diff --git a/Utilities/Shading.py b/Utilities/Shading.py
index ce3480e..58f99cd 100644
--- a/Utilities/Shading.py
+++ b/Utilities/Shading.py
@@ -151,8 +151,8 @@ def calculate_energy_production_vertical(c):
     axis_azimuth = 90
 
     morning_shaded_fraction = pvlib.shading.shaded_fraction1d(
-        solar_zenith=morning_solar_positions["zenith"],
-        solar_azimuth=morning_solar_positions["azimuth"],
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
         axis_azimuth=axis_azimuth,
         shaded_row_rotation=shaded_row_rotation,
         shading_row_rotation=shading_row_rotation,
@@ -164,8 +164,8 @@ def calculate_energy_production_vertical(c):
     morning_shaded_fraction = morning_shaded_fraction * no_of_shaded_rows / no_of_rows
 
     afternoon_shaded_fraction = pvlib.shading.shaded_fraction1d(
-        solar_zenith=afternoon_solar_positions["zenith"],
-        solar_azimuth=afternoon_solar_positions["azimuth"],
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
         axis_azimuth=axis_azimuth + 180,
         shaded_row_rotation=shaded_row_rotation,
         shading_row_rotation=shading_row_rotation,
@@ -185,12 +185,12 @@ def calculate_energy_production_vertical(c):
     poa_front = pvlib.irradiance.get_total_irradiance(
         surface_tilt=90,
         surface_azimuth=axis_azimuth,
-        solar_zenith=morning_solar_positions["zenith"],
-        solar_azimuth=morning_solar_positions["azimuth"],
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
         dni=clearsky_data["dni"],
         ghi=clearsky_data["ghi"],
         dhi=clearsky_data["dhi"],
-        albedo=0.5,
+        surface_type="urban",
     )
     # drop rows with poa_global NaN values
     poa_front = poa_front.dropna(subset=["poa_global"])
@@ -198,12 +198,12 @@ def calculate_energy_production_vertical(c):
     poa_rear = pvlib.irradiance.get_total_irradiance(
         surface_tilt=180 - 90,
         surface_azimuth=axis_azimuth + 180,
-        solar_zenith=afternoon_solar_positions["zenith"],
-        solar_azimuth=afternoon_solar_positions["azimuth"],
+        solar_zenith=solar_positions["zenith"],
+        solar_azimuth=solar_positions["azimuth"],
         dni=clearsky_data["dni"],
         ghi=clearsky_data["ghi"],
         dhi=clearsky_data["dhi"],
-        albedo=0.5,
+        surface_type="urban",
     )
     # drop rows with poa_global NaN values
     poa_rear = poa_rear.dropna(subset=["poa_global"])
@@ -222,7 +222,7 @@ def calculate_energy_production_vertical(c):
 
     energy_front = effective_front * 15 / 60 / 1e3
     energy_rear = effective_rear * 15 / 60 / 1e3
-    total_hourly_energy_m2 = energy_front.add(energy_rear, fill_value=0)
+    total_hourly_energy_m2 = energy_front + energy_rear
     energy_total = total_hourly_energy_m2.sum()
     logger.info(f"Energy yield calculated: {energy_total} kWh/m2")
 
diff --git a/main.py b/main.py
index e399ed0..ec7b992 100644
--- a/main.py
+++ b/main.py
@@ -30,13 +30,14 @@ logger.info("Configuration loaded successfully.")
 logger.debug(f"Configuration: {c}")
 
 # calculate energy production for horizontal and vertical panels
+vertical_energy = calculate_energy_production_vertical(c)
+logger.info("Energy production for vertical panels calculated successfully.")
+logger.debug(f"Vertical Energy Production: {vertical_energy.sum()}")
+
 horizontal_energy = calculate_energy_production_horizontal(c)
 logger.info("Energy production for horizontal panels calculated successfully.")
 logger.debug(f"Horizontal Energy Production: {horizontal_energy.sum()}")
 
-vertical_energy = calculate_energy_production_vertical(c)
-logger.info("Energy production for vertical panels calculated successfully.")
-logger.debug(f"Vertical Energy Production: {vertical_energy.sum()}")
 
 NOVA_scaledown = 0.75