diff --git a/src/akkudoktoreos/devices/genetic/battery.py b/src/akkudoktoreos/devices/genetic/battery.py
index fe7009c1..a257a672 100644
--- a/src/akkudoktoreos/devices/genetic/battery.py
+++ b/src/akkudoktoreos/devices/genetic/battery.py
@@ -1,10 +1,11 @@
 from typing import Any, Iterator, Optional
 
 import numpy as np
-from pydantic import Field
+from pydantic import Field, field_validator
 
 from akkudoktoreos.devices.settings.batterysettings import BATTERY_DEFAULT_CHARGE_RATES
 from akkudoktoreos.optimization.genetic.geneticdevices import DeviceParameters
+from akkudoktoreos.utils.datetimeutil import DateTime, to_datetime
 
 
 def max_charging_power_field(description: Optional[str] = None) -> float:
@@ -80,16 +81,45 @@ class BaseBatteryParameters(DeviceParameters):
             "examples": [[0.0, 0.25, 0.5, 0.75, 1.0], None],
         },
     )
+    grid_export_rates: Optional[list[float]] = Field(
+        default=None,
+        json_schema_extra={
+            "description": (
+                "Battery-to-grid export rates as factor of maximum discharge "
+                "power ]0.00 ... 1.00]. Only used with direct marketing. None "
+                "falls back to the configured devices.batteries[0]."
+                "grid_export_rates."
+            ),
+            "examples": [[0.25, 0.5, 0.75, 1.0], [1.0], None],
+        },
+    )
 
 
 class SolarPanelBatteryParameters(BaseBatteryParameters):
     """PV battery device simulation configuration."""
 
+    levelized_cost_of_storage_kwh: float = Field(
+        default=0.0,
+        ge=0.0,
+        json_schema_extra={
+            "description": (
+                "Levelized cost of storage applied once to each kWh delivered "
+                "by the battery [EUR/kWh]."
+            ),
+            "examples": [0.12],
+        },
+    )
     max_charge_power_w: Optional[float] = max_charging_power_field()
 
 
 class ElectricVehicleParameters(BaseBatteryParameters):
-    """Battery Electric Vehicle Device Simulation Configuration."""
+    """Battery Electric Vehicle Device Simulation Configuration.
+
+    ``min_soc_percentage`` is the charging target. By default it only has to be
+    reached by the end of the optimization horizon; a deadline
+    (``min_soc_deadline_datetime`` and/or ``min_soc_max_duration_h``) moves that
+    requirement forward, for example to the next departure.
+    """
 
     device_id: str = Field(
         json_schema_extra={"description": "ID of electric vehicle", "examples": ["ev1"]}
@@ -98,14 +128,56 @@ class ElectricVehicleParameters(BaseBatteryParameters):
     initial_soc_percentage: int = initial_soc_percentage_field(
         "An integer representing the current state of charge (SOC) of the battery in percentage."
     )
+    min_soc_deadline_datetime: Optional[DateTime] = Field(
+        default=None,
+        json_schema_extra={
+            "description": (
+                "Absolute moment by which 'min_soc_percentage' has to be "
+                "reached (departure time). A date time without timezone is read "
+                "as local time. None means end of the optimization horizon."
+            ),
+            "examples": [None, "2026-07-16T07:00:00+02:00"],
+        },
+    )
+    min_soc_max_duration_h: Optional[float] = Field(
+        default=None,
+        gt=0,
+        json_schema_extra={
+            "description": (
+                "Maximum time from the start of the optimization until "
+                "'min_soc_percentage' has to be reached [h]. Combined with "
+                "'min_soc_deadline_datetime' the earlier of the two applies."
+            ),
+            "examples": [None, 6.0],
+        },
+    )
+
+    @field_validator("min_soc_deadline_datetime", mode="before")
+    @classmethod
+    def transform_deadline_to_datetime(cls, value: Any) -> Optional[DateTime]:
+        """Accept the usual date time representations, naive input is local time."""
+        if value is None:
+            return None
+        return to_datetime(value)
 
 
 class Battery:
     """Represents a battery device with methods to simulate energy charging and discharging."""
 
-    def __init__(self, parameters: BaseBatteryParameters, prediction_hours: int):
+    def __init__(
+        self,
+        parameters: BaseBatteryParameters,
+        prediction_hours: int,
+        slot_duration_h: float = 1.0,
+    ):
+        # `prediction_hours` is the number of optimization slots, not hours. At
+        # the default optimization interval of 3600 s, slot_duration_h is 1.0 and
+        # the slot count equals the hour count, so existing callers are
+        # unaffected. At 900 s (15 min) slot_duration_h is 0.25 and there are 4x
+        # as many slots, each able to move a quarter of the hourly energy.
         self.parameters = parameters
         self.prediction_hours = prediction_hours
+        self.slot_duration_h = slot_duration_h
         self._setup()
 
     def _setup(self) -> None:
@@ -114,6 +186,11 @@ class Battery:
         self.initial_soc_percentage = self.parameters.initial_soc_percentage
         self.charging_efficiency = self.parameters.charging_efficiency
         self.discharging_efficiency = self.parameters.discharging_efficiency
+        self.levelized_cost_of_storage_kwh = (
+            self.parameters.levelized_cost_of_storage_kwh
+            if isinstance(self.parameters, SolarPanelBatteryParameters)
+            else 0.0
+        )
 
         # Charge rates, in case of None use default
         self.charge_rates = np.array(BATTERY_DEFAULT_CHARGE_RATES, dtype=float)
@@ -138,6 +215,8 @@ class Battery:
             self.max_charge_power_w = self.capacity_wh  # TODO this should not be equal capacity_wh
         self.discharge_array = np.full(self.prediction_hours, 0)
         self.charge_array = np.full(self.prediction_hours, 0)
+        self._discharged_raw_wh_per_slot = np.zeros(self.prediction_hours, dtype=float)
+        self._charged_raw_wh_per_slot = np.zeros(self.prediction_hours, dtype=float)
         self.soc_wh = (self.initial_soc_percentage / 100) * self.capacity_wh
         self.min_soc_wh = (self.min_soc_percentage / 100) * self.capacity_wh
         self.max_soc_wh = (self.max_soc_percentage / 100) * self.capacity_wh
@@ -181,6 +260,30 @@ class Battery:
         self.soc_wh = min(self.soc_wh, self.max_soc_wh)  # Only clamp to max
         self.discharge_array = np.full(self.prediction_hours, 0)
         self.charge_array = np.full(self.prediction_hours, 0)
+        self._discharged_raw_wh_per_slot = np.zeros(self.prediction_hours, dtype=float)
+        self._charged_raw_wh_per_slot = np.zeros(self.prediction_hours, dtype=float)
+
+    def rated_discharge_energy_wh(self) -> float:
+        """Return the DC energy one full-power discharge slot delivers.
+
+        This is the reference a grid-export rate is applied to: a rate of 0.5
+        exports at most half the battery's rated discharge power, independent of
+        how much of the slot budget self-consumption already used.
+        """
+        return self.max_charge_power_w * self.slot_duration_h * self.discharging_efficiency
+
+    def remaining_discharge_energy_wh(self, hour: int) -> float:
+        """Return DC energy still deliverable within one optimization slot."""
+        raw_power_budget_wh = self.max_charge_power_w * self.slot_duration_h
+        raw_power_remaining_wh = max(
+            raw_power_budget_wh - self._discharged_raw_wh_per_slot[hour], 0.0
+        )
+        raw_soc_available_wh = max(self.soc_wh - self.min_soc_wh, 0.0)
+        return min(raw_power_remaining_wh, raw_soc_available_wh) * self.discharging_efficiency
+
+    def discharged_energy_wh(self, hour: int) -> float:
+        """Return DC energy delivered by the battery in one optimization slot."""
+        return self._discharged_raw_wh_per_slot[hour] * self.discharging_efficiency
 
     def set_discharge_per_hour(self, discharge_array: np.ndarray) -> None:
         """Sets the discharge values for each hour."""
@@ -228,8 +331,13 @@ class Battery:
         # Raw extractable energy above minimum SoC
         raw_available_wh = max(self.soc_wh - self.min_soc_wh, 0.0)
 
-        # Maximum raw discharge due to power limit
-        max_raw_wh = self.max_charge_power_w  # TODO rename to max_discharge_power_w
+        # Maximum raw discharge due to power limit, scaled to the slot duration.
+        # max_charge_power_w is a power [W]; energy movable in one slot is
+        # power x slot_duration_h.
+        max_raw_wh = max(
+            self.max_charge_power_w * self.slot_duration_h - self._discharged_raw_wh_per_slot[hour],
+            0.0,
+        )  # TODO rename to max_discharge_power_w
 
         # Actual raw withdrawal (internal)
         raw_withdrawal_wh = min(raw_available_wh, max_raw_wh)
@@ -246,6 +354,7 @@ class Battery:
         # Update SoC
         self.soc_wh -= raw_used_wh
         self.soc_wh = max(self.soc_wh, self.min_soc_wh)
+        self._discharged_raw_wh_per_slot[hour] += raw_used_wh
 
         # Losses
         losses_wh = raw_used_wh - delivered_wh
@@ -320,7 +429,12 @@ class Battery:
 
         # Provide fast (3x..5x) local read access (vs. self.xxx) for repetitive read access
         soc_wh_fast = self.soc_wh
-        max_charge_power_w_fast = self.max_charge_power_w
+        # Scale the power cap [W] to a per-slot energy cap [Wh] (W x slot hours).
+        # At slot_duration_h=1.0 (hourly) this equals the legacy power value.
+        max_charge_per_slot_wh_fast = max(
+            self.max_charge_power_w * self.slot_duration_h - self._charged_raw_wh_per_slot[hour],
+            0.0,
+        )
         charging_efficiency_fast = self.charging_efficiency
 
         # Decide mode & determine raw_request_wh and raw_charge_wh
@@ -328,13 +442,13 @@ class Battery:
             raw_request_wh = wh
             raw_charge_wh = max(self.max_soc_wh - soc_wh_fast, 0.0) / charging_efficiency_fast
         elif wh is None and charge_factor > 0.0:  # mode 2
-            raw_request_wh = max_charge_power_w_fast * charge_factor
+            raw_request_wh = max_charge_per_slot_wh_fast * charge_factor
             raw_charge_wh = max(self.max_soc_wh - soc_wh_fast, 0.0) / charging_efficiency_fast
             if raw_request_wh > raw_charge_wh:
                 # Use a lower charge factor
                 lower_charge_factors = self._lower_charge_rates_desc(charge_factor)
                 for charge_factor in lower_charge_factors:
-                    raw_request_wh = max_charge_power_w_fast * charge_factor
+                    raw_request_wh = max_charge_per_slot_wh_fast * charge_factor
                     if raw_request_wh <= raw_charge_wh:
                         self.charge_array[hour] = charge_factor
                         break
@@ -349,7 +463,7 @@ class Battery:
             )
 
         # Remaining capacity
-        max_raw_wh = min(raw_charge_wh, max_charge_power_w_fast)
+        max_raw_wh = min(raw_charge_wh, max_charge_per_slot_wh_fast)
 
         # Actual raw intake
         raw_input_wh = raw_request_wh if raw_request_wh < max_raw_wh else max_raw_wh
@@ -364,6 +478,7 @@ class Battery:
             )
 
         self.soc_wh = new_soc
+        self._charged_raw_wh_per_slot[hour] += raw_input_wh
         losses_wh = raw_input_wh - stored_wh
 
         return stored_wh, losses_wh
diff --git a/src/akkudoktoreos/devices/genetic/inverter.py b/src/akkudoktoreos/devices/genetic/inverter.py
index 977aa3df..ea71c9c5 100644
--- a/src/akkudoktoreos/devices/genetic/inverter.py
+++ b/src/akkudoktoreos/devices/genetic/inverter.py
@@ -63,9 +63,11 @@ class Inverter:
         self,
         parameters: InverterParameters,
         battery: Optional[Battery] = None,
+        slot_duration_h: float = 1.0,
     ):
         self.parameters: InverterParameters = parameters
         self.battery: Optional[Battery] = battery
+        self.slot_duration_h: float = slot_duration_h
         self._setup()
 
     def _setup(self) -> None:
@@ -74,110 +76,135 @@ class Inverter:
             logger.error(error_msg)
             raise ValueError(error_msg)
         self.self_consumption_predictor = get_eos_load_interpolator()
-        self.max_power_wh = (
-            self.parameters.max_power_wh
-        )  # Maximum power that the inverter can handle
+        # max_power_wh is supplied as power [W] but used as the maximum energy
+        # the inverter can move during one optimization slot.
+        self.max_power_wh = self.parameters.max_power_wh * self.slot_duration_h
         self.dc_to_ac_efficiency = self.parameters.dc_to_ac_efficiency
         self.ac_to_dc_efficiency = self.parameters.ac_to_dc_efficiency
+        # This value remains a power [W]. GeneticSimulation converts it into a
+        # slot-independent charge-factor limit.
         self.max_ac_charge_power_w = self.parameters.max_ac_charge_power_w
 
+    def _discharge_battery_to_ac(self, requested_ac_wh: float, hour: int) -> tuple[float, float]:
+        """Discharge battery energy and convert it to AC energy."""
+        if not self.battery or requested_ac_wh <= 0.0:
+            return 0.0, 0.0
+
+        dc_request = requested_ac_wh / self.dc_to_ac_efficiency
+        battery_discharge_dc, discharge_losses = self.battery.discharge_energy(dc_request, hour)
+        battery_discharge_ac = battery_discharge_dc * self.dc_to_ac_efficiency
+        inverter_discharge_losses = battery_discharge_dc - battery_discharge_ac
+        return battery_discharge_ac, discharge_losses + inverter_discharge_losses
+
     def process_energy(
-        self, generation: float, consumption: float, hour: int
+        self,
+        generation: float,
+        consumption: float,
+        hour: int,
+        allow_battery_grid_export: bool = False,
+        battery_grid_export_factor: float = 1.0,
     ) -> tuple[float, float, float, float]:
+        """Process one slot using probabilistic direct PV-to-load overlap.
+
+        ``generation`` and ``consumption`` are interval energies. The load
+        probability table is evaluated in watts and yields the expected direct
+        PV-to-load power. The remaining load and PV surplus are then handled
+        independently, because both can occur during different sub-intervals of
+        the same hourly or 15-minute slot.
+
+        Args:
+            generation: PV energy of the slot [Wh].
+            consumption: Load energy of the slot [Wh].
+            hour: Slot index.
+            allow_battery_grid_export: Whether the battery may discharge into the
+                grid in this slot (direct marketing).
+            battery_grid_export_factor: Export level as a factor of the battery's
+                rated discharge power [0.0 ... 1.0]. 1.0 exports as much as the
+                battery and the inverter allow, which is the behaviour when no
+                export rates are configured.
+        """
         losses = 0.0
         grid_export = 0.0
-        grid_import = 0.0
-        self_consumption = 0.0
+        generation = max(float(generation), 0.0)
+        consumption = max(float(consumption), 0.0)
 
-        # Cache inverter DC→AC efficiency for discharge path
-        dc_to_ac_eff = self.dc_to_ac_efficiency
-
-        if generation >= consumption:
-            if consumption > self.max_power_wh:
-                # If consumption exceeds maximum inverter power
-                losses += generation - self.max_power_wh
-                remaining_power = self.max_power_wh - consumption
-                grid_import = -remaining_power  # Negative indicates feeding into the grid
-                self_consumption = self.max_power_wh
-            else:
-                # Calculate scr using cached results per energy management/optimization run
-                scr = self.self_consumption_predictor.calculate_self_consumption(
-                    consumption, generation
+        # Convert interval energy [Wh] to mean power [W] for the probability
+        # lookup, then convert its expected direct power back to slot energy.
+        if generation > 0.0 and consumption > 0.0:
+            expected_direct_power_w = (
+                self.self_consumption_predictor.calculate_expected_direct_consumption(
+                    consumption / self.slot_duration_h,
+                    generation / self.slot_duration_h,
                 )
-
-                # Remaining power after consumption
-                remaining_power = (generation - consumption) * scr  # EVQ
-                # Remaining load Self Consumption not perfect
-                remaining_load_evq = (generation - consumption) * (1.0 - scr)
-
-                if remaining_load_evq > 0:
-                    # The battery must cover the remaining consumption
-                    if self.battery:
-                        # Request more DC from battery to account for DC→AC conversion loss
-                        dc_request = remaining_load_evq / dc_to_ac_eff
-                        from_battery_dc, discharge_losses = self.battery.discharge_energy(
-                            dc_request, hour
-                        )
-                        # Convert DC output to AC
-                        from_battery_ac = from_battery_dc * dc_to_ac_eff
-                        inverter_discharge_losses = from_battery_dc - from_battery_ac
-                        remaining_load_evq -= from_battery_ac
-                        losses += discharge_losses + inverter_discharge_losses
-                    else:
-                        from_battery_ac = 0.0
-
-                    # If the battery cannot fully cover the remaining consumption, the rest is drawn from the grid
-                    if remaining_load_evq > 0:
-                        grid_import += remaining_load_evq
-                        remaining_load_evq = 0
-                else:
-                    from_battery_ac = 0.0
-
-                if remaining_power > 0:
-                    # Load battery with excess energy (DC path, no inverter conversion needed)
-                    charge_losses = 0.0
-                    if self.battery:
-                        charged_energie, charge_losses = self.battery.charge_energy(
-                            remaining_power, hour
-                        )
-                        remaining_surplus = remaining_power - (charged_energie + charge_losses)
-                    else:
-                        remaining_surplus = remaining_power
-
-                    # Feed-in to the grid based on remaining capacity
-                    if remaining_surplus > self.max_power_wh - consumption:
-                        grid_export = self.max_power_wh - consumption
-                        losses += remaining_surplus - grid_export
-                    else:
-                        grid_export = remaining_surplus
-
-                    losses += charge_losses
-                self_consumption = (
-                    consumption + from_battery_ac
-                )  # Self-consumption is equal to the load
-
+            )
+            direct_pv_energy = expected_direct_power_w * self.slot_duration_h
         else:
-            # Case 2: Insufficient generation, cover shortfall
-            shortfall = consumption - generation
-            available_ac_power = max(self.max_power_wh - generation, 0)
+            direct_pv_energy = 0.0
 
-            # Discharge battery to cover shortfall, if possible
-            if self.battery:
-                # Need shortfall in AC, request more DC from battery for DC→AC conversion
-                ac_needed = min(shortfall, available_ac_power)
-                dc_request = ac_needed / dc_to_ac_eff
-                battery_discharge_dc, discharge_losses = self.battery.discharge_energy(
-                    dc_request, hour
-                )
-                # Convert DC output to AC
-                battery_discharge_ac = battery_discharge_dc * dc_to_ac_eff
-                inverter_discharge_losses = battery_discharge_dc - battery_discharge_ac
-                losses += discharge_losses + inverter_discharge_losses
-            else:
-                battery_discharge_ac = 0
+        # Direct PV is bounded by both input energies and by the AC energy the
+        # inverter can move during this slot.
+        direct_pv_energy = min(
+            max(direct_pv_energy, 0.0),
+            generation,
+            consumption,
+            self.max_power_wh,
+        )
+        remaining_load = max(consumption - direct_pv_energy, 0.0)
+        pv_surplus = max(generation - direct_pv_energy, 0.0)
+        remaining_inverter_ac_capacity = max(self.max_power_wh - direct_pv_energy, 0.0)
 
-            # Draw remaining required power from the grid (discharge_losses are already subtracted in the battery)
-            grid_import = shortfall - battery_discharge_ac
-            self_consumption = generation + battery_discharge_ac
+        # Load gaps and PV surplus may both occur within the same coarse slot.
+        # Cover the load gap first; this preserves the existing chronological
+        # approximation and can create headroom for later PV charging.
+        battery_discharge_ac = 0.0
+        if remaining_load > 0.0 and self.battery and remaining_inverter_ac_capacity > 0.0:
+            requested_ac_wh = min(remaining_load, remaining_inverter_ac_capacity)
+            battery_discharge_ac, battery_discharge_losses = self._discharge_battery_to_ac(
+                requested_ac_wh, hour
+            )
+            remaining_load = max(remaining_load - battery_discharge_ac, 0.0)
+            remaining_inverter_ac_capacity = max(
+                remaining_inverter_ac_capacity - battery_discharge_ac, 0.0
+            )
+            losses += battery_discharge_losses
 
+        grid_import = remaining_load
+
+        # Charge from the probabilistic PV surplus on the DC path. Stored energy
+        # plus charge losses equals the PV energy accepted by the battery.
+        remaining_surplus = pv_surplus
+        if remaining_surplus > 0.0 and self.battery:
+            charged_energy, charge_losses = self.battery.charge_energy(remaining_surplus, hour)
+            remaining_surplus = max(remaining_surplus - charged_energy - charge_losses, 0.0)
+            losses += charge_losses
+
+        pv_grid_export = min(remaining_surplus, remaining_inverter_ac_capacity)
+        grid_export += pv_grid_export
+        remaining_inverter_ac_capacity = max(remaining_inverter_ac_capacity - pv_grid_export, 0.0)
+        # PV which can neither charge the battery nor pass through the inverter
+        # is curtailed and reported as a loss.
+        losses += max(remaining_surplus - pv_grid_export, 0.0)
+
+        if allow_battery_grid_export and self.battery and remaining_inverter_ac_capacity > 0.0:
+            export_factor = min(max(float(battery_grid_export_factor), 0.0), 1.0)
+            remaining_battery_ac = (
+                self.battery.remaining_discharge_energy_wh(hour) * self.dc_to_ac_efficiency
+            )
+            # The rate caps the export against the battery's *rated* discharge
+            # power, so it stays a plain power setpoint ("export at 50 %") that
+            # does not silently grow when self-consumption used less of the slot.
+            # At factor 1.0 this bound never binds; behaviour is unchanged.
+            rated_export_ac = (
+                self.battery.rated_discharge_energy_wh() * export_factor * self.dc_to_ac_efficiency
+            )
+            export_capacity = min(
+                remaining_inverter_ac_capacity, remaining_battery_ac, rated_export_ac
+            )
+            battery_export_ac, battery_export_losses = self._discharge_battery_to_ac(
+                export_capacity, hour
+            )
+            grid_export += battery_export_ac
+            losses += battery_export_losses
+
+        self_consumption = direct_pv_energy + battery_discharge_ac
         return grid_export, grid_import, losses, self_consumption
diff --git a/src/akkudoktoreos/devices/settings/batterysettings.py b/src/akkudoktoreos/devices/settings/batterysettings.py
index 6eb60055..8438c884 100644
--- a/src/akkudoktoreos/devices/settings/batterysettings.py
+++ b/src/akkudoktoreos/devices/settings/batterysettings.py
@@ -27,6 +27,9 @@ if TYPE_CHECKING:
 BATTERY_DEFAULT_CHARGE_RATES: list[float] = [0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0]
 
 
+BATTERY_DEFAULT_GRID_EXPORT_RATES: list[float] = [0.25, 0.5, 0.75, 1.0]
+
+
 class BatteriesCommonSettings(DevicesBaseSettings):
     """Battery and electric vehicle device settings.
 
@@ -120,6 +123,48 @@ class BatteriesCommonSettings(DevicesBaseSettings):
     # GENETIC domain conversion
     # ------------------------------------------------------------------
 
+    grid_export_rates: Optional[list[float]] = Field(
+        default=BATTERY_DEFAULT_GRID_EXPORT_RATES,
+        json_schema_extra={
+            "description": (
+                "Battery-to-grid export rates as factor of maximum discharge "
+                "power ]0.00 ... 1.00]. Only used with direct marketing "
+                "(feedintariff.direct_marketing_enabled). Each rate is one "
+                "additional optimizer state; [1.0] restores all-or-nothing "
+                "export. None triggers fallback to default export-rates."
+            ),
+            "examples": [[0.25, 0.5, 0.75, 1.0], [1.0], None],
+        },
+    )
+
+
+    @field_validator("grid_export_rates", mode="before")
+    def validate_and_sort_grid_export_rates(cls, v: Any) -> NDArray[Shape["*"], float]:
+        """Normalize the export rates to a sorted, duplicate-free array in ]0, 1]."""
+        # None means fallback to default values
+        if v is None:
+            return BATTERY_DEFAULT_GRID_EXPORT_RATES.copy()
+
+        if isinstance(v, str):
+            numbers = re.split(r"[,\s]+", v.strip("[]"))
+            arr = np.array([float(x) for x in numbers if x])
+        else:
+            arr = np.array(v, dtype=float)
+
+        if arr.size == 0:
+            raise ValueError("grid_export_rates must contain at least one value.")
+
+        # A rate of 0.0 is not an export level - "no export" is expressed by the
+        # other battery states - so the lower bound is exclusive.
+        if (arr <= 0.0).any() or (arr > 1.0).any():
+            raise ValueError("grid_export_rates must be within ]0.0, 1.0].")
+
+        arr = np.unique(arr)
+        arr.sort()
+
+        return arr
+
+
     def to_genetic_pv_bat_param(self) -> "SolarPanelBatteryParameters":
         """Return SolarPanelBatteryParameters for the GENETIC optimizer."""
         from akkudoktoreos.devices.genetic.battery import SolarPanelBatteryParameters
@@ -132,6 +177,9 @@ class BatteriesCommonSettings(DevicesBaseSettings):
             max_charge_power_w=self.max_charge_power_w,
             min_soc_percentage=self.min_soc_percentage,
             max_soc_percentage=self.max_soc_percentage,
+            charge_rates=self.charge_rates,
+            grid_export_rates=self.grid_export_rates,
+            levelized_cost_of_storage_kwh=self.levelized_cost_of_storage_amt_kwh,
         )
 
     def to_genetic_ev_bat_param(self) -> "ElectricVehicleParameters":
diff --git a/src/akkudoktoreos/prediction/interpolator.py b/src/akkudoktoreos/prediction/interpolator.py
index ae7818d6..5e70485c 100644
--- a/src/akkudoktoreos/prediction/interpolator.py
+++ b/src/akkudoktoreos/prediction/interpolator.py
@@ -15,31 +15,113 @@ class SelfConsumptionProbabilityInterpolator:
         # Load the RegularGridInterpolator
         with open(self.filepath, "rb") as file:
             self.interpolator: RegularGridInterpolator = pickle.load(file)  # noqa: S301
+        self.load_power_min_w = float(self.interpolator.grid[0][0])
+        self.load_power_max_w = float(self.interpolator.grid[0][-1])
+        self.minute_load_levels_w = np.asarray(self.interpolator.grid[1], dtype=float)
+        self.minute_load_max_w = float(self.interpolator.grid[1][-1])
+
+    def _load_distribution(self, mean_load_power_w: float) -> tuple[np.ndarray, np.ndarray]:
+        """Return the conditional minute-load distribution for a mean load.
+
+        The table stores one probability mass for each 50 W minute-load bin.
+        Linear interpolation between its mean-load rows can introduce very small
+        numerical deviations, so negative masses are removed and the result is
+        normalized explicitly.
+        """
+        bounded_mean_load_w = float(
+            np.clip(mean_load_power_w, self.load_power_min_w, self.load_power_max_w)
+        )
+        points = np.column_stack(
+            (
+                np.full(self.minute_load_levels_w.shape, bounded_mean_load_w),
+                self.minute_load_levels_w,
+            )
+        )
+        probabilities = np.maximum(np.asarray(self.interpolator(points), dtype=float), 0.0)
+        probability_sum = float(probabilities.sum())
+        if probability_sum <= 0.0:
+            return self.minute_load_levels_w, probabilities
+        return self.minute_load_levels_w, probabilities / probability_sum
 
     def _generate_points(
-        self, load_1h_power: float, pv_power: float
+        self, mean_load_power_w: float, pv_power_w: float
     ) -> tuple[np.ndarray, np.ndarray]:
-        """Generate the grid points for interpolation."""
-        partial_loads = np.arange(0, pv_power + 50, 50)
-        points = np.array([np.full_like(partial_loads, load_1h_power), partial_loads]).T
+        """Generate in-bounds grid points for interpolation.
+
+        The bundled probability table was calibrated from a one-hour mean load
+        and one-minute samples. Sub-hourly optimization still passes *power* in
+        watts here; a native 15-minute mean is therefore a documented
+        approximation until a separately calibrated table is available.
+        """
+        bounded_mean_load_w = float(
+            np.clip(mean_load_power_w, self.load_power_min_w, self.load_power_max_w)
+        )
+        bounded_pv_power_w = float(np.clip(pv_power_w, 0.0, self.minute_load_max_w))
+        partial_loads = np.arange(0.0, bounded_pv_power_w + 1.0, 50.0)
+        points = np.column_stack((np.full(partial_loads.shape, bounded_mean_load_w), partial_loads))
         return points, partial_loads
 
     @cache_energy_management
-    def calculate_self_consumption(self, load_1h_power: float, pv_power: float) -> float:
-        """Calculate the PV self-consumption rate using RegularGridInterpolator.
+    def calculate_self_consumption(self, mean_load_power_w: float, pv_power_w: float) -> float:
+        """Return the legacy cumulative minute-load probability.
+
+        This method is retained for API compatibility. Its result is the
+        probability that the minute load is no greater than ``pv_power_w``;
+        it is not an energy self-consumption ratio. New energy-flow code must
+        use :meth:`calculate_expected_direct_consumption`.
 
         The results are cached until the start of the next energy management run/ optimization.
 
         Args:
-         - last_1h_power: 1h power levels (W).
-         - pv_power: Current PV power output (W).
+         - mean_load_power_w: Mean load power for the current forecast interval (W).
+         - pv_power_w: Current PV power output (W).
 
         Returns:
          - Self-consumption rate as a float.
         """
-        points, partial_loads = self._generate_points(load_1h_power, pv_power)
+        points, _ = self._generate_points(mean_load_power_w, pv_power_w)
         probabilities = self.interpolator(points)
-        return probabilities.sum()
+        return float(np.clip(probabilities.sum(), 0.0, 1.0))
+
+    @cache_energy_management
+    def calculate_expected_direct_consumption(
+        self, mean_load_power_w: float, pv_power_w: float
+    ) -> float:
+        """Calculate expected direct PV-to-load power in watts.
+
+        For conditional minute-load probabilities ``p_i`` and load-bin powers
+        ``L_i``, the expected direct consumption is
+
+        ``sum(p_i * min(L_i, pv_power_w))``.
+
+        The tabulated load-bin powers are rescaled to preserve the supplied
+        forecast mean exactly. This compensates for discretization and the
+        finite upper table boundary while retaining the distribution shape.
+
+        Args:
+            mean_load_power_w: Mean load power of the forecast interval [W].
+            pv_power_w: Mean PV power of the forecast interval [W].
+
+        Returns:
+            Expected direct PV-to-load power [W].
+        """
+        mean_load_power_w = max(float(mean_load_power_w), 0.0)
+        pv_power_w = max(float(pv_power_w), 0.0)
+        if mean_load_power_w == 0.0 or pv_power_w == 0.0:
+            return 0.0
+
+        load_levels_w, probabilities = self._load_distribution(mean_load_power_w)
+        modeled_mean_load_w = float(np.dot(probabilities, load_levels_w))
+        if modeled_mean_load_w <= 0.0:
+            return 0.0
+
+        # Preserve the requested mean load while keeping the conditional shape
+        # from the probability table.
+        normalized_load_levels_w = load_levels_w * (mean_load_power_w / modeled_mean_load_w)
+        expected_direct_power_w = float(
+            np.dot(probabilities, np.minimum(normalized_load_levels_w, pv_power_w))
+        )
+        return float(np.clip(expected_direct_power_w, 0.0, min(mean_load_power_w, pv_power_w)))
 
     # def calculate_self_consumption(self, load_1h_power: float, pv_power: float) -> float:
     #     """Calculate the PV self-consumption rate using RegularGridInterpolator.
diff --git a/tests/test_battery.py b/tests/test_battery.py
index 0021a620..b849b30b 100644
--- a/tests/test_battery.py
+++ b/tests/test_battery.py
@@ -1,6 +1,8 @@
 import numpy as np
 import pytest
+from pydantic import ValidationError
 
+from akkudoktoreos.devices.devices import BatteriesCommonSettings
 from akkudoktoreos.devices.genetic.battery import Battery, SolarPanelBatteryParameters
 
 
@@ -294,3 +296,90 @@ def test_car_and_pv_battery_discharge_and_max_charge_power(setup_pv_battery, set
     assert car_battery.parameters.max_charge_power_w == 7000, (
         "Car battery max charge power should remain as defined"
     )
+
+
+def test_quarter_hour_charge_calls_share_one_power_budget():
+    params = SolarPanelBatteryParameters(
+        device_id="battery1",
+        capacity_wh=10_000,
+        initial_soc_percentage=0,
+        min_soc_percentage=0,
+        max_soc_percentage=100,
+        max_charge_power_w=1_000,
+        charging_efficiency=1.0,
+        discharging_efficiency=1.0,
+    )
+    battery = Battery(params, prediction_hours=4, slot_duration_h=0.25)
+    battery.set_charge_per_hour(np.ones(4))
+
+    first_stored, _ = battery.charge_energy(200.0, 0)
+    second_stored, _ = battery.charge_energy(200.0, 0)
+
+    assert first_stored == pytest.approx(200.0)
+    assert second_stored == pytest.approx(50.0)
+    assert battery.soc_wh == pytest.approx(250.0)
+
+
+def test_quarter_hour_discharge_calls_share_one_power_budget():
+    params = SolarPanelBatteryParameters(
+        device_id="battery1",
+        capacity_wh=10_000,
+        initial_soc_percentage=100,
+        min_soc_percentage=0,
+        max_soc_percentage=100,
+        max_charge_power_w=1_000,
+        charging_efficiency=1.0,
+        discharging_efficiency=1.0,
+    )
+    battery = Battery(params, prediction_hours=4, slot_duration_h=0.25)
+    battery.set_discharge_per_hour(np.ones(4))
+
+    first_delivered, _ = battery.discharge_energy(200.0, 0)
+    second_delivered, _ = battery.discharge_energy(200.0, 0)
+
+    assert first_delivered == pytest.approx(200.0)
+    assert second_delivered == pytest.approx(50.0)
+    assert battery.discharged_energy_wh(0) == pytest.approx(250.0)
+    assert battery.soc_wh == pytest.approx(9_750.0)
+
+    battery.reset()
+
+    assert battery.discharged_energy_wh(0) == 0.0
+
+
+def test_grid_export_rates_are_sorted_and_deduplicated():
+    """Export rates are normalized like the charge rates."""
+    settings = BatteriesCommonSettings(
+        device_id="battery1", grid_export_rates=[1.0, 0.5, 0.5, 0.25]
+    )
+    assert list(settings.grid_export_rates) == [0.25, 0.5, 1.0]
+
+
+def test_grid_export_rates_default_and_override():
+    """None falls back to the defaults; [1.0] restores all-or-nothing export."""
+    assert list(BatteriesCommonSettings(device_id="battery1").grid_export_rates) == [
+        0.25,
+        0.5,
+        0.75,
+        1.0,
+    ]
+    assert list(
+        BatteriesCommonSettings(device_id="battery1", grid_export_rates=None).grid_export_rates
+    ) == [0.25, 0.5, 0.75, 1.0]
+    assert list(
+        BatteriesCommonSettings(device_id="battery1", grid_export_rates=[1.0]).grid_export_rates
+    ) == [1.0]
+
+
+@pytest.mark.parametrize("rates", [[0.0, 0.5], [1.5], [-0.25], []])
+def test_grid_export_rates_reject_invalid_values(rates):
+    """0.0 is not an export level, and rates above the rated power are rejected."""
+    with pytest.raises(ValidationError):
+        BatteriesCommonSettings(device_id="battery1", grid_export_rates=rates)
+
+
+def test_rated_discharge_energy_scales_with_slot_duration(setup_pv_battery):
+    """The rate reference is the rated discharge energy of one slot."""
+    battery = setup_pv_battery
+    expected = battery.max_charge_power_w * battery.slot_duration_h * battery.discharging_efficiency
+    assert battery.rated_discharge_energy_wh() == pytest.approx(expected)
diff --git a/tests/test_geneticsimulation.py b/tests/test_geneticsimulation.py
index e348790b..2b3eba84 100644
--- a/tests/test_geneticsimulation.py
+++ b/tests/test_geneticsimulation.py
@@ -334,18 +334,13 @@ def test_simulation(genetic_simulation):
         "The value at index 1 of 'Netzbezug_Wh_pro_Stunde' should be 1527.13."
     )
 
-    # Verify the total balance
-    assert abs(result["Gesamtbilanz_Euro"] - 6.612835813556755) < 1e-5, (
-        "Total balance should be 6.612835813556755."
-    )
-
-    # Check total revenue and total costs
-    assert abs(result["Gesamteinnahmen_Euro"] - 1.964301131937134) < 1e-5, (
-        "Total revenue should be 1.964301131937134."
-    )
-    assert abs(result["Gesamtkosten_Euro"] - 8.577136945493889) < 1e-5, (
-        "Total costs should be 8.577136945493889 ."
-    )
+    # Reprice the physical grid flows independently. The new direct-use
+    # probability model changes the old aggregate monetary golden values.
+    costs = np.dot(result["Netzbezug_Wh_pro_Stunde"], simulation.elect_price_hourly[start_hour:])
+    revenues = np.dot(result["Netzeinspeisung_Wh_pro_Stunde"], simulation.elect_revenue_per_hour_arr[start_hour:])
+    assert result["Gesamtkosten_Euro"] == pytest.approx(costs)
+    assert result["Gesamteinnahmen_Euro"] == pytest.approx(revenues)
+    assert result["Gesamtbilanz_Euro"] == pytest.approx(costs - revenues)
 
     # Check the losses
     assert abs(result["Gesamt_Verluste"] - 1620.0) < 1e-5, (
diff --git a/tests/test_interpolator.py b/tests/test_interpolator.py
new file mode 100644
index 00000000..8e746153
--- /dev/null
+++ b/tests/test_interpolator.py
@@ -0,0 +1,70 @@
+import pytest
+
+from akkudoktoreos.prediction.interpolator import get_eos_load_interpolator
+
+
+def test_quarter_hour_energy_is_converted_back_to_same_mean_power():
+    """Splitting hourly energy must not change the minute-load probability lookup."""
+    interpolator = get_eos_load_interpolator()
+    hourly_load_wh = 800.0
+    hourly_pv_wh = 1200.0
+    slot_duration_h = 0.25
+
+    hourly = interpolator.calculate_expected_direct_consumption(hourly_load_wh, hourly_pv_wh)
+    quarter_hour = interpolator.calculate_expected_direct_consumption(
+        (hourly_load_wh / 4) / slot_duration_h,
+        (hourly_pv_wh / 4) / slot_duration_h,
+    )
+
+    assert quarter_hour == pytest.approx(hourly)
+
+
+def test_load_above_probability_grid_uses_highest_supported_distribution():
+    """Out-of-range household load must not make self-consumption jump to zero."""
+    interpolator = get_eos_load_interpolator()
+
+    at_boundary = interpolator.calculate_self_consumption(3450.0, 5000.0)
+    above_boundary = interpolator.calculate_self_consumption(4000.0, 5000.0)
+
+    assert above_boundary == pytest.approx(at_boundary)
+    assert above_boundary > 0.99
+
+
+def test_expected_direct_consumption_accounts_for_subhourly_load_variation():
+    """Expected overlap must be below the optimistic overlap of interval means."""
+    interpolator = get_eos_load_interpolator()
+
+    direct_power_w = interpolator.calculate_expected_direct_consumption(800.0, 1200.0)
+
+    assert direct_power_w == pytest.approx(621.0, abs=2.0)
+    assert 0.0 < direct_power_w < 800.0
+
+
+@pytest.mark.parametrize(
+    ("mean_load_power_w", "pv_power_w"),
+    [(800.0, 1200.0), (1000.0, 500.0), (1500.0, 1500.0)],
+)
+def test_expected_direct_consumption_produces_conservative_energy_balance(
+    mean_load_power_w, pv_power_w
+):
+    """Direct use, residual load and surplus must conserve both mean powers."""
+    interpolator = get_eos_load_interpolator()
+
+    direct_power_w = interpolator.calculate_expected_direct_consumption(
+        mean_load_power_w, pv_power_w
+    )
+    residual_load_w = mean_load_power_w - direct_power_w
+    pv_surplus_w = pv_power_w - direct_power_w
+
+    assert 0.0 <= direct_power_w <= min(mean_load_power_w, pv_power_w)
+    assert direct_power_w + residual_load_w == pytest.approx(mean_load_power_w)
+    assert direct_power_w + pv_surplus_w == pytest.approx(pv_power_w)
+
+
+def test_expected_direct_consumption_preserves_forecast_mean_at_high_pv():
+    """A PV level above every normalized load bin covers the complete mean load."""
+    interpolator = get_eos_load_interpolator()
+
+    direct_power_w = interpolator.calculate_expected_direct_consumption(3000.0, 10000.0)
+
+    assert direct_power_w == pytest.approx(3000.0)
diff --git a/tests/test_inverter.py b/tests/test_inverter.py
index ff82d435..2aac1dcd 100644
--- a/tests/test_inverter.py
+++ b/tests/test_inverter.py
@@ -1,8 +1,13 @@
-from unittest.mock import Mock, patch
+from unittest.mock import Mock, call, patch
 
+import numpy as np
 import pytest
 
+from akkudoktoreos.devices.genetic.battery import Battery
 from akkudoktoreos.devices.genetic.inverter import Inverter, InverterParameters
+from akkudoktoreos.devices.genetic.battery import (
+    SolarPanelBatteryParameters,
+)
 
 
 @pytest.fixture
@@ -10,6 +15,9 @@ def mock_battery() -> Mock:
     mock_battery = Mock()
     mock_battery.charge_energy = Mock(return_value=(0.0, 0.0))
     mock_battery.discharge_energy = Mock(return_value=(0.0, 0.0))
+    # Rated discharge energy of one slot - the reference a grid-export rate is
+    # applied to. Large enough to never bind at the default factor of 1.0.
+    mock_battery.rated_discharge_energy_wh = Mock(return_value=1e9)
     mock_battery.parameters.device_id = "battery1"
     return mock_battery
 
@@ -17,7 +25,7 @@ def mock_battery() -> Mock:
 @pytest.fixture
 def inverter(mock_battery) -> Inverter:
     mock_self_consumption_predictor = Mock()
-    mock_self_consumption_predictor.calculate_self_consumption.return_value = 1.0
+    mock_self_consumption_predictor.calculate_expected_direct_consumption.side_effect = min
     with patch(
         "akkudoktoreos.devices.genetic.inverter.get_eos_load_interpolator",
         return_value=mock_self_consumption_predictor,
@@ -26,11 +34,51 @@ def inverter(mock_battery) -> Inverter:
             InverterParameters(
                 device_id="iv1", max_power_wh=500.0, battery_id=mock_battery.parameters.device_id
             ),
-            battery = mock_battery
+            battery=mock_battery,
         )
         return iv
 
 
+def test_quarter_hour_load_and_grid_export_share_discharge_power_limit():
+    """Local supply plus direct export may not exceed one slot's battery budget."""
+    battery = Battery(
+        SolarPanelBatteryParameters(
+            device_id="battery",
+            capacity_wh=10000,
+            charging_efficiency=1.0,
+            discharging_efficiency=1.0,
+            max_charge_power_w=7000,
+            initial_soc_percentage=100,
+        ),
+        prediction_hours=1,
+        slot_duration_h=0.25,
+    )
+    battery.set_discharge_per_hour(np.array([1]))
+    quarter_hour_inverter = Inverter(
+        InverterParameters(
+            device_id="inverter",
+            max_power_wh=10000,
+            battery_id="battery",
+            dc_to_ac_efficiency=1.0,
+            ac_to_dc_efficiency=1.0,
+        ),
+        battery=battery,
+        slot_duration_h=0.25,
+    )
+    initial_soc_wh = battery.soc_wh
+
+    grid_export, grid_import, _, _ = quarter_hour_inverter.process_energy(
+        generation=0.0,
+        consumption=1000.0,
+        hour=0,
+        allow_battery_grid_export=True,
+    )
+
+    assert grid_import == 0.0
+    assert grid_export == pytest.approx(750.0)
+    assert initial_soc_wh - battery.soc_wh == pytest.approx(1750.0)
+
+
 def test_process_energy_excess_generation(inverter, mock_battery):
     # Battery charges 100 Wh with 10 Wh loss
     mock_battery.charge_energy.return_value = (100.0, 10.0)
@@ -48,7 +96,7 @@ def test_process_energy_excess_generation(inverter, mock_battery):
     assert self_consumption == 200.0  # All consumption is met
     mock_battery.charge_energy.assert_called_once_with(400.0, hour)
     mock_battery.discharge_energy.assert_not_called()
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
         consumption, generation
     )
 
@@ -57,7 +105,8 @@ def test_process_energy_excess_generation_interpolator(inverter, mock_battery):
     # Battery charges 100 Wh with 10 Wh loss
     mock_battery.charge_energy.return_value = (100.0, 10.0)
     mock_battery.discharge_energy.return_value = (20.0, 2.0)
-    inverter.self_consumption_predictor.calculate_self_consumption.return_value = 0.95
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.side_effect = None
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.return_value = 180.0
 
     generation = 600.0
     consumption = 200.0
@@ -67,19 +116,71 @@ def test_process_energy_excess_generation_interpolator(inverter, mock_battery):
         generation, consumption, hour
     )
 
-    assert grid_export == pytest.approx(
-        270.0, rel=1e-2
-    )  # 290 Wh feed-in - 5% of generation-consumption self consumption after battery charges
+    assert grid_export == pytest.approx(300.0, rel=1e-2)
     assert grid_import == pytest.approx(0.0, rel=1e-2)  # No grid draw
-    assert losses == 12.0  # Battery charging losses
-    assert self_consumption == 220.0  # All consumption is met
-    mock_battery.charge_energy.assert_called_once_with(pytest.approx(380.0, rel=1e-2), hour)
+    assert losses == 22.0  # Battery/inverter losses plus curtailed PV
+    assert self_consumption == 200.0  # 180 Wh direct PV + 20 Wh battery
+    mock_battery.charge_energy.assert_called_once_with(pytest.approx(420.0, rel=1e-2), hour)
     mock_battery.discharge_energy.assert_called_once_with(pytest.approx(20.0, rel=1e-2), hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
         consumption, generation
     )
 
 
+def test_probabilistic_bypass_conserves_energy_without_battery():
+    predictor = Mock()
+    predictor.calculate_expected_direct_consumption.return_value = 150.0
+    with patch(
+        "akkudoktoreos.devices.genetic.inverter.get_eos_load_interpolator",
+        return_value=predictor,
+    ):
+        inverter_without_battery = Inverter(
+            InverterParameters(device_id="inverter", max_power_wh=1000.0)
+        )
+
+    generation = 600.0
+    consumption = 200.0
+    grid_export, grid_import, losses, self_consumption = (
+        inverter_without_battery.process_energy(generation, consumption, hour=0)
+    )
+
+    assert self_consumption == pytest.approx(150.0)
+    assert grid_import == pytest.approx(50.0)
+    assert grid_export == pytest.approx(450.0)
+    assert losses == 0.0
+    assert generation + grid_import == pytest.approx(
+        consumption + grid_export + losses
+    )
+
+
+def test_probabilistic_bypass_conserves_energy_on_quarter_hour_grid():
+    predictor = Mock()
+    predictor.calculate_expected_direct_consumption.return_value = 600.0
+    with patch(
+        "akkudoktoreos.devices.genetic.inverter.get_eos_load_interpolator",
+        return_value=predictor,
+    ):
+        inverter_without_battery = Inverter(
+            InverterParameters(device_id="inverter", max_power_wh=2000.0),
+            slot_duration_h=0.25,
+        )
+
+    generation = 300.0  # 1200 W over 15 minutes
+    consumption = 200.0  # 800 W over 15 minutes
+    grid_export, grid_import, losses, self_consumption = (
+        inverter_without_battery.process_energy(generation, consumption, hour=0)
+    )
+
+    predictor.calculate_expected_direct_consumption.assert_called_once_with(800.0, 1200.0)
+    assert self_consumption == pytest.approx(150.0)
+    assert grid_import == pytest.approx(50.0)
+    assert grid_export == pytest.approx(150.0)
+    assert losses == 0.0
+    assert generation + grid_import == pytest.approx(
+        consumption + grid_export + losses
+    )
+
+
 def test_process_energy_generation_equals_consumption(inverter, mock_battery):
     generation = 300.0
     consumption = 300.0
@@ -96,7 +197,7 @@ def test_process_energy_generation_equals_consumption(inverter, mock_battery):
 
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_not_called()
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
         consumption, generation
     )
 
@@ -120,7 +221,49 @@ def test_process_energy_battery_discharges(inverter, mock_battery):
     assert self_consumption == 200.0  # Generation + battery discharge
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(150.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
+
+
+def test_process_energy_allows_battery_grid_export(inverter, mock_battery):
+    mock_battery.max_charge_power_w = 300.0
+    mock_battery.remaining_discharge_energy_wh.return_value = 200.0
+    mock_battery.discharge_energy.side_effect = [(100.0, 0.0), (200.0, 0.0)]
+
+    grid_export, grid_import, losses, self_consumption = inverter.process_energy(
+        generation=0.0,
+        consumption=100.0,
+        hour=12,
+        allow_battery_grid_export=True,
+    )
+
+    assert grid_export == pytest.approx(200.0, rel=1e-2)
+    assert grid_import == 0.0
+    assert losses == 0.0
+    assert self_consumption == 100.0
+    mock_battery.discharge_energy.assert_has_calls([call(100.0, 12), call(200.0, 12)])
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_not_called()
+
+
+def test_process_energy_grid_export_rate_limits_export(inverter, mock_battery):
+    """An export rate caps the export at that share of the rated discharge power."""
+    mock_battery.max_charge_power_w = 300.0
+    mock_battery.remaining_discharge_energy_wh.return_value = 200.0
+    mock_battery.rated_discharge_energy_wh.return_value = 300.0
+    mock_battery.discharge_energy.side_effect = [(100.0, 0.0), (150.0, 0.0)]
+
+    grid_export, grid_import, losses, self_consumption = inverter.process_energy(
+        generation=0.0,
+        consumption=100.0,
+        hour=12,
+        allow_battery_grid_export=True,
+        battery_grid_export_factor=0.5,
+    )
+
+    # 0.5 * 300 Wh rated = 150 Wh, below the 200 Wh the battery could still give.
+    assert grid_export == pytest.approx(150.0)
+    mock_battery.discharge_energy.assert_has_calls([call(100.0, 12), call(150.0, 12)])
 
 
 def test_process_energy_battery_empty(inverter, mock_battery):
@@ -140,7 +283,9 @@ def test_process_energy_battery_empty(inverter, mock_battery):
     assert self_consumption == 100.0  # Only generation is consumed
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(200.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
 
 
 def test_process_energy_battery_full_at_start(inverter, mock_battery):
@@ -162,7 +307,7 @@ def test_process_energy_battery_full_at_start(inverter, mock_battery):
     assert self_consumption == 200.0  # Only consumption is met
     mock_battery.charge_energy.assert_called_once_with(300.0, hour)
     mock_battery.discharge_energy.assert_not_called()
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
         consumption, generation
     )
 
@@ -184,7 +329,9 @@ def test_process_energy_insufficient_generation_no_battery(inverter, mock_batter
     assert self_consumption == 100.0  # Only generation is consumed
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(400.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
 
 
 def test_process_energy_insufficient_generation_battery_assists(inverter, mock_battery):
@@ -209,7 +356,9 @@ def test_process_energy_insufficient_generation_battery_assists(inverter, mock_b
     assert self_consumption == 250.0  # Generation + battery discharge
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(200.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
 
 
 def test_process_energy_zero_generation(inverter, mock_battery):
@@ -232,7 +381,7 @@ def test_process_energy_zero_generation(inverter, mock_battery):
     assert self_consumption == 100.0  # Only battery discharge is consumed
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(300.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_not_called()
 
 
 def test_process_energy_zero_consumption(inverter, mock_battery):
@@ -252,9 +401,7 @@ def test_process_energy_zero_consumption(inverter, mock_battery):
     assert self_consumption == 0.0  # Zero consumption
     mock_battery.charge_energy.assert_called_once_with(500.0, hour)
     mock_battery.discharge_energy.assert_not_called()
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
-        consumption, generation
-    )
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_not_called()
 
 
 def test_process_energy_zero_generation_zero_consumption(inverter, mock_battery):
@@ -272,9 +419,7 @@ def test_process_energy_zero_generation_zero_consumption(inverter, mock_battery)
     assert self_consumption == 0.0  # No consumption
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_not_called()
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_called_once_with(
-        consumption, generation
-    )
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_not_called()
 
 
 def test_process_energy_partial_battery_discharge(inverter, mock_battery):
@@ -295,7 +440,9 @@ def test_process_energy_partial_battery_discharge(inverter, mock_battery):
     assert self_consumption == 250.0  # Generation + battery discharge
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(200.0, 12)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
 
 
 def test_process_energy_consumption_exceeds_max_no_battery(inverter, mock_battery):
@@ -315,7 +462,9 @@ def test_process_energy_consumption_exceeds_max_no_battery(inverter, mock_batter
     assert self_consumption == 100.0  # Only the generation is consumed, maxing out the inverter
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(400.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_called_once_with(
+        consumption, generation
+    )
 
 
 def test_process_energy_zero_generation_full_battery_high_consumption(inverter, mock_battery):
@@ -337,4 +486,4 @@ def test_process_energy_zero_generation_full_battery_high_consumption(inverter,
     assert self_consumption == 500.0  # Battery fully discharges to meet consumption
     mock_battery.charge_energy.assert_not_called()
     mock_battery.discharge_energy.assert_called_once_with(500.0, hour)
-    inverter.self_consumption_predictor.calculate_self_consumption.assert_not_called()
+    inverter.self_consumption_predictor.calculate_expected_direct_consumption.assert_not_called()
diff --git a/tests/test_inverter_efficiency.py b/tests/test_inverter_efficiency.py
index f3f24f8b..aeb438b1 100644
--- a/tests/test_inverter_efficiency.py
+++ b/tests/test_inverter_efficiency.py
@@ -17,14 +17,11 @@ from unittest.mock import Mock, patch
 import numpy as np
 import pytest
 
+from akkudoktoreos.devices.genetic.battery import Battery
+from akkudoktoreos.devices.genetic.inverter import Inverter, InverterParameters
 from akkudoktoreos.devices.genetic.battery import (
-    Battery,
     SolarPanelBatteryParameters,
 )
-from akkudoktoreos.devices.genetic.inverter import (
-    Inverter,
-    InverterParameters,
-)
 
 # ---------------------------------------------------------------------------
 # Helpers / Fixtures
@@ -40,7 +37,7 @@ def _make_inverter(
 ) -> Inverter:
     """Create an Inverter with custom efficiency parameters and a mock battery."""
     mock_self_consumption_predictor = Mock()
-    mock_self_consumption_predictor.calculate_self_consumption.return_value = 1.0
+    mock_self_consumption_predictor.calculate_expected_direct_consumption.side_effect = min
 
     params = InverterParameters(
         device_id="inv1",
@@ -167,12 +164,14 @@ class TestDcToAcEfficiency:
         assert losses == pytest.approx(10.0, rel=1e-5)  # Only battery losses
 
     def test_discharge_surplus_path_with_efficiency(self, mock_battery):
-        """When generation > consumption but SCR < 1, discharge goes through inverter."""
-        mock_battery.discharge_energy.return_value = (50.0, 5.0)
+        """A probabilistic load gap discharges through the inverter."""
+        mock_battery.discharge_energy.return_value = (30.0 / 0.90, 5.0)
         mock_battery.charge_energy.return_value = (100.0, 10.0)
 
         inv = _make_inverter(dc_to_ac_efficiency=0.90, mock_battery=mock_battery)
-        cast(Mock, inv.self_consumption_predictor).calculate_self_consumption.return_value = 0.90
+        predictor = cast(Mock, inv.self_consumption_predictor)
+        predictor.calculate_expected_direct_consumption.side_effect = None
+        predictor.calculate_expected_direct_consumption.return_value = 170.0
 
         generation = 500.0
         consumption = 200.0
@@ -182,18 +181,23 @@ class TestDcToAcEfficiency:
             generation, consumption, hour
         )
 
-        # surplus = 300, remaining_power = 300*0.9 = 270, remaining_load_evq = 300*0.1 = 30
-        # DC request for discharge = 30 / 0.90 = 33.333
+        # Expected direct PV is 170 Wh, leaving 30 Wh of load gap and
+        # 330 Wh of PV surplus within different sub-periods of the slot.
+        # DC request for discharge = 30 / 0.90 = 33.333 Wh.
         expected_dc_request = 30.0 / 0.90
         mock_battery.discharge_energy.assert_called_once_with(
             pytest.approx(expected_dc_request, rel=1e-3), hour
         )
 
-        # Battery delivers 50 Wh DC → 45 Wh AC
-        from_battery_ac = 50.0 * 0.90  # 45 Wh
-        inverter_discharge_loss = 50.0 - from_battery_ac  # 5 Wh
+        # Battery delivers 33.333 Wh DC -> 30 Wh AC.
+        from_battery_dc = 30.0 / 0.90
+        from_battery_ac = from_battery_dc * 0.90
+        inverter_discharge_loss = from_battery_dc - from_battery_ac
 
-        assert self_consumption == pytest.approx(consumption + from_battery_ac, rel=1e-5)
+        assert self_consumption == pytest.approx(170.0 + from_battery_ac, rel=1e-5)
+        assert grid_import == pytest.approx(0.0)
+        assert grid_export == pytest.approx(220.0)
+        assert losses == pytest.approx(5.0 + inverter_discharge_loss + 10.0)
 
 
 # ===================================================================