diff --git a/pvsim/panel.py b/pvsim/panel.py
new file mode 100644
index 0000000..bbf611d
--- /dev/null
+++ b/pvsim/panel.py
@@ -0,0 +1,243 @@
+```python
+"""
+panel.py
+
+Modello del singolo pannello fotovoltaico.
+
+Ogni pannello riceve dal simulatore:
+
+- Irradianza [W/m²]
+- Temperatura ambiente [°C]
+- Timestamp
+
+e restituisce le principali grandezze elettriche.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from datetime import datetime
+from typing import Dict
+import random
+import math
+
+
+@dataclass
+class PVPanel:
+
+    panel_id: str
+
+    nominal_power: float = 450.0          # W
+    area: float = 2.1                     # m²
+
+    vmp: float = 41.5
+    imp: float = 10.85
+
+    voc: float = 49.8
+    isc: float = 11.35
+
+    temp_coeff: float = -0.0035           # -0.35 %/°C
+
+    nominal_temp: float = 25.0
+
+    annual_degradation: float = 0.005
+
+    sensor_noise: float = 0.01
+
+    # stato pannello
+    enabled: bool = True
+    soiling_factor: float = 1.0
+    degradation: float = 1.0
+
+    total_energy_Wh: float = 0.0
+
+    # ------------------------------------------------------------------
+
+    def module_temperature(
+        self,
+        ambient_temperature: float,
+        irradiance: float
+    ) -> float:
+        """
+        Stima della temperatura del modulo.
+
+        Formula semplificata:
+        Tmodule = Tamb + irradiance * 0.03
+        """
+
+        return ambient_temperature + irradiance * 0.03
+
+    # ------------------------------------------------------------------
+
+    def degradation_factor(
+        self,
+        years: float
+    ) -> float:
+
+        return (1.0 - self.annual_degradation) ** years
+
+    # ------------------------------------------------------------------
+
+    def compute_power(
+        self,
+        irradiance: float,
+        ambient_temperature: float,
+        years_from_start: float
+    ) -> float:
+
+        if not self.enabled:
+            return 0.0
+
+        module_temp = self.module_temperature(
+            ambient_temperature,
+            irradiance
+        )
+
+        temp_factor = (
+            1 +
+            self.temp_coeff *
+            (module_temp - self.nominal_temp)
+        )
+
+        degr = self.degradation_factor(years_from_start)
+
+        power = (
+            self.nominal_power *
+            (irradiance / 1000.0) *
+            temp_factor *
+            degr *
+            self.soiling_factor
+        )
+
+        power = max(power, 0.0)
+
+        noise = random.gauss(1.0, self.sensor_noise)
+
+        return power * noise
+
+    # ------------------------------------------------------------------
+
+    def compute_voltage(
+        self,
+        power: float
+    ) -> float:
+
+        if power <= 0:
+            return 0.0
+
+        voltage = self.vmp * (
+            0.98 + 0.04 * random.random()
+        )
+
+        return voltage
+
+    # ------------------------------------------------------------------
+
+    def compute_current(
+        self,
+        power: float,
+        voltage: float
+    ) -> float:
+
+        if voltage <= 0:
+            return 0.0
+
+        return power / voltage
+
+    # ------------------------------------------------------------------
+
+    def update(
+        self,
+        timestamp: datetime,
+        irradiance: float,
+        ambient_temperature: float,
+        years_from_start: float,
+        timestep_minutes: float
+    ) -> Dict:
+
+        power = self.compute_power(
+            irradiance,
+            ambient_temperature,
+            years_from_start
+        )
+
+        voltage = self.compute_voltage(power)
+
+        current = self.compute_current(
+            power,
+            voltage
+        )
+
+        module_temp = self.module_temperature(
+            ambient_temperature,
+            irradiance
+        )
+
+        energy = power * timestep_minutes / 60.0
+
+        self.total_energy_Wh += energy
+
+        return {
+
+            "timestamp": timestamp,
+
+            "panel_id": self.panel_id,
+
+            "irradiance_Wm2": irradiance,
+
+            "ambient_temperature_C": ambient_temperature,
+
+            "module_temperature_C": module_temp,
+
+            "voltage_V": voltage,
+
+            "current_A": current,
+
+            "power_W": power,
+
+            "energy_Wh": energy,
+
+            "total_energy_Wh": self.total_energy_Wh,
+
+            "enabled": self.enabled,
+
+            "soiling_factor": self.soiling_factor,
+
+            "degradation_factor":
+                self.degradation_factor(years_from_start)
+
+        }
+
+    # ------------------------------------------------------------------
+
+    def fail(self):
+
+        self.enabled = False
+
+    # ------------------------------------------------------------------
+
+    def repair(self):
+
+        self.enabled = True
+
+    # ------------------------------------------------------------------
+
+    def soil(self, loss=0.9):
+
+        self.soiling_factor = loss
+
+    # ------------------------------------------------------------------
+
+    def clean(self):
+
+        self.soiling_factor = 1.0
+
+    # ------------------------------------------------------------------
+
+    def __repr__(self):
+
+        return (
+            f"PVPanel("
+            f"{self.panel_id}, "
+            f"{self.nominal_power}W)"
+        )
\ No newline at end of file