Optimization of the Inverter class to speed up scr calculation (#607)

* fix(ElecPriceEnergyCharts): get history series, update docs

Signed-off-by: redmoon2711 <redmoon2711@gmx.de>

* feat(inverter): using lookup table for calculate scr

Signed-off-by: redmoon2711 <redmoon2711@gmx.de>

---------

Signed-off-by: redmoon2711 <redmoon2711@gmx.de>

Author: redmoon2711

src/akkudoktoreos/devices/inverter.py

@@ -25,6 +25,22 @@ def __init__(
         self.parameters: Optional[InverterParameters] = None
         super().__init__(parameters)
 
+        self.scr_lookup: dict = {}
+
+    def _calculate_scr(self, consumption: float, generation: float) -> float:
+        """Check if the consumption and production is in the lookup table. If not, calculate and store the value."""
+        if consumption not in self.scr_lookup:
+            self.scr_lookup[consumption] = {}
+
+        if generation not in self.scr_lookup[consumption]:
+            scr = self.self_consumption_predictor.calculate_self_consumption(
+                consumption, generation
+            )
+            self.scr_lookup[consumption][generation] = scr
+            return scr
+
+        return self.scr_lookup[consumption][generation]
+
     def _setup(self) -> None:
         if self.parameters is None:
             raise ValueError(f"Parameters not set: {self.parameters}")
@@ -60,9 +76,8 @@ def process_energy(
                 grid_import = -remaining_power  # Negative indicates feeding into the grid
                 self_consumption = self.max_power_wh
             else:
-                scr = self.self_consumption_predictor.calculate_self_consumption(
-                    consumption, generation
-                )
+                # Calculate scr with lookup table
+                scr = self._calculate_scr(consumption, generation)
 
                 # Remaining power after consumption
                 remaining_power = (generation - consumption) * scr  # EVQ