "AUTO":
-                    # Bazál + TČ z baterie/FVE; hp[t] může být 0 — nesmí se použít hp_rated (infeasible).
+                # Strict: síť jen EV+TČ; baseload z baterie/FVE. Relaxed: síť smí krmit baseload (nouzový režim).
+                prob += gi[t] <= ev_cap_t + hp[t] + (
+                    float(s.load_baseline_w) if relaxed_expensive_import else 0.0
+                )
+                if not relaxed_expensive_import and om == "AUTO":
                     prob += (
                         bd[t] + pv_ld[t]
                         >= float(s.load_baseline_w) + hp[t]
@@ -1434,7 +1454,27 @@ def solve_dispatch(
     status = prob.solve(solver)
     duration_ms = int((time.monotonic() - t_start) * 1000)
 
-    if pulp.LpStatus[status] != 'Optimal':
+    if pulp.LpStatus[status] != "Optimal":
+        if not relaxed_expensive_import:
+            logger.warning(
+                "solve_dispatch Infeasible, retry with relaxed_expensive_import "
+                "(grid may supply baseload in expensive slots)"
+            )
+            return solve_dispatch(
+                slots,
+                battery,
+                heat_pump,
+                grid,
+                ev_sessions,
+                vehicles,
+                current_soc_wh,
+                current_tuv_temp_c,
+                tuv_delta_stats=tuv_delta_stats,
+                operating_mode=operating_mode,
+                charge_commitment_prev_w=charge_commitment_prev_w,
+                planner_version=planner_version,
+                relaxed_expensive_import=True,
+            )
         raise RuntimeError(f"Solver: {pulp.LpStatus[status]}")
 
     # --- Post-processing ---
@@ -1597,6 +1637,7 @@ def solve_dispatch(
                 "planner_charge_commitment_penalty_czk_kwh": float(commit_pen),
             },
             "load_first_enabled": om == "AUTO",
+            "relaxed_expensive_import": relaxed_expensive_import,
             "charge_acquisition_buy_czk_kwh": charge_acquisition_czk_kwh,
             "charge_acquisition_cutoff_at": (
                 slots[0].charge_acquisition_cutoff_at.isoformat()
diff --git a/backend/tests/test_planning_dispatch_milp.py b/backend/tests/test_planning_dispatch_milp.py
index e725b44..f564e37 100644
--- a/backend/tests/test_planning_dispatch_milp.py
+++ b/backend/tests/test_planning_dispatch_milp.py
@@ -1285,6 +1285,47 @@ class AutoPassiveSelfConsumptionTests(unittest.TestCase):
         )
         self.assertEqual(len(results), 20)
 
+    def test_spot_low_acquisition_does_not_mark_all_slots_expensive(self) -> None:
+        """Spot + charge_acquisition ~0,9 nesmí z buy>acq udělat gi=0 pro dům ve všech slotech."""
+        base = datetime(2026, 5, 22, 10, 0, tzinfo=timezone.utc)
+        slots = [
+            PlanningSlot(
+                interval_start=base + timedelta(minutes=15 * i),
+                buy_price=2.5 + 0.1 * i,
+                sell_price=3.0,
+                pv_a_forecast_w=2000,
+                pv_b_forecast_w=3000,
+                load_baseline_w=2000,
+                ev1_connected=False,
+                ev2_connected=False,
+                allow_charge=False,
+                allow_discharge_export=False,
+                charge_acquisition_buy_czk_kwh=0.94,
+                future_sell_opportunity_czk_kwh=5.5,
+            )
+            for i in range(24)
+        ]
+        battery = _battery(uc_wh=64_000.0, min_pct=12.0, arb_pct=20.0)
+        battery.planner_terminal_soc_value_factor = 0.0
+        hp = SimpleNamespace(rated_heating_power_w=0, tuv_min_temp_c=45.0, tuv_target_temp_c=55.0)
+        grid = SimpleNamespace(max_import_power_w=17_000, max_export_power_w=13_500)
+        vehicles = [
+            SimpleNamespace(max_charge_power_w=0, battery_capacity_kwh=1.0, default_target_soc_pct=80.0),
+            SimpleNamespace(max_charge_power_w=0, battery_capacity_kwh=1.0, default_target_soc_pct=80.0),
+        ]
+        results, _, _ = solve_dispatch(
+            slots,
+            battery,
+            hp,
+            grid,
+            [None, None],
+            vehicles,
+            30_000.0,
+            50.0,
+            operating_mode="AUTO",
+        )
+        self.assertEqual(len(results), 24)
+
 
 class AutoPassiveNoLoadFollowingDischargeTests(unittest.TestCase):
     """AUTO bez allow_discharge_export: žádný export do sítě (Deye PASSIVE)."""
diff --git a/docs/04-modules/planning.md b/docs/04-modules/planning.md
index 181f593..7d06221 100644
--- a/docs/04-modules/planning.md
+++ b/docs/04-modules/planning.md
@@ -17,7 +17,7 @@
   - **Load-first (Deye, AUTO):** proměnné `pv_ld` (PV → load+EV+TČ), `pv_sp` (přebytek), `bc_pv` / `bc_gi`. Plná bilance `pv_a + pv_b + gi + bd = load + ev + hp + bc + ge`; `bc_pv + ge_pv ≤ pv_sp`; `gi ≤ load + bc_gi`; mimo `allow_discharge_export`: `bd ≤ load − pv_ld` a **`pv_ld ≥ load − gi − bd`**. Snapshot: `load_first_enabled=true`. Test `LoadFirstDispatchTests`.
   - **Tvrdé výkonové limity site/baterie:** `gi ≤ site_grid_connection.max_import_power_w` (breaker); **`bc_pv + bc_gi ≤ asset_battery.max_charge_power_w`**; **`ge ≤ max_export_power_w`** (proměnná `ge`, platí `ge = ge_pv + ge_bat`); **`bd + ge_bat ≤ asset_battery.max_discharge_power_w`** (vybíjení do domu + export z baterie nesmí současně překročit BMS). Dříve LP dovoloval import+nabíjení a dvojnásobné nabíjení; u prodeje hrozilo současné `bd` a `ge_bat` až 2× max discharge — viz `SitePowerCapTests`.
   - **Hodnota FVE (PV store value):** `ge_pv = 0`, pokud `sell < future_sell_opportunity − degradation` (ne `charge_acquisition` — u fixního KV1 by jinak blokoval export při sell 2 Kč). **Před prvním `sell < 0` v horizontu:** při `sell ≥ 0` smí `ge_pv` až do `pv_sp` (strategie BA81: vyvézt přes poledne, pak nabít z FVE v záporném okně). Výjimka **nucený vent** jen plná baterie. Testy `Home01PvStoreValueTests`, `PreNegativeSellExportTests`.
-  - **Drahý nákup → vlastní spotřeba z baterie:** mimo `allow_charge` platí `bd + pv_ld ≥ load_baseline + hp[t]` a `gi ≤ EV + hp[t]` (ne `hp_rated` — jinak infeasible když TČ v slotu neběží). Referenční buy = **min buy ≥ 0** v horizontu (záporný OTE slot jinak označí všechny sloty jako drahé → `gi=0` pro dům → Infeasible na home-01). Platí při `buy > ref_buy + degradace` **nebo** `buy > charge_acquisition + degradace`. Testy `AutoPassiveSelfConsumptionTests`, `test_negative_buy_in_horizon_does_not_block_all_grid_import`, `test_expensive_slot_uses_hp_variable_not_rated`.
+  - **Drahý nákup → vlastní spotřeba z baterie:** mimo `allow_charge` platí `bd + pv_ld ≥ load_baseline + hp[t]` a `gi ≤ EV + hp[t]` (ne `hp_rated`). **Spot:** drahý slot = `buy > min(buy≥0) + degradace`. **Fixní tarif (KV1):** navíc `buy > charge_acquisition + degradace` (`_horizon_fixed_tariff_like` — rozptyl buy &lt; 0,25 Kč/kWh). Na spotu **nesmí** `charge_acquisition` (~0,9 Kč) označit všechny sloty jako drahé → Infeasible (home-01). Při **Infeasible** solver jednou opakuje s `relaxed_expensive_import` (síť smí krmit baseload v drahých slotech; v `solver_params.inputs.relaxed_expensive_import=true`). Testy `AutoPassiveSelfConsumptionTests`, `test_spot_low_acquisition_does_not_mark_all_slots_expensive`, `test_negative_buy_in_horizon_does_not_block_all_grid_import`.
   - **Pole B při sell&lt;0 (home-01):** pokud `block_export_on_negative_sell = false`, LP nesmí vynutit `ge_pv = 0` (přebytek neriťitelného PV B). KV1 s `block_export = true` jen curtail A / nabíjení.
   - **`ref_buy_min` (brána exportu):** `min(buy_price)` horizontu — jen „existuje levný nákup?“, **ne** průměrná cena nabití přes hodiny. Export sloty: `sell > ref_buy_min + degradation` (spot). Viz [`planning-arbitrage-accounting.md`](planning-arbitrage-accounting.md).
   - Pokud `energy_to_fill <= 0` nebo `charge_slot_buffer = 0`: všechny sloty povoleny.